Transcript:
there we are
um
um
for all of you that may be listening in the audience or you know those of you that
are speakers that belong to groups in astronomy you might want to share this program this
is an educational outreach program by the astronomical league
the way we do outreach is by sharing
hmm
hmm um
hmm
so
Dark Matter
we all know what a galaxy looks like right it's a huge collection of stars and other matter that's shaped like a
spiral or an ellipse and if you're an astronomy fan you probably know that most of the mass is from invisible
mysterious material called dark matter well nasa's hubble space telescope just
took an image of a galaxy that is none of those things for the first time astronomers have strong evidence for a
galaxy not having a significant amount of dark matter most astronomers currently believe that dark
matter plays a fundamental role in our universe and the formation of galaxies this is because galaxies seem to have a
lot more mass than what we can account for based on just the stars we see how much mass is in a system is
determined by measuring the speed at which galaxies rotate or individual stars in a galaxy move
without the gravity from that mass a galaxy would fly apart if everything in it is moving as quickly as we observe it
moving decades of research have led astronomers to the extraordinary conclusion
that 85 of the mass in our universe is invisible in all wavelengths of radiation and that
it's composed of matter that does not contain protons or neutrons or any type of particle we detected
before and that this invisible material is all around us passing through us without interacting
with regular matter except by gravity for some that's a tough pill to swallow
and a minority of astronomers wonder maybe we just don't completely understand how gravity works
if that were the case and it was an inherent property of gravity that causes galaxies to move the way they do
then we can expect all galaxies to behave the same way in other words they would all seem to have about the same portion
of dark matter but with the galaxy in this hubble image astronomers looked at the velocities of
10 globular clusters in the galaxy each a spherical collection of hundreds of thousands of stars
and calculated that their movements can be accounted for entirely by the mass of the visible material in this system
that means this galaxy has little to no dark matter strangely this absence of dark matter
actually provides evidence that dark matter is real it shows that dark matter isn't always coupled with regular matter that is
something separate you can have regular matter without dark matter this galaxy is really weird even beyond
the dark matter thing you may have noticed you can see straight through it that's because this galaxy is what's called
an ultra diffuse galaxy which as the name implies is extremely low density
this galaxy is about the same volume as our own milky way galaxy but only has about 0.5 percent the
amount of stars though astronomers have known about ultra diffuse galaxies since the early 1980s
they can be difficult to find since they're so faint a team of astronomers is using an array of telephoto lenses
called dragonfly to seek out these ghostly looking objects they obtained observations from
dragonfly the sloan digital sky survey the gemini observatory and the keck observatory
then requested time on the hubble space telescope to take a closer look at this unusual galaxy
having images and data from multiple sources allows the team to determine that this galaxy does not have
a significant amount of dark matter this was definitely surprising to find no other galaxies so far have appeared
to be so lacking in dark matter in fact other ultra diffuse galaxies seem to have an over
abundance of dark matter the same team who studied this galaxy discovered a different ultra diffuse galaxy in 2016
that they calculated was 99.9 dark matter yet another weird thing
about this galaxy the globular cluster is used to measure the galaxy's rotation are way brighter than normal globular
clusters the researchers have written a different paper that focuses on just these oddball collections of stars
so this is a very strange galaxy in several ways astronomers will be looking at hubble
observations of other ultra-diffuse galaxies to see if there are any other examples of galaxies with unusually low or high
amounts of dark matter with more samples astronomers will be able to better understand the nature of dark matter
the formation and evolution of galaxies and the overall structure of our
Welcome
universe
well hello everyone this is scott roberts here and we're introducing the astronomical
league live number three and this is with keynote speaker rachel cianetti and it's my pleasure to
introduce the other people here just to get started we have president carol org uh
with us we have don nab who will be speaking terry mann who is a
former two-term uh president of the astronomical league and secretary of the league now
dr david levy who will be opening our program today of course rachel as well and
giving the keynote chuck allen former president of the astronomical league and john goss
who i think also is a former president in fact i know he's the former former president of the astronomical
league so we're all here during this uh chilly winter winter night here it
might be warm where you are but it's cold here so i'm glad to be here with warm friends
and uh and here with another exciting uh program with the astronomical league
um uh terry i am going to turn this program over to you uh and uh this is going to be exciting
thank you very much scott it is so nice to be able to see everybody again it's it's so great doing zoom
Introductions
because at least if i can't see you in person i'm seeing a lot of you probably more
than i would if we were doing this in person so it's really been nice uh thank you all for being here and
thank you for everybody that is watching we really appreciate it so it's my pleasure to introduce david
levy now david and i go back a few years too and his wife wendy i have been at their house and they are
just amazingly friendly people i had such a great time there
and david and i ran into each other too at some different conferences we sat on the same board at one time
um so our history kind of goes way back too and i've always enjoyed everything that
he has said and loved his books so david thank you for being here and i am going to turn it over to you
thank you thanks terry and thanks scotty and i'm really very happy to be here
tonight to help introduce our speaker rachel tonight who's going to give an excellent
lecture i am supposed to give a quote from shakespeare
at the beginning of every one of these events so i looked through every word of william
shakespeare until i found something about rachel and here it is rachel will
be lecturing hereafter tonight there will be a time for such a word
tonight and tonight and tonight creeps in its roaring pace from night to night
to all the syllables of recorded time and will continue to be heard after that
light light brief candle life's but a racing football player a
rich player that shines his hour upon the stage and then
is heard forever more it is a tale told by a genius full of
sound and fury signifying everything now of course this is obviously not by shake spirits
a little bit by shakespeare and a few little things changed to make rachel feel a little
better but i actually did find something by shakespeare that that actually does deal a little bit
with dark matter and energy but not in the sense that we would see it in the 21st century
it is an attempt by shakespeare to actually talk about an eclipse of the sun where darkness appears
he does not mention the word eclipse he does not mention the word darkness
and wendy and i found out about this particular quote when we were on a cruise and somebody
actually mentioned it it's one of my turns out to be one of my favorite quotations
and this is also from macbeth he talks about an eclipse of the sun this way by the clock tis day
and yet dark night strangles the traveling lamp is it the night's predominance or the
day's shame that darkness says the face of earth and tomb when living light should kiss it thank you
and back to you terry thank you david that was very nice
appreciate that i'd like to go ahead and move on to
chuck allen and he as he was just introduced chuck is a past president of the astronomical league and he is the
current vice president of the astronomical league and he is here to speak
about the awards so chuck i'm going to turn that over to you thanks terry and good evening everyone
League Awards
um i'd like to go straight to a slide set if i may um if i can share a
screen here and we'll go here
and the current slide and what you see here is why i'm speaking with you tonight it
is league awards season and this is very important whether you're a member of the astronomical league or not
so you might want to pay attention here and if you are in an astronomical league club this may
apply to some of your members as well uh let me start with our youth awards
the youth awards that we have start with the national young astronomer award which spotlights research done by young
people of high school age for this award you need to be a united states citizen or
enrolled in a u.s high school between 14 and 19 years of age at the time of
nomination and not enrolled in college if you're taking an isolated course in college that's okay
just let us know and we'll make a determination on that uh this award is uh sponsored here's our
current winner from 2020 karen lee who did an incredible amount of research
actually determining for the first time the source of neutral 21 centimeter hydrogen source in the sky
something that even professionals have not done hitherto
this award is sponsored by our host tonight of course scott roberts of science of
explore scientific he provides wonderful telescope prizes to our winner
our winner is brought to the national convention each year and receives a great plaque
so we would encourage you to add this to your resume before you apply to college
we also have youth service awards that are sponsored by the horkheimer charitable fund uh we have the horkheimer smith and
daria awards they're really two awards that are given if you apply for the service awards
and these awards provide large cash prizes and the winner of the smith award is
also given a trip to our national convention to receive the awards
in addition we have the horkheimer parker youth imaging award which goes to young people who engage in
imaging again this is for under 19s you see we have large cash browsers for
this as well and we have a journalism award for uh
you know league members who are eight to 14 years of age it requires the writing of an essay not to exceed 500 words
on a scientific topic does not necessarily have to be an astronomy topic so we would encourage club officers
any club member if you have young people in your club who have engaged in service or engaged in imaging
or are interested in writing please have them enter these award programs the deadlines are
all march 31st we also have national awards uh the
start of that of course is our highest award which is the astronomical league award here being received by
richard gott of princeton in 1998 we have in addition to that the
mabel stearns newsletter editor award uh submissions for that are due by march 31st we have a webmaster award
so if your club newsletter editor or your webmaster does exceptional work please consider nominating them for this
award we also have a leslie peltier award which goes to people who engage in
extraordinary observing efforts and achievements
and nominations can be made for this as well to the committee jim fox here
is a winner for example of our 2014 peltier award for doing uh photometric research on the
atmospheres of uranus and neptune we also have a sketching award which provides
cash prizes to its winner sponsored by astronomics
and soon we will be announcing uh an explore scientific sponsored imaging award
we haven't worked out the details of this yet and the deadline will probably be later than march 31st and so watch the website for that
and we'll be making announcements in future live events about this we also have a new award for imaging
that is open to female league members aged 19 and over right now we're working on
sponsorship of this award the deadline will be later it'll be may 31st because we need to announce this in the
reflector in march we also have the horkheimer library telescope
program the league gives out to one club in each of our 10 regions
a library telescope for them to place in a library near them
clubs must enter this before the march 31st deadline and this too is sponsored by the horkheimer
charitable fund and this is a very popular program uh linking you with libraries in your area
applying is easy i will caution you that our website is undergoing a major transformation right now uh we're moving
from one platform to another so some of our pages are a little out of date but they still work
