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Margaret Geller is best known for her work on the large scale structure of the Universe, helping us understand the large clusters, super clusters and cosmic filaments that matter clumps into.
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This episode is sponsored by: Swinburne Astronomy Online, 8th Light
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Transcription services provided by: GMR Transcription
Fraser Cain: Astronomy Cast episode 359, Margaret Geller. Welcome to Astronomy Cast, weekly facts-based journey through the cosmos. We’ll help you understand only what we know but how we know what we know. My name is Fraser Cain; the publisher of the university and with me is Dr. Pamela Gay, a professor at Southern Illinois University, Edwardsville and a director of CosmoQuest. We’ve been waiting.
Pamela Gay: I’m doing well. How are you doing, Fraser?
Fraser Cain: Good. I don’t know if I’ve ever mentioned this in the show but actually say professor at Southern Illinois University, Edwardsville is actually really hard.
Pamela Gay: It is. It really is.
Fraser Cain: To rattle that off, I have to slow down and I have to really choose my words very carefully and I can often flub it up. That’s where I will flub it up so I encourage everyone in the audience to just go ahead and say that seven times, Southern Illinois University, Edwardsville.
Pamela Gay: So if you want to know the full glory that I have to write into grants, it’s a professor in the Center for Science Technology Engineering and Mathematics Research Education and Outreach at Southern Illinois University, Edwardsville.
Fraser Cain: And the director of CosmoQuest.
Pamela Gay: Yes and at line wraps.
Fraser Cain: As a visiting professor?
Pamela Gay: No, as an assistant professor, assistant research professor is my full title.
Fraser Cain: Right. There you go. That’s even more line wraps. Cool, so before we get into this week’s show which is where we continue our focus on some of the most influential female astronomers, we would like to talk about a place where a person could perhaps pick up some schwag.
Pamela Gay: Yes. So as we enter the holiday season, we know that hopefully many of you out there have people in your lives that you love and you want to give awesomeness to and we have our own small corner of awesomeness on the internet and that is our store on Spreadshirt. The URL is astrogear.spreadshirt.com and we have a variety of mugs and t-shirts and sweatshirts and pretty much everything is customizable so that you can get it in the color, the size, everything that you want.
I’ve put forward my favorite girl cut and boy cut stuff and we have everything from a shirt that says explore, planet Pluto classic that is a parody shirt of the Coke classic logo to Astronomy Cast apparel to CosmoQuest awesomeness so please get some good Astronomy Cast nerdery to give to all those you love.
Fraser Cain: Fantastic. All right so on to this week’s topic.
All right, Pamela, we’ve got something special this week. We’ve got a new sponsor for Astronomy Cast and that is casper.com and they make mattresses. The cool thing with this is they sent us both individually mattresses to test out. Did you get yours?
Pamela Gay: I did and it was this crazy situation where I kind of forgot to tell my husband there was a mattress coming and he opens the front door and there’s a box that is just big enough for a human to fit in which is actually really tiny when you think about mattresses.
Fraser Cain: Well, you got like the twin-sized one or the smaller one, right? Yeah, and so I got the king-sized one and what’s amazing is I don’t think the box for the king-sized one was any bigger than the one that you had and there was like, I don’t know what laws of physics they broke to get this mattress in there but it was folded and rolled and so they gave you this special knife to cut the thing open and then it’s sort of inflated and you have a full on king-sized mattress and it was super comfortable.
We actually have gotten rid of the old mattress and we’re using the Casper mattress. It’s a terrific mattress so we, now having tested it out, I really glad we got them as a sponsor for Astronomy Cast.
Pamela Gay: I have to say the same thing. I got an extra-large twin one to put on the day bed where I do a lot of reading and fussing around on my iPad and all that sort of stuff and initially I just kind of put it on top of the old mattress and that lasted for about two days and the old mattress sort of got ditched and it’s awesome, it’s squishy but firm-ish and it doesn’t have the problems our Tempur-Pedic mattress has of making you super hot.
Fraser Cain: Yeah, exactly. You’re not up against this kind of foam that gets you really hot. No, it’s great. So the good folks at Casper, in addition to sponsoring Astronomy Cast are providing you with a discount on your own mattress so if you go to casper.com slash astro and then use the promo code astro, you can get $50.00 off your own mattress and they will ship it to you, I think anywhere in the United States.
Pamela Gay: This means that you can fall asleep listening to Fraser and I while sleeping on the exact same mattress that Fraser and I are not on the same mattress but the same kind of mattress that we have.
Fraser Cain: So go to casper.com slash astro. Use the promo code astro and you’ll save $50.00 on your own mattress.
Margaret Geller is best known for her work on the large scale structure of the university, helping us understand the large cluster, super clusters in cosmic filaments that matter clumps into and before we dig into this, I actually just posted something on Twitter that was so cool. It was like what the universe would look like if you could see dark matter and talk about filaments, just like neurons and like spongy thread connected together and this is the kind of stuff that Margaret Geller helped us figure out. So who was Margaret Geller?
Pamela Gay: So Margaret Geller is a female astronomer who is at the Harvard Smithsonian Center for Astro Physics. She got her PhD from Princeton and was actually one of the first women to do that and she has spent her career basically trying to figure out what is the environment in which galaxies reside and how do we trace out this larger scale structure of all of the galaxies that turns out aren’t quite so evenly distributed as we might have once thought.
Fraser Cain: So before Margaret Geller did her work, what did astronomers think the universe