so go to our website at www.astralig.org and look for awards on the menu
on the left side and when you get there you'll find a number of links in yellow along the left side of the
column here and choose the one you're interested in national young astronomer award jack
horkheimer's service awards should actually read youth awards because this link goes to all of the horkheimer
awards mabel stearns here and so forth once you click on let's say the horkheimer awards
you will find a mention of our service awards our imaging awards and our journalism awards
and direct links to pages that will take you to application forms these forms may read 2020 don't
worry about it just submit it some of them have instruction sheets to make it clear what we need from you
in applying for these awards so here's the summary uh of what we have we have the four major
youth awards actually it's five because the service award is double as
you see you do not need to be a league member to apply for the national young astronomer award you
do need to be a league member within certain age parameters for the other poor comer awards
our astronomical league award is open to anyone the webmaster and mabel stern sketching
fleming and explorer scientific imaging awards will be open to league members and the fleming award has some
additional requirements again please nominate someone or apply
yourself for these awards all of the deadlines are march 31st of this year except for wilhelmina fleming
which is may 31st and the imaging award which will be announced shortly if you have any questions or can't find
a form that works or have any trouble at all contact me my email address appears at the bottom
simply vice president astrology.org and i'll take care of any questions you
have or allow you simply to submit to me and i'll make sure it's considered so that's uh that's the awards program
Door Prizes
that we're working on right now and i hope you will take some time to consider whether some of your members or perhaps
yourself is deserving of recognition by the astronomical league this year thank you very much terry thank you
chuck i appreciate that um yes just please bear with us as we are working on the website changing
platforms uh chuck is very quick on email if there's any problems definitely drop him an email
and now what i would like to do as you know a lot we give away door prizes and on this
event we will be giving away three oh that doesn't work very well does it three calendars let me find the right
spot here disappearing three astronomical league calendars
and they are really fantastic i i have really enjoyed it there is something almost on every day
in this cat there really is in this calendar uh and the images
uh it is they're really nice very nice and the proceeds will go to the youth
program to alcon jr so we really appreciate your support there and so we will be giving away
three of these one two three of winners and what you are going to do is send
your answers to secretary at astroleague.org and you're going to see this on the
bottom of i'm going to share my screen
on the bottom of each slide here and so i'm going to ask these questions
as soon as this goes but what i would like to start with is
as we do on every slide program that we do for these questions we want to warn you about ever looking
at the sun without the proper filters you do not want to do that anytime you look at the sun make sure
you have the proper filters on your telescope or your binoculars i've had people come
up and ask me if just looking at through sunglasses wasn't fine or if i put on two pairs
isn't that good and no no we definitely don't want anything to happen to anybody's vision
always make sure when you look at the sun you you use a certified solar filter
and anytime you have any questions about that contact somebody before you ever look at the sun
without filters never do that and this is the calendar as i was trying to show you this is much better
uh gives you an idea of what it looks like and every day in there has a bit of either league history or what's going on
in the sky uh information about the other picture that is also with that calendar page
they're fantastic calendars now first question let's say you're
going to participate in a messier marathon and it's going to be in march and it's going to be in the mid northern
latitude what object will be your challenge object it will be the last object you view in
the morning and send your answers as i said over here to the side to secretary at
astroleague.org and i will be giving the answers after rachel's talk
and so the winners will be announced before the end of this program and so put your answers in as soon as
you can second question the flooded floor of cassini craters
shows many impacts which is the largest crater that sits entirely within the rim
and the last question this looks like big bird to me in the middle hubble took this
image what object is this and send your answers in as soon as you
can secretary at astroleague.org
terry yes may i interrupt just a moment uh something came to my attention about
the solar warnings that we give and since we may have young people watching this tonight i'd like to add something just
as caution you may go to events that are sponsored by local astronomy societies where
telescopes with very sophisticated white light and h alpha filters are being used and you can safely observe the sun
through these instruments do not think though that that means you can look through any telescope at the sun
those are special telescopes and most telescopes don't have that equipment on them so
make sure when you're talking about solar observing that you're with someone who knows what they're doing they're using professional equipment
and let me add also if you're not in a league club and you're interested in some of these youth awards
you can join the league for twenty dollars if you're under nineteen uh we have membership at large for that
thank you terry and i'm sorry to interrupt you no problem chuck but that brings up another quote or another
thing too sky puppies maybe we should talk a little bit about sky puppies could you
do talk a little bit about that yes uh we have a number of observing
programs in fact the astronomical league has the most robust series of observing programs of any organization in the
world we have more than 80 of them these programs require people to observe a certain list of objects sometimes to
sketch them some and always to describe them and to log information about the observation
site transparency seeing in other conditions
for example one program would have you observe 110 planetary nebulae or 100 globular clusters or the entire
messier catalog as examples of three of them but we also have beginner programs
programs that are highly suited for people just getting started in astronomy these programs teach you fundamentals
about star hopping to targets using charts understanding right ascension and declination in the sky
recognizing key asterisms that are visible to the unaided eye or to binoculars
and these are important sky puppies is one of these beyond polaris is one of these programs
the basic messier program is not difficult for example and we have an urban sky
program if you have to observe from your backyard in a light polluted area you can do that
program or one of our lunar programs and these are really exciting programs
to pursue and you get a great sense of achievement from doing them so i would encourage you to go to our website
and go to the observing programs page and find yourself a program that is suitable for that
i do have a slide that summarizes some of the basic programs but i don't have quick access to terry but i'll be happy to bring that up
later if you'd like sure and skype puppies if i'm not mistaken correct me if i'm wrong
this can be a free program for kids under 10. that's ground yeah they do not have to
be league members it could be anybody a child under 10. that's correct that's something to
consider especially if you're a teacher out there and need any information about sky puppies please get on our website
astroleague.org and check that out and i think it's aaron that uh is over
that yes i think yeah okay and so aaron will get back to you but that i think that's a great benefit to have for any
child that's just getting started in astronomy and it will help the parents learn too if they don't know much about astronomy
so i think that's a an amazing deal there so thank you chuck i really appreciate that
um and right now john goss you're going to be up john as we said is a past president of
the league always involved in a lot of things he's media director right now
and he is yeah wearing all kinds of hats and he is also chairing our 75th
anniversary which will be in november so john um give us your talk
and let's see what's going on all right thank you terry um actually this is a real pleasure to
League History
be speaking with everybody tonight because we are celebrating our 75th year as an
organization it all began in [Music] november 15 1946 so we aren't quite 75
years yet but we only had back then we only had about 67 dollars in the bank account
and about 1500 members today i can't tell you how much we have in the bank account but a lot more than 67
dollars uh and we have a lot more than fifteen hundred members right now we're up to about eighteen thousand
i don't think we've broken nineteen thousand yet but uh over the past few years our membership has been going up
up up and up so it's been really really good for the league and really good for amateur astronomy
um you know the more members we have uh the more we can do for amateur astronomy
as as a whole and our membership in in in particular uh since the 1940s
um you can imagine all the changes that have come about in the science as well as in the hobby there have been
a lot of changes but in our hearts though i think we're the same type of people
as we were back then you know back then we we liked observing we like being out
under the stars we like seeing cool stuff we like sharing the uh the the sights in the night sky with
others and we've always liked our really cool equipment you know as you can imagine this hobby has
the coolest equipment around back in the 40s 50s and 60s a lot of this stuff was homemade
and and same same today but we've had a lot of manufacturers come on the scene uh providing us with
quality equipment the price has always been been dropping really so it's
the the hobby has never been more accessible now than it has ever been i mean anyone can can jump in the hobby and
really enjoy it um you know with the league though we started out small we started out
with not very many uh benefits really the first things that the league officers did was to talk with clubs
around the country and find out what they wanted find out what they thought a new national organization could provide
one of the things that they came up with was the reflector magazine back then it was called the bulletin and
i'll show you some of that in just a few minutes um today though we now have the reflector magazine which is a pretty
sophisticated publication i may say um we started having observing clubs
back in the late 1960s and as uh chuck was just saying i think he said over 80 today
and that that's incredible uh um i can't talk about it because there
that's an hour-long conversation here to talk about the clubs in in uh particular but anyway uh so we've
grown quite a bit in that the awards with shark candles has grown quite a bit too our first uh word structure for youth
was the uh national young astronomer started in 1993 i think that's the correct year
and we've gone on from there so today we have 10 pathways for a young person to receive an award
we have a book service which helps um defray the cost of ordering books now
we have a library telescope program which chuck has has talked about we have about a bunch
of benefits and it's start thinking about the league and what it is and what it can do you know just think about the annual meetings that the league is involved
with we have our national convention al khan but we also have uh more regional conventions and even smaller
smaller gatherings than that star parties and so on the winter star party is going on right now in florida
uh and if you've been following that on the on the league facebook page it's been pretty interesting seeing some of the stuff that goes on there
so just think of all the stuff that leak does today to help help amateur astronomy now i i have a a slide set which i'd
like to show terry show not just terry but everybody sorry
my syntax there was kind of off
League 75th Anniversary
okay let me uh so here i am talking about the 75th
anniversary um one person i'd like to point out before i go any further is
when i our members peggy walker who's put together a lot of the events and uh did a lot of the leg work
uh trying to track down stuff that we could do and her help has been very very much appreciated
okay this is uh a photocopy of the astronomically bulletin the very first
publication of the astronomical league which was in according to this september of 1949.
so this is just a front and back side and today we're with a full color glossy magazine
that's about 32 pages and written by uh articles written by amateur astronomers
foreign astronomers so it's um it's really interesting and it's it's
it gives a lot of good news about the hobby around the country we have all these many observing clubs
and with those you normally get a nice lapel pin and a certificate suitable for framing
uh to announce your accomplishment we also have some um other items we we
do for complete completely free we have a system called outreach downloads which gives a number
of flyers that you can hand out that helps explain our our hobby helps answer questions
that a lot of people have helps you find your way around the nice sky such as this one
navigating the mid to late march night sky which is what's coming up next month on uh this is free and it's on our
facebook page it will be regularly scheduled on our website when the uh revamp is completed with that so keep
keep your eyes peeled for this stuff library telescope program as as as chuck
was saying we give away up up to 11 telescopes per year we've been doing this since
since 2015. so there's quite a few telescopes out there now out to different clubs who uh applied
for this encouraging for that we as i said we're on our 75th anniversary
we have a nice lapel pin designed uh we have uh in our top secret labs
they are cobbling this together cranking out them by the thousands so and hopefully in the next uh couple
months we'll have these available for sale through lake sales one oh one more thing is
league sales i forgot about that good because i'm wearing a league sales product right here
uh the old knit hat with the astronomical league i've tried this out personally it keeps my head very warm when i'm out
under the stars so if you want something really cool to wear and to show your astronomical awareness get one of these
hats through lately sales and now i'll wrap this up by talking a
little bit about uh our media presence which is kind of ongoing upgrading and all that but you can see
that this is a live presentation by the astronomical league uh we also
have a youtube channel which we've been doing especially for the 75th year we've been uh creating a lot of videos for that
placing them on on the youtube channels videos celebrating the 75 years in some manner or other
um in fact uh david levy was on it last week and appreciate him for doing that so this is a really big
step for us to share the hobby with others get people interested tell people who we are and what what we
do um we also have a facebook page which a lot of this stuff will appear on the facebook page as well
um that's been going on for a couple years we tend to put on um things like these outreach downloads
with the star maps we put on advice how to find things in the sky we have
submissions by clubs and odds and ends that we put in about the hobby so we're pretty excited about that to
keep our presence out there and to keep people interested astronomic has been around for 75 years
and for my position my position i can see it being around 75 more
you know it's uh the nature of our hobby is something that will always be there
uh people tell me about observing this is earning that and how they failed to do this and they failed to do that they couldn't find this and i tell
them look you know it's it's going to be there next year you know give it another try the weather may be better maybe you'll have a different telescope
maybe you'll be in a different location be able to see it this stuff is always up there and think of really why
why you're doing this over this past year of course we won't go into everything
that went on this past year but a lot of people like going under the stars and just looking up and being amazed being in awe of what's up
there finding inner peace within themselves trying to find comfort and satisfaction and what's what's above
to make sense of our of our world and i think a lot of people really benefit from this
um so that's what the astronomical league is all about and the astronomical league is here for you
thank you terry thank you everybody for listening to me go on for probably way too long about this
thank you john and he said i get off this yeah we want to see your hat again yeah
Equipment Sales
there we go this is my other hat this is my warm
weather hat here yes you got your summer and your winter attire there
always prepare thank you john appreciate it thank you and i think one thing even
that scott could attest to too is what we are hearing is astronomy equipment i know when i try to buy
anything everything seems to be sold out everywhere i have to go on a search
sometimes i have to wait for a month or two to get equipment scott i'm sure you are seeing pretty
much the same thing aren't you with all of the equipment sales there's so many more people at this point involved absolutely the uh
the surge of people interested in astronomy in general because of i think due to the pandemic
due to the effect of people slowing down and taking time to either
reconnect with their interest in astronomy or discovering astronomy for the very first time
led to an incredible explosion in people being interested in backyard
stargazing and so people decided to get a telescope uh
maybe binoculars but if uh you just get the gear and you don't have
the guide okay uh it's easy to get lost in the
universe and so uh with the astronomical leagues observing programs
that that is going to be your uh that's going to be your source for learning this guy in the right way um
and to gaining a deeper appreciation of what you're seeing out there some some of these objects are very uh
challenging to find um they're very far away uh but when you do find them to learn
something about them to understand how many million light years away they are or
what's fascinating about them is is is really what enriches your knowledge of the universe that you're
connected to and that you live in and the astronomical leagues programs are second to none they have more observing
programs than any other organization in the world and so you you know joining
up through your club or as a member at large is very very important so be a member and enjoy uh enjoy your
universe in a way that otherwise you'll just be cutting yourself short
thank you scott appreciate that yeah it's i know i've been trying to order
different things and i'm on a waiting list sometimes so yeah and it helps to know
there's nothing like taking a telescope out and i've had parents come to me and say this you know my child's interested in
astronomy i don't know anything about astronomy how do why do i start i don't know what the constellations are
you know and there's a process you go through and it's like scott said if you don't don't know where you're
going you know it makes you really cut yourself short you need to understand what's up there and
how to get to it to look at it and then understand what is it i'm seeing and you know people look at the moon to
start off with and that's incredible because we can associate what we see with the moon but there is so much more
that is hid out there that is just fantastic so thanks scott
i appreciate that thank you what are the all of you that are out there waiting for your gear
uh you know it's going to take a while because the whole industry has largely sold out
of uh telescopes so so we're waiting like you are
thanks scott uh as john was saying we are or maybe it was chuck we are probably
over a little over eighteen thousand members and of those eighteen thousand members
we are broken up into ten different regions uh and each region has a few states to
it so we have local chairs or we have chairs of each region and we have their own officers of each
region and actually don nab here tonight is the chair of the merrell
region the mid-east region of the astronomical league and i have been on the website that
don has created and it is spectacular don is here to talk to you tonight about
what's going on in his region to show you some of the things if there are more regional chairs out there
watch this you'll be impressed with the website and everything that this region is doing so don take it away
Merrel
thanks terry i'm going to uh share my screen and i'm going to be bouncing around a
little bit between screens i have here but i'll start with the uh slideshow
kind of started right here so you know if you'd asked me
five years ago what merrell was i probably couldn't have given you an answer but about five or four years ago i started
to get these emails from a fellow named terry trees and he was the uh the chair of merrell so i
found out where merrill was from terry and i met him actually it'll be two years ago in july
at starquest which i'll talk about a little bit later in my presentation one of the large regional
gatherings we have so well best way to talk about merrell is probably to go to the webpage that
terry mentioned so let me do that can you see this on my screen
okay so this is the uh the website i created this our club i'm a member of two clubs in
the area we're about 20 miles west of philadelphia and we work with a local night school
uh to give astronomy classes in the spring uh so this then this past spring they said
they're going to offer a a website class i said you know what merrill needs a website so i took this
class and what you see in front of you is is the direct outgrowth of the
night school class that i took so i won't spend a lot of time on it but this is the best way to learn about
merrell uh i have a home page set up which is some quick links
all this stuff can be gotten to but a quick link to the astronomical league it will open up a window
dark sky camping when i put this together last fall the only one i really knew about was cherry springs state park
in the middle of pennsylvania but there are other places i've learned about getting more involved with the merrell
clubs this will link to clubs and this will link to the star parties i'll talk about a little later
uh you know i have some boilerplate things here about the astronomical league
but uh this is our region delaware dc maryland the bottom half of new jersey
pennsylvania virginia and west virginia uh this is right off the economically
website uh membership benefits the only one i'll point out here i'm not going to read this to you
but down here this is the one that is most important to me okay one of the benefits of being part of merrell and the league
is they're part of a local regional and national community amateur astronomers uh it's great to be
part of a group of people that have a shared passion so where are we this is the mideast
region there's only one club in delaware now there's more clubs but there's only one that's part of the al
there's one in district columbia maryland has uh eight or nine clubs i think
pennsylvania about a dozen virginia takes the uh takes the lead the virginia astronomy clubs is it's
about 13 or 14. i'm starting to add club logos
again the website is still under construction i build it last fall take a little break i'm going to start
populating a lot more things on the website but all these societies are here
virginia is probably the largest pennsylvania second largest uh i'll talk ramona about aap
astronomical pittsburgh uh mention them when i go to my slideshow
events i'm going to be filling this up because i'm getting ready for this this evening i found about a lot more
events than are listed here so i'll be talking about those in a few minutes
i put resources here uh stuff for kids and in our part of pennsylvania we seem
to have a lot of girl scout activity so uh my wife and i took a course from the
night sky network and the astronomical league of the pacific to help us learn more about
things for girl scouts so i have a couple of links here that goes in nice guy network and seti
we have other things for kids of course observing aids some of the typical ones sky maps
sky and telescope and uh even though maybe you maybe you can't buy stuff right now at least there are
links here to some of the major manufacturers i'm going to be populating this with a
a lot more a lot more uh suppliers and i haven't gotten any submissions yet
but uh i have a spot for anyone in merrell can submit uh images to me and i will
put them here i have a number here from uh delaware valley astronomical uh
amateur astronomers they uh they're almost a sister club in a way three or four of the clubs in southeast
pa we really work together on uh on uh astrophotography and including the club in delaware and
uh on some some events so i posted a few images from uh
from some of these folks nothing you haven't seen before i'm sure
and of course every website needs a contact page and we have that also so
that's probably the best way to reduce merrell that that's our group we're about 37
clubs so i'm going to go one other share we do a facebook page i'm not using
facebook page a whole lot um [Music]
it's mostly a way to get us get people to the website but i do put some posts here we have some people following it it's
great and i get these uh these sheets from john goss and i i post them up here
and i get a few people hitting on that they come and look at it so uh but i started out trying to do
just a a facebook page for merrell and it's so limited that i figured i had to do a
website so uh so let me go back to my uh powerpoint
a few slides to share um so i have 37 clubs uh and you know i
Amateur Summer of Pittsburgh
i asked for input from some of the clubs i got some nice responses so i think i mentioned aap amateur summer
of pittsburgh associate pittsburgh uh that is actually the uh the club who the previous chair terry trees was part of
and he tells me that that that the uh their club was a charter member of the al
and they hosted the first alcon to best of his recollection okay um goddard club i don't know a whole lot
but you know this has got to be a fascinating group of people all working at uh goddard space flight center or if you
can't have a better collection of astronomers than that i don't know where you're going to find it
so that that's a maryland club novak i got a nice response from the
Northern Virginia Astronomy Club
president of novak that's northern virginia astronomy club i checked their website amazing they have over a thousand members
that's a big club the club i'm in um chester county we have about 125 which
as we've heard mentioned tonight we're growing five six years ago we probably were in the 60 or
70 member we're up to 125 now i know delaware valley is growing uh
very quickly so we're seeing it i think novak is seeing it also
and they host a lot of amateurs on the event through the year i'll talk about the almost heaven start party
in a few minutes that's down in west virginia on labor day weekend and we'll show up when they do it this
year we hope so uh and they they monitor multiple dark sky sites through virginia
so they cannot they can the thousand members need to have more than one site that's for sure
uh then the roanoke valley you know and they we pretty much share the same experience here virtual meetings that's
what our club is and delaware valerie violet club is doing and delaware club is doing
uh they're seeing you know uh rbas is seeing increase in astrophotography i
would say the same thing for our club and the clubs in the area here they're doing meeting on zoom as every
club that i know of is doing in one zoom and we all seem to have the same idea we have about a half hour of social time
of chit chat before a meeting and then we uh then we do uh then we do a regular meeting we had a
lot of fun at christmas time we had our virtual holiday party got the idea from john goss of doing uh
a uh limerick contest and we had a quiz and of course the prizes for that were astronomical league
calendars so that was very well received by our members so uh i do want to mention delaware valley
Delaware Valley Amateur Astronomers
amateur astronomers as far as the pandemic what are we doing during the pandemic the current issue of the reflector had a
wonderful article written by uh three members of dvaa as we've
referred to them delaware valley amateur astronomers i'm not going to go in detail here but you can see they they set up here's al
alain perdi he is the regional representative to the astronomical league from merrell so he's
an officer of merrell and jan rush is uh our secretary for maryland she's also vice president of
dvaa so they would set up in a parking lot by a park a
museum park you can see they would rope off areas they would have projectors with a number
of revolution imagers or webcams taking pictures you can almost make out
jupiter and some moons there but they went through a couple of learning phases like the first time they
hooked up the projector it ran they had an inverter and ran the battery the car down in a very short amount of
time so they found they had to keep the car running and they got a sound system and you know
they had they only allowed people there that had registered so they controlled attendance and when people got there they handed
out uh masks they handed out hand sanitizer so i really encourage any club that uh
that is listening to if you wonder how to do this if you have somewhere you can do it which is a big if
uh dvaa does have a place i can do it get the latest issue of the reflector and read
what dvaa did they did a wonderful job despite having a pandemic going on
they've had i think three events now so far regional events i'm going to talk about
Regional Events
now the rest of my present day just a few regional events that are going on we hope are going on in 2021
now nei that's not in merrell but it's pretty close uh and that is going to be uh virtual
this year and you never know who shows up at these places but uh but there's a guy that should have there's scott
i'm not sure what you this is okay they let anybody in i guess right that's right but uh this is a picture i
took back from 2012 and uh it's a wonderful event like we've heard people talk about earlier tonight
it is like the biggest candy store for astronomers you were ever in so uh when they get back hopefully next
year to having it live i really encourage everyone to go to it is just leave your wallet locked up in the
car is what i would say to do you want to be able to have buy gas to get home
Novak
and then uh novak very active club again over a thousand members right now they have a plan but i haven't
gotten confirmation over astronomy day may 15th they do that in a park in
midland virginia where you can see their sign the back of their sign here they set up and uh
do a whole astronomy day event jerry springs you know i've not actually
Cherry Springs
been my wife and i haven't been to the cherry springs star party we've been to cherry springs many times our club goes up along with
uh the dvaa we tend to go up there together and set up in the field this
if you haven't heard of cherry springs state park it's in the middle of pennsylvania it's right between the middle of nowhere
and where the heck am i that's where it's at it is in the middle of nowhere literally and you know a lot of times you see
pictures like this and people say well it doesn't really look like that because it's a time lapse well actually that is just about what it
looks like at cherry spring state park it is one of the darkest sites on the east coast
uh they have two events there june 6 to 10 and then there's one called the black
forest star party also at the state park usually that's in october or september it's not scheduled at this time but uh
anytime there's a a dark window you'll see maybe not this many but you'll see quite
a few folks up there and you'll see me and my wife and people from our club up there this summer i'm absolutely certain we went up last
summer being very careful not sharing eyepieces wearing masks and everyone's very
respectful of the pandemic restrictions but uh this is supposed to be a wonderful event i hope to get there sometime
but i'll go to the park whether it's an event or not
Green Bank Starquest
and then uh we actually did go to this event uh in 2019 this is at green bank starquest
uh again a long-running event it is located at the world's largest steerable
radio telescope and you can tour this thing when my wife and i some of us toured we got up to
this level they had problem with the elevator but others got up all the way to the very tip top and it
is high you're in a radio free zone even if you turn your cell phone on which you're not allowed to do
you wouldn't get any signal it's a radio free area even the uh there's a in the
visitor center here there's a cafe but their um microwave oven isn't a faraday cage
the only contact with the outside world you can get is to go into a room that is entirely lined with conductive
material i figured it was copper or aluminum but you're in a gigantic faraday cage door to access some computers to get the
internet uh the camping looks a little sparse i took this on the last day as we were heading out the field was
pretty well filled up so uh but there's plenty of room and uh there are speakers every night
they have a wonderful uh raffle my wife and i put it i put i probably put 50 bucks
into the bucket for the uh astronomy quilts and we did one actually won two of those it's a wonderful
wonderful place the people are great there so this is green bank it's right now scheduled for july 7-10 and we plan to
be there the almost heaven star party this is run by novak and this is
Bruce Mountain Center
actually just not that far up the road that's bruce mountain center in west virginia it's not that far from uh green
bank another very large part they have it over labor day weekend and you can see the kind of dark sky
they have and a large field they have lectures here's the novak sign
these things i think they call a yurt it's uh it's where they have lectures and they even they have so many people show up
they even broadcast uh the sound and video outside of the uh the lecture hall
but that that's that's a definitely bucket list place to go to also
York County Star Party
uh york county star party people might remember this is the mason dixon star party it has a different life now as york
county unfortunately can't cancel last year we have plans to go there's going to be
two events i think the main ones in october uh this year we should be clear by then i really hope
but uh this is uh not far from harrisburg pennsylvania you're there near the susquehanna
looks like a beautiful spot to set up a big sky uh again novak shows up here again this
Star Gaze
is uh what they call their star gaze this is in a plan now for uh october
and it's a it's a big open start and the last one uh this is not a
Chapel Hill Star Party
merrell club but it's in virginia which is part of merrell so i included it because it's a very large
uh party staunton river star party hosted by chapel hill in north carolina this looks like
another big wide open field and they have lectures and guest speakers and all those things so it
looks like a really uh real nice event to go to also so that's merrell that's that's any
questions about it well no i don't see any questions right
now i think they enjoyed your program though yeah well i finished just about on time too
yeah done thank you don that that is great i know the great lakes region will be in touch with you about building a
website definitely happy to help happy to help any region any club build a website i can help you with that uh it's all
menu driven it's not that hard but it does take some time so yeah you did a great job on that
thank you so much for your talk i really appreciate it it's very interesting and it's good to see some star parties
that could possibly be coming up because i think we're all ready to go again yup we're hoping
yes definitely so all right um scott why don't we do about a 10 minute
break and we'll come back to rachel okay all right okay all right we'll be back
shortly
his accounts of identity and direction including never seen before footage of the mob
invading the capital
oh
okay
wow
one
no
so
bye
you
well we're back um hope you had a nice little break there and
what's what's up next terry all right thank you scott um i would like to introduce rachel
cianetti she is a sophomore at the university of kansas studying physics and astronomy she has given three talks
for a local astronomical group this astronomical society of kansas city
rachel is currently on a research team studying galaxy velocities and the hubble
constants with physics and astronomy chair at ku
hume feldman rachel is looking forward to the talk about dark matter and dark
energy and can't wait to share her enthusiasm with others about the beauty
and mysteries of the universe so rachel thank you very much for being here
and we look forward to your talk hi thank you i'm looking forward to it
um maybe the most out of anybody yeah um as she said hi my name is rachel cinetti
um i am a sophomore at the university of kansas um i lived here before i went to this university so i've been in the
astronomical society of kansas city for i think around two years at this point
um and every time i get to do a talk it's so great so i'm just really excited to be able to do this again um i'll share my screen
here um is my audio okay am i loud enough um
okay great okay so um i included both the al and the askc
logos in here i'm exceptionally excited that it's the 75th anniversary i just think that's so cool
um and all of the talk prior to my presentation that i'm about to give about how enthusiastic everyone is in this
club just brings me so much joy um because i think that especially in the past year astronomy
and physics and everything about the universe just brings people a lot of escapism and a lot of hope so
i hope that i can teach at least one thing to everybody listening that makes them
interested and invested in this um so also as mentioned i am doing research
um with my university so at the end if anyone has questions about that it's not something i'm going to talk about
but i can if anyone's curious and finally i am a sophomore as it's been mentioned a
couple times now so definitely i'm no doctorate i'm not an expert yet by any means but i would love to
share what i know and um i would love for a lot of questions to be asked ideally because
um for me being an aspiring cosmologist um it's much more exciting to not know
things than to know things um so that's also going to be the point of this presentation is
not necessarily all the answers about the universe because we don't have many um but it's going to be very open-ended
and about the things that we don't know because that's the best time to get involved is when the game is going and we're trying
to figure things out so we're going to be talking about dark matter and dark energy which are two gigantic question marks um
in terms of explaining the universe um and these are ongoing things um they're not historical at all um the
study of cosmology has really only been in practice and taken seriously since about the 1960s
so this is extremely new and that's why it's so exciting
so um i just wanted to include this at first this is an illustration that's supposed to represent the whole universe
in one picture um starting from the earliest thing we can see which is the cosmic microwave background and i'll talk about that um
all the way up to our solar system obviously not to scale um we may feel like we're that big in the universe but
we're not um this image goes logarithmically in scale so each little bit um is an order of
magnitude smaller but i just think this image is really cool because i think everyone listening
right now is here because we're all in awe of the universe and how beautiful it is so i figured it had to start out on this
note but we're gonna go over um all the things that we can't see in this image
specifically dark energy and dark matter are both called dark because when we're looking at this image we can't see them at all and we'll get
into what that means so we're going to start out chronologically with the title with dark matter so
your first question might just be what is it and i can't answer that question um no
one on the planet can yet but we do have a lot of good ideas and we do know that it's there so there is a difference between
knowing what it is and knowing that it's there the same way that in the dark you might be able to hear someone is in the room
but you can't see them so that's exactly what's going on with dark matter but
it's not like a person speaking to us it's not that obvious so how do we know that it's there we're
going to learn about that we're going to learn about the first time that dark matter was sort of discovered
and though it wasn't called that at the time it was technically the first observation
but first off let's talk about what it means when we say there's matter that we can't see it
sounds really counter-intuitive because everything we see is matter everything is visible and the universe
is partially made up of that stuff it's actually not entirely and that's the point of dark matter
the stuff we can see the stuff that i'm made of and the stuff that your computer screen is made of is called luminous
mass which means that it's protons neutrons atoms and these particles interact with light so when
photons hit it or pieces of light hit it it reflects that light back and makes itself visible as opposed to
something invisible where the light just goes straight through and you can't see that there's anything there um so when we talk about luminous mass
we're talking about this stuff on the periodic table and when we're talking about dark matter it's a little more apt to call it
invisible matter but we named it and got stuck with the name happens a lot in astronomy
so we call it dark matter so we see effects of it even though it's
not luminous so this is the unknown stuff is dark matter and it's just a title for
um it's almost a placeholder for we know something's there but we can't explain it yet um so it's a very new very developing
field and the image to the right is from the millennium simulation which is a simulation of dark matter so
it's made visible just for us to comprehend but this is what the structure of dark matter looks
like on the largest scales of the universe it looks like filaments in this way the way that
it's distributed as opposed to normal mass where we see a lot of it in stars or in objects dark matter is
distributed in this way and matter on large scales actually is distributed in this way too um it follows this sort of as a map
um but we'll talk about that as this goes on um but essentially this gives you a visual idea of what truly isn't
visual and i was impartial to using a millennium simulation picture because i've worked
with small parts of the simulation before so it's really cool
but we're talking about this but how do we actually know it as i said we're going to talk about how
it was discovered and this was done in the 1930s so we're talking about one
methodology while in the present it's been confirmed with many other methodologies but i thought it would be best to start out
with the first one that happened so we can discover it the same way that um astronomers did in the 1930s
so we talk about this missing mass we can't see it but we we see its effects but what does that
really mean how do we do that well there's essentially three steps the first step is to measure
mass that's present by observing how interstellar objects move around how they behave how they're influenced
by their surroundings so that's measuring more acting mass than mass that you can see
the second step is to measure how much mass you can see not measuring effects or anything
indirect that way but just looking saying i see this too many objects they weigh this much add it all together
that's how much mass there is um and three you compare and up until we discovered dark matter
we expected these things to be the same because why wouldn't they why would there be some weird imaginary matter
pervading the cosmos for no reason that we couldn't see we hadn't even thought of it um but we're gonna go through
these three steps and see what happened and what was discovered so first of all um we're going to
measure the mass in this indirect way where we conclude a mass of a galaxy cluster that's going to
be our subject which is a big group of galaxies gravitationally bound together sort of like bees around a beehive
that's a way to picture a galaxy cluster we're going to measure the mass of that galaxy cluster not by just adding up all
the galaxies as weights but by how they're acting but how do you do that
that doesn't really make intuitive sense to understand this i'm going to go over some basic ideas first
because you never know who's listening and it's always valid to not know it's always much better to not know and admit that you don't
know so we're gonna go over some basics the basic number one is mass and matter
aren't the same thing um you might hear them used interchangeably but they're not quite
mass is just the quality of having a gravitational pull or curving space time into a well um
but matter is it has mass um but it also is you know in the way that
we think of luminous mass or matter that we can see so on the left you can imagine that yellow ball
is the sun with its gravitational pull curving space time and making things orbit around it um so that is matter and
it has mass but to the right there's mass there but there's not necessarily any matter so when we talk about
measuring the mass without just counting how much weight of stuff there is um sorry we're talking about the thing on the
right basic number two is that mass and matter consequently create an
inward force which is that curve in space-time that i'm talking about um so think of a trampoline
it's a very basic example if you have a trampoline and you put a bowling ball in the middle and then you drop a marble
or you roll a marble at the edge it will go in towards the center and fall towards the bowling ball
because the bowling ball has a lot of mass so it's creating an inward force that attracts other objects with matter and mass so
objects in space are the same way as you can see in the picture to the right and the more mass you have the more pull
you have on other objects with mass basic number three is that motion
creates an outward force so if you think about the marble again if you just drop it very gently it'll go straight towards the bowling ball
but if you roll it with a bit of force it might go around in some circles before it gives way to the bowling ball's attractive force so
motion basically in the context we're talking is the antagonistic force to gravitational pull the more velocity
something has going around a massive object the more ability it has to fly away instead of falling towards the center
so we have these basic ideas but how do we combine them in order to do what we were talking about and measure the mass of the galaxy
cluster well first let's think of something much more simple because this is always what
um you should do in physics to start with a very simple model to understand because that's always very effective
something you can think about as opposed to a big complicated galaxy cluster is a ball on a string
so imagine you have a certain type of string of a material and then you have a ball that you're using
continuously the same ball and you spin around in a circle like this and say your string is too weak and it
breaks it snaps and the ball flies away out of the orbit well you didn't successfully hold the ball in because the attractive force
holding it in this loop wasn't strong enough so then you switch to a stronger string and maybe it breaks again and then you
switch to a stronger string and finally it holds the ball in that orbit so you can figure out
based on how the ball is moving how strong your string needs to be or the qualities
of the ball tell you how strong your string needs to be in order to keep it in so you say okay the string has to be
at least this strong if not more strong to make this system work and
in a sense that's exactly the way that the galaxy clusters are except the galaxies represent a ball
and the inward force of their mutual mass is like the string so we can't look and see the string but
we can see a bunch of galaxies and how they're acting specifically their velocities
and we said how the velocity is the antagonistic force to the string or the gravitational pull
so we look at a galaxy cluster we look at the galaxies we say okay on average they're moving this fast
which means that in that cluster there has to be at least this much mass to hold them together in
this cluster otherwise they would fly apart and there wouldn't be a cluster at all because their mutual mass wouldn't hold
them in so this is how we can calculate um indirectly how much mass
there has to be in a galaxy cluster because otherwise we wouldn't see a galaxy cluster at all
so that is how to do that first step you find the outward force which you can observe um by measuring galaxy
velocities and if anyone is curious as to how you do that i will kind of mention a tangential thing later
but if anyone's curious totally ask um in a short and short way it's done by using
redshift um which indicates how fast the galaxy is moving um typically away from
you typically things are redshifted four reasons we will get to spoiler alert but also things can be blue shifted if
they're moving towards you and the amount that they look reddish or bluish tells you how fast they're moving so
once you know how fast they're moving in general you know how much mass there has to be in that cluster
so you've gotten your cluster you've figured out how much mass it has write it down and now we move on to the second step
which is measure how much mass you can actually see um so we're not using as complicated of math here we're just
saying okay we see this much light how much stuff is there and
this is quite simple um when you do it in a rudimentary sense um because there's a direct relationship
or a very good relationship between mass and luminosity um for main sequence stars which
comprise a lot of the stars in the universe um so you can see a linear relationship here which just
means that if you see something with your telescope that's say a thousand solar luminosities or a
thousand times the brightness of the sun you just use this graph and say okay it's about
10 solar masses and so you can look at your galaxy cluster collect all of its light
and say okay it's about this bright so it should have about this much mass
and for the purpose of what we're doing you can make a pretty darn good guess with that method so you write down your
second thing you write down okay we used our telescope optically we analyzed it and this is how much mass there should
be and the final thing you do is you compare them because they should
be the same right except they're not and actually they're very drastically different
the first result tells you that you need way more mass than you're seeing optically or when you look at the galaxy
and you collect the light you're only seeing a tiny bit of mass compared to what you know according to the laws of physics
needs to be present in order to make that galaxy cluster exist
but the issue is we don't know where this mass is coming from because we can't see it we were literally blindsided by this
when we discovered this so this is exactly the methodology that was
used by fritz wiki in 1933. um very simplified obviously but he did
basically the same thing with a specific cluster called the coma cluster
um so he did what we did he measured the mass and then the luminous matter and he was
like wow those are not the same at all what is going on um and his specific results found that
um there was a discrepancy by a factor of 50 times as in there was 50 times more stuff that
needed to be there as compared to what we saw so this pose is a huge issue um and this
is technically the first observation of dark matter although at the time people didn't really pay attention to it
um for some reason it just didn't come to the fore in astronomy quite yet um and then there are multiple other
ways of figuring out that dark matter needs to exist that come decades later but this was truly
the first discovery so there's a lot more that we know today
um one of the most important things that we know is that dark matter exists everywhere and in galaxies not just in
galaxy clusters because there was no reason for them to assume that it was everywhere when they first discovered it in those clusters
maybe they thought it was something unique to clusters in the sort of medium in clusters but no
it exists everywhere in that filamentary sort of way we talked about and so it exists in galaxies
and namely it's actually extremely important to galaxy formation without cold dark
matter oops dark matter spoiler without dark matter um we wouldn't have galaxies in the way
that we have them we wouldn't have galaxies arguably at all um because dark matter settled into that
filamentary structure before luminous matter or the matter we exist in
um fell into structure at all and basically regular matter has to fall
into a gravitationally bound structure in order to create things like stars and create things like galaxies and planets and things for us
to exist on and the only reason luminous matter was able to do that is because dark matter
did it first and then attracted luminous matter into itself to build that structure and we know it
exists in galaxies because of as i mentioned a discovery that came decades later about galaxy rotation
curves which essentially is this plot here which means that when you have a galaxy
most of the mass is concentrated at the center and it gets less so intense as you move out towards the
edges of the galaxy think of spiral galaxy one that's spinning around its center um so essentially when you have less
mass you have less of that attractive force that we were talking about um so things that are at the edge are
not going to be moving as fast because they're not as tightly bound to this attractive force in the center
so what you would expect is the further away you move from the center of the galaxy the slower objects are going to move um
but what we eventually found out is that that's not true um when we look at spiral galaxies it's
sort of it reaches a certain velocity and then as you move away from the center and move away from that attractive big
piece of mass it's not slowing down it's acting as though it's much closer to the central
mass than it is which also indicates a strange occurrence a problem the same way that
we found in the clusters because essentially what this is implying is that there's more mass present there's more pulling force making things
go faster than we see so it's sort of the same issue and our
own milky way that we're sitting in right now is 95 dark matter and we think that dark
matter in spiral galaxies exists in this sort of sporadical halo shape
what we also know is that we know it's probably non-baryonic which is a fancy way of saying that it's
not made of protons and neutrons um a couple reasons we know this are for one
we would have noticed backlit areas which means that if dark matter is just regular matter
like us that we're made out of um we would have seen at this point it backlit which means that um in the
dark once again we're going to use an example of having a friend um in the dark if they shine a flashlight at an object
behind it towards you you can't see the object but you can see a silhouette um so if dark matter was made of the
stuff we're made of or the stuff um of whatever your friend is holding and shining a flashlight behind we would see a silhouette but we don't
which indicates to us that light doesn't go around it it goes through it and also when i say not enough elements
in this slide what i mean is that particle physics was able to predict with very good accuracy
based on a lot of things we already know about physics how much of each element there should be in the universe um
and it was truly very accurate as in there's about 75 hydrogen and 25 helium
um so if we were to suddenly say oh there's like 50 times more matter here then you would suddenly
have a huge issue with the ratio of the elements because that doesn't quite add up with particle physics
so there are two very compelling reasons why it's probably non-varionic which means a different type of particle
than we're used to we also know as i spoiled earlier that
dark matter is agreed upon as being cold which essentially means that it's slightly more dense
than the regular matter that we're used to and what this means as i said earlier when i said that it dictates large-scale
universe structure of regular matter is that in the early universe it was very hot
um the early universe was very active very hot um particles were whizzing around particles of matter and dark matter and
when things are whizzing around and they have a lot of heat they don't cool down and calm down enough to coalesce into
a gas cloud and then a star and then a galaxy objects can't form if things are too energetic um
so when it was hot like this dark matter since it's more dense and it's cold quote unquote um which essentially
means it's affected less by the radiation it's not affected at all by radiation because light goes straight through it um it was able to calm down in this
very radiative environment and settle and it settled into this structure and
the universe was smaller back then but it still wrote this sort of mold
um into the universe that has stuck as it's grown and as we talked about how areas of mass
attract more mass um even though the matter that we're made of was whizzing around at this
point eventually it calmed down enough to fall into these areas of higher mass of dark
matter so dark matter was sort of telling and is still telling luminous matter where to fall
gravitationally and this um governed galaxy formation it
provides a very good theory of why galaxies form the way they do because they're forming according to this filamentary structure
what we don't know today is what it actually is um we know that we call it something but
we can't say exactly what it's made of um there have been a few options proposed some much more favored by
scientists than others and it's constantly changing um in terms of like specifics um but a few
of the options that have been proposed are machos um cosmology is great with acronyms
it stands for massive compact halo objects this was proposed by people who
disagreed with the majority and said that maybe it is baryonic or maybe it is made of regular
matter and when we see that halo structure of stuff around a galaxy maybe it's just a bunch of matter
objects that don't give off light such as red red dwarves which you can see here or sorry
brown dwarfs which are objects that almost became stars but then they didn't so they're just
big pieces of mass that aren't giving off light because they never started undergoing fusion as a star does
and another type of object is very very small black holes um that sort of when you add them all up
they would create a large amount of mass contributing to what we're seeing but as
we said we can reasonably say that it's probably not those because we would have seen them backlit by now
so not many people are in favor of this theory at this point another theory um introducing another
great acronym is either wimps or axions wimp stands for weakly
interacting massive particle which essentially means that it interacts gravitationally but not with
light the same way that we saw that image of a gravity well without anything we could see sitting inside of it um and another
option is axions and these are both hypothetical particles that
are sort of what people think of when you say dark matter you think of a particle that is invisible and neither
of these particles have been directly discovered yet but specifically axions have been theorized by particle physics
to solve other problems that have nothing to do with cosmology so basically people
have a lot of faith in these because there are two different areas of science one being cosmology saying we need a new
type of particle and particle physics saying we also need a new type of particle um so people are searching for these
because that seems quite compelling that two separate areas are sort of looking for the same thing based on theories
the final option is somewhat still popular but it's not nearly as popular as the
particle sort of idea um it's called modified newtonian dynamics um everything we've talked about has to
do with ideas of gravity and mass and those are based off of newton basically um the guy that said
why does an apple fall from a tree or allegedly said so some people think that theories of
gravity are actually what need to be amended that there's not a new thing but just our understanding of physics
isn't quite right and it's always good to have people saying things like that
in cosmology because you should never get too attached to one idea you should always keep your mind open that you're doing something wrong um
but in general based off of a lot of evidence we've had a lot of which i've mentioned people do think that the particle
argument is the most compelling because mond is a little finicky in terms of describing
when it acts the way we expect and when it breaks down and starts acting differently and why it would do that at that certain
point for example um trying to determine why the center of the spiral galaxy acts the way that we
expect with traditional newton but somewhere along the way to the edge it would change
so the most popular theory is the particle idea and that's why there's a lot of searches
going on for them right now um here's a map of a few underground detectors which essentially the idea of
those when you're looking for dark matter is these detectors are underground because they're avoiding
interference from cosmic rays which are energized particles coming down onto earth's surface from space
so they go underground to avoid this interference avoid these particles that are hitting everything that they're trying to look at
and they're just huge bats of liquid um liquid that have a lot of sensors
around them so they can look and see on the very small scales what's going on because the idea
is if we're looking for one of these particles eventually just one has got to move and gotta hit
one atom in that liquid and it will impart some momentum onto this particle
and make it glow a little bit because you're giving it energy basically you're giving it heat in that collision
so these huge containers are built with tiny sensors looking at all of the atoms
in hopes that they will see one of those indications that light flash that indicates a hit
but the tricky thing is as i mentioned they're built underground to avoid cosmic rays which are other types of particles that
would do the same thing but we know what those are so we don't want them we want to be able to single out the dark matter
it can still be complicated because there are still particles that can get underground and give those signals but the search
for dark matter is very intense because it's it seems very ripe for a huge discovery
um so that's why there's so many and i even think this um map is a little bit old i think they're probably more now
um but essentially that's how that's one way to search for them and another way to search for them since
we mentioned that their hypothetical particles proposed by um particle physics in an isolated way
is that we can look for them um in particle colliders by trying to collide particles and see
if those ultra fast speed of light almost speed of light collisions create these particles in the products
so that's another way that we can look for dark matter so those are the two basic ways that people are searching and people are searching it's very fervent
very active very exciting um one of my personal goals is to go see one of these
so essentially that's dark matter and that's where we stand currently and what we found out is that 22 percent
of the universe or about um is dark matter and only four percent
of matter in the universe is our matter our regular matter so that was a shock to
find out as i mentioned before that dark matter drastically outweighs regular matter um but when we look at the universe
pie chart as a whole like this there's something else that's actually taking up 74 that isn't dark matter and
that's where dark energy comes in and the 74 number is a little dubious at this current point
but for now it'll do it gives you the general idea we'll talk about why the 74 is a little dubious um but now
we're moving on to the second half of why we don't understand anything that's going on in the universe
um and why we're trying our best too is dark energy and you may be thinking this is a little
bit strange you're talking about things even if it's something we can't see we're talking about
things and objects in a way that we're familiar with how is it that the universe is comprised
of just energy and the only thing i'd like to bring up here i try not to include equations
but i hope this one is acceptable um e equals m c squared which essentially
means energy equals mass times the speed of light squared which means that energy and mass are kind of the same
thing they can interchange between each other if you give mass a lot of energy or a lot of speed i'm sorry so
essentially energy and mass on either side of this equal sign can sort of be like the same thing
um so if it sounds a little strange when we say that 74 of the universe's energy which you
typically think of as intangible and sort of just very separate um that's
something that uh you kind of have to get used to wrapping your head around um but essentially 74 of the universe around that
is dark energy so if we're going to talk about dark energy let's talk a little bit first about just
ideas of the universe as a whole um because dark energy has to do with studying the universe on
its largest scale which can lead to questions like is the universe finite is it infinite is
it expanding is it contracting is it staying the same size dark energy dictates our answers to
these questions um so let's go over what some people thought before we knew anything about dark energy
um the first thing is the greeks um the greeks argued that the universe was finite which means that it's a
certain size and it has a boundary and it's not changing size because they said they saw a bunch of stars in the
sky um probably much more than us because darn light pollution um but they saw a bunch of stars in the
sky and they said if the universe was infinite there would be infinite amount of stars so the sky would just be white
it would be full of stars in every possible place so they said the universe must be finite isaac newton
who as we've mentioned many times is an expert on gravity said if it's a closed container and
there's a bunch of stuff a bunch of mass on the inside with gravitational pull it would pull in on itself and it would
make itself collapse and luckily we haven't experienced that yet hopefully won't
um but so that propelled him to say that the universe must be infinite because otherwise it would be collapsing on itself and um
structure wouldn't have been able to really form and by the time albert einstein was thinking about the universe as a whole
um what people knew is that first of all if there were infinite stars we wouldn't
see the the sky fully lit up because stars get dimmer the farther away they are the same way that
headlights don't hurt your eyes from a mile away as they do in your face so there could be infinite stars and we
still wouldn't have that bright sky the greeks thought of um and also they're dimmed by things
like interstellar gas and dust but what einstein and his colleagues usually thought is that the universe was
in a steady state which just means it exists it's basically a certain size if you want to put it
that way it's not growing it's not shrinking it's just there um and that's what a lot of his colleagues thought and that quickly got
turned on its head um in 1929 by edwin hubble because edwin hubble discovered first of
all not only that the universe is more than just our galaxy because if we can take a little sidetrack up until this point people
thought that the milky way was the entire universe and of course now we know that there's so many other galaxies that we can't
even fathom it um the people thought the universe was a whole lot smaller up until edwin hubble discovered that
the universe is bigger than our galaxy by finding a way to calculate distance and saying
holy heck the math is telling me that this thing i'm looking at that i thought was really close to us is really far away
and then he found a bunch of things like that and he said okay the universe is much bigger than we thought um and along with this discovery
and along with the methodology he used to deduce that there are other galaxies he figured out that the universe is
expanding um constantly and this led to the idea that was actually partially credited to
his name is french i think it's like george the mates he was a catholic priest and he
contributed to this idea of a big bang because he and others thought that if the universe was expanding
constantly that means that if it was this big one day and then the next day it expands
some and it was this big then that means that yesterday it was smaller and that means that the day before that it was even smaller
and you can just take that to the logical extreme and say okay at one point it would have just been infinitely small or it would have been
very very small and um he was actually initially because we hear about this so often today the
big bang theory but he was actually rejected for it initially because people thought that he was just a catholic priest trying to
insert a genesis context into the universe and astronomers were like no no no we won't have that which i
think is really interesting because it turned out that this is the most compelling idea um but we'll talk about how edwin hubble
figured out that the universe is expanding because i'm sure you're wondering that it's not intuitive at all um
and especially these two people vestas leifer and henrietta levitt are very important to this discovery that edwin hubble made
so festus leifer and henrietta levitt both essentially were astronomers that created
powerful tools that edwin hubble could use in this discovery the first one is by vesta slifer who
realized a relationship between redshift and blueshift of objects and their velocity
so essentially if you look at an object in the sky you can collect its light and in a very simple way objects have
a spectrum and they usually have a line in that spectrum um stellar objects
that say just imagine it in the middle um so there's a light spectrum and there's this black line in the middle
and when you take the spectrum from that object and you separate out its visible light into the spectrum
this line might be moved to either the left or the right as in the red end of
the spectrum or the blue end of the spectrum um depending on its motion and if anyone's curious about the specifics of
that i can go into it but essentially when you look at an object and it seems a reddish or bluish
that can tell you reddish it's moving away and bluish it's moving towards you because this is called the doppler shift and it's the same rule
that governs why when trains come towards you um they sound like they're they're increasing in
pitch um the train horn sounds like it's going up and as it's going away it decreases in pitch
um maybe a car horn is a better example i don't know how often people use trains nowadays but you get the idea
um so that happens with sound waves because when it's moving towards you the train which is emitting the sound
wave is crushing against the sound wave as it's traveling and basically squishing it on its way to you yeah
but then as it's moving away and it's emitting this light it's moving away and the light catches up a little bit which or sorry the sound wave um which
stretches out a little bit so when the sound wave is squashed it sounds higher um because it's a higher frequency or
yeah in a shorter wavelength and when it's moving away has a lower frequency so it sounds lower and if you can imagine that then you
understand what's going on here it's the same exact thing but with light and this is extremely powerful
because when you look up at objects in the sky you can't see them moving um they're too far away it would take
too long it's not feasible you can't just look and see a star moving across the sky if it's too far away
so this is an extremely powerful tool it's completely essential to all astronomy um
and the next tool was found by henrietta levitt and it indicates distance and this is also just extremely
extremely important to everything that we know hubble would not have been able to do what he had done without
henrietta levitt's discovery of what are called cepheid stars which essentially means they're stars
where the period and the luminosity is related and when you're calculating what this is important for which is distance
um the two things you need or i guess the one thing you need is you look at an object and
you figure out how bright it is regardless of how far away it is from you not how bright it is
um and maybe it's dim and that makes you think oh it's far away but how bright it is on a non-relative way
so it's absolute brightness um and when you know it's absolute brightness you can compare it to how bright it
looks to you so say you know how bright a flashlight is and then you're seeing it far away from
you and it's dim that can give you an idea of about how far away the flashlight is so if you find an object in the sky and
you know how bright it would be if it was right on your face and you say okay it's this dim that gives you an idea of how far away it is
and this is just so incredibly important um and that's hard to usually do because when you look at an object you you
don't really know how bright it would be if it was right in your face you have no way of knowing um so when you look at a star you might
say it's bright and it's far away or it's dim and it's close prior to this it was really hard to tell
the difference unless something was very close to us um so this gave us an ability to measure
distances to things that were far away because if we could find one of these stars essentially what a cepheid is is it
increases and decreases in brightness periodically so say it's going like this and it's getting bright and dim and
bright and dim however fast it's doing this tells you about its absolute brightness so
you can see here that the x scale is how long it takes for it to go through one of those
bright dark bright cycles and then the y-axis will tell you its luminosity so this is
just an extremely powerful tool because now we can know distances so long as we find one of these special
stars that goes bright and dark and bright and dark so edwin hubble using these two methods
realized that there's a linear relationship between velocity and distance of objects
specifically he was able to find distance to a bunch of things using those stars and then he assessed their redshifts and
he plotted them against each other and found that it's always true or almost always true that the farther away something is
the more it's redshifted and remember that when something is reddish that means it's moving away and the more red it is the faster it's
moving so the further away something is it's more redshifted which means that it's moving
away faster and this is essentially how we deduce that the universe is expanding
in all directions at once um you may think that this indicates oh why is everything moving away from
the earth why is the earth special why is everything receding away from us
but actually that's just how it appears because the universe is expanding in all places at once
um and a good way to visualize this a metaphor that i wish i could take credit for
is raisin bread that's cooking in the oven so when you have raisin bread like this
think of the bread as space and the raisins as galaxies so you put this in the oven and it
starts cooking and the bread will rise everywhere all at once just like space is and these two
galaxies will separate and these two galaxies will separate and these two galaxies will separate and
these two galaxies will separate and you can think about it this way that every galaxy in this bread or in this
space every raisin in this bread i'd better keep the two straight they think that everything is moving
away from it um to each of these raisins it looks like all the other raisins are moving away
from their perspective so it's not that we found out that everything is especially receding from
the earth for some reason but it's just how it appears due to the fact that this expansion is everywhere all at once
and so that's also why more distant things look like they have a greater recessional velocity
because if we think about these two pairs of galaxies say that the center one is the one we're looking at
so these two galaxies are close they're five centimeters apart these two galaxies are farther they're ten and say over
two seconds we're here which is very fast cooking bread we've made very special bread but say
over two seconds it's grown this much so this has gone from five centimeters to ten centimeters which is a change of
five centimeters for two seconds which means that it's 2.5 centimeters per second that's the
velocity of this one according to the one in the middle but to the one on the right that was
more distant initially it's gone from 10 centimeters to 20 centimeters which means it changed
10 centimeters over those same two seconds which means that that's a difference of um five
centimeters per second not 2.5 so to the raisin in the middle it looks like this one is moving away
with a greater velocity even though it's doing the same exact thing the one to the left did so when we look at this plot it says
things that are farther away will look like they're moving away faster for this reason even though it's not a true velocity but
just a consequence of the space in between growing so this raisin bread is a lot like
the universe which is very important i think that this analogy is very elucidating
so moving on in our story of dark energy because it's far from done um in some ways it's only getting
started is in 1998 which is many many years later
two teams realized that the universe is expanding as we already knew
but it's expanding at an accelerating rate which essentially means if you think about the raisin bread
the bread wouldn't be rising at a constant rate but as time goes on it would rise faster and faster
and this was a crazy discovery and we can talk about why why is this a crazy discovery um is that
intuitive is intuitive that the universe's expansion should be speeding up and for reasons that we talked about no
it's not quite intuitive because the universe is holding a bunch of mass which even if the universe is growing the mass
is exerting that force that's pulling it in on itself that isaac newton had mentioned so if it's expanding that energy should
be decreasing over time and yielding to the mass that's in the center so how is it speeding up it's it's
gaining energy from nowhere it seems to violate the conservation of energy which is essentially the idea
that you can't create new energy you can turn mass into energy but you can't create new energy out of nothing
so this seems to violate that principle because it's getting faster over time for virtually no reason um so this was a
very crazy discovery and as i said 1998 that's incredibly recent
so essentially what people thought before once they finally admitted that einstein and his colleagues were wrong
and okay we have to accept the universe is expanding um they were comfortable for a few years but then they got thrown a curveball
again um by discovering that it's accelerating so what people thought before is that the universe is expanding
but it's slowing down because the energy should be decreasing and the matter should be pulling the universe in on itself what people know
now is that it's expanding but it's speeding up for some unknown reason so
something is fighting against gravity but we don't know what it is and that is dubbed dark
energy um dark energy is whatever is propelling the universe to fight gravity in this way um in dark
energy especially since it's so incredibly young is even more poorly understood we have less of an idea of
what it may be but that's why it's so exciting to learn about now because you can try
to get involved in the process to figuring out what's going on the leading theory is that it is a
property of empty space or an intrinsic energy of space which essentially means that space itself has energy and the reason
it would increase is because we talked about how space is introducing more space so if space has an intrinsic energy say
you have this much space it'll have a certain amount of intrinsic energy but this intrinsic energy will
drive it to get bigger but now that it's gotten bigger there's more space so there's more space
expanding stuff so it's like a feedback loop space wants to make itself expand
so the more space there is the more it's going to expand so that's the general idea for why it is
speeding up but the mechanism is to exactly what this energy of space is and how it's going on is what people are
trying to figure out and specifically as i mentioned quite a
bit ago when i said that 74 of the universe is dark energy that's actually currently
very intention there were even recent discoveries like every day actually um probably that
are influencing this tension it seems like it's not going away and the tension that i'm talking about is that there are two methods for
discovering dark energy that i won't get into in detail the pictures um show a little bit of the detail but
essentially you can think of it as there's one way of calculating how much dark energy is contributing to this
expansion where you look at the nearer part of the universe and you use that to make your
calculations and then there's another way where you look at the very distant universe to make your calculations
and they should give you the same value um energy of space should be sort of a constant thing
throughout space even though space is speeding up the thing that's making it speed up shouldn't change um but what we're
finding is that when we use these two methods of measuring how much dark energy there is and how strong it is
basically that's what these numbers represent we're finding very different values that are not overlapping
um one group using the nearby method is finding that dark energy is 74
of the universe and the other is finding that it's about 67 and they may sound close enough to you
um but in cosmology this is actually a really big problem
um at a recent conference about this someone that was someone that is essential to
the study of dark energy um adam rice i believe his first name is adam
um said basically that we are in a crisis um about the value of dark energy and
how much is contributing to the universe but as i've said before to cosmologists that's incredibly exciting
because that means that we can all try our best to reconcile it and figure it out and if
anyone wants me to go into details about these two methods and how they differ um i can do that if anyone asks
um so this is another picture representing actually the three different values these two are more long-standing and
there's a clear distinction between one of them is a mirror method one of them is a far method
but there are three values now that are competing which makes it even more of a mess which is even more exciting but there is
a third method that has came out extremely recently i think this lines up to 2019
for their most recent measurement where they say that it's 70 which is right square in the middle of these two
and the error bars don't overlap um so that creates another problem
so this is dark energy right now um we're in the thick of it we're definitely in the beginning stages
of understanding um what this is and again as there was with dark matter there are people who
think maybe we just need new physics maybe there's not an intrinsic energy of space but maybe we're just fundamentally
misunderstanding something other people think that maybe one or two of these methods
are just prone to having errors in their data and maybe that's why we're
getting wrong measurements some people think that dark energy maybe isn't constant
over the universe but maybe as time goes on that energy of space gets stronger gets weaker and it can
change um all of these are not necessarily off the table because this is so incredibly new
and ongoing so essentially that's dark matter which has a lot more
questions than has answers even compared to dark matter but we arrive at this model
which is the lambda cdm model and lambda stands for essentially dark
energy and cdm stands for cold dark matter and matter which is our regular matter that we're
made of and this little piece of text this symbol represents what we
feel like we currently know um which is very subject to change um always is
but this is essentially generally um an overview of the theory of modern
cosmology in terms of where we stand um and i thought i would add this picture again just to wrap it all up
but any question wow yes there are some questions uh
cameron gillis is asking is there a theory that uh for the effect of dark matter
uh or that the effect of dark matter is the effect of the folded fabric of space oh jeez that's beyond my pay
grade um i think that there are definitely a lot of theories like that um that are more fringe theories but
um i mostly have studied the mainstream ones so okay i couldn't speak to the validity of that but i think it's definitely worth
looking into because everything in cosmology sounds ridiculous if you think about it too much so it's at least worth
worth a shot at studying okay there's another question
what is the latest theories on white holes on white holes um from my understanding
those are the corollary to black holes i think where people think that there's an
immense amount of like matter um receding from them um i don't know anything about it
personally but i would say just from my intuition that um i feel like we would have observed
that unless people think that they're in other dimensions which actually is something i think that comes up as an
issue when we're talking about things like dark matter and dark energy but yeah i don't personally know about
that okay uh gabriel wants to know can general relativity actually explain dark matter
um so i'm not really sure i think that the particles that are
being theorized as very likely candidates for dark matter um fit within um what we understand of
quantum mechanics but there is tension between relativity and quantum mechanics that
is um still sort of an issue that wasn't brought up here but i think
that also sort of is integrated into this whole pantheon of issues um but that's
something that i don't know much about either i gotta remember all these so i can look them up myself right
uh harold locke wants to know what amount of dark matter has been collected so far in these underground
underground collection bins so we haven't actually found something yet that we can definitively say is a
dark matter particle um we have had very recent developments in a an observatory in italy i can't remember
its name but i think in 2019 there was something published from them where they thought they found an axion
which would be a good candidate for a dark matter particle but those things have to go under rigorous review and for a very long time
and other people have to discover them so i believe there's at least one thing on the table if it hasn't yet been
disproven that may be one single dark matter particle that we found but we'll have to wait until people at
other observatories maybe see something similar or their data is finalized but as of yet we have nothing that we can point at and
say we've found you dark matter but when it happens it'll be super exciting so
chris larson says i've heard the train horn analogy several times now this is the first time i understand it
in relation to light and measuring the distance of stars that's great a lot of people uh uh
are you know they really love the way that you have explained some pretty complicated
concepts here so that's great yeah let's see
um
people are saying that you're making their minds expand here
that's great that's the goal let's see
these questions they're making excellent presentation i mean people love your presentation thank you very much um uh let's see
you know some if some random sophomore can learn all this you guys can too
well you're not some random sophomore uh christy white says she did an excellent
job of explaining this even i understood her so that's great
i i think it's wonderful you know the uh really a mark of intelligence is the
ability to explain something that's very complicated uh so that almost
anyone can understand and um uh that that is also a mark that you
that you have a good understanding yourself so thank you thank you rachel um
just following that line of thought i need to read you just a couple comments that are here
this is making sense something must be wrong [Laughter]
this is great rachel is very clear i enjoyed it clearly everybody has
enjoyed your talks thank you so much we will have to have you come back again
it's been a lot of fun very educational for all of us i'm sure
and i greatly appreciate you being here as everybody else does of course it's what i love to do so
oh well yeah you can tell enthusiasm always has a way of showing up when somebody really enjoys what they're
doing so thank you very much really appreciate you for giving me there is a
last question i guess is there an expanding universe theory that considers a
4d mobius strip fabric oh beyond my favorite can't even [Laughter]
i gotta go find a cool youtube video explaining that no problem you've done great thank you
what i would like to do now unless somebody else has comments right now i'll move to the questions unless somebody here has
comments all right i am going to give the answers to the
questions that uh i asked at the very beginning
and uh our winner will be j manifold for the first question m30 it's a
globular cluster in magnitude 6.9 it will
rise in the east just as dawn starts to break so catching that before daylight is the
challenge object in the messier marathon cassini it is cassini a that is the
large crater that sits a little off-center in the crater of cassini
and dusty haskins has answered that question
the last big bird question to me here is it is the aftermath of supernova
1987a and that irregular blob in the center might be heated from an enshrouded
neutron star the bright ring surrounding it consists of material
that a star released 20 000 years earlier the supernova shark shock wave is
lighting the ring i think that's amazing i saw that and that just amazed me the correct
answer was given by liam plybon so thank you all
for answering that i would like to let you know thank you for attending
but our next astronomical league live event will be on march 12th at 7 pm and dr barbara harris
will be our speaker at that time all right yeah so we hope to see you then and i
will quit sharing my screen there um i don't think you were sharing your
screen there we go thank you scott and uh if there's
what did i miss you weren't sharing you weren't sharing your speech oh that wasn't very good was it
somebody next i thought it was just like something seeing something invisible or something no do you want me to run through those
again are we good i think we're good tell me i will
i will there's another comment here from claude plymate who uh
a professional astronomer that's worked at uh kitt peak and also at the big bear solar
observatory and he says excellent talk thorough and very clearly presented so
thank you that's a big compliment so yeah thank you um does anybody else have any
comments here before we wrap up uh they they're saying awesome thank you
so much terry you know thank you scott thank you for doing this thanks everybody for attending rachel
fantastic job thank you so much don very much appreciate your talk too
and everybody else here on the league i really appreciate you being here and all of our visitors that are also
sitting here listening so thank you all very much please catch up with us on march 12th
with dr barbara harris thank you very much and we'll see you next time
okay thank you take care bye
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wow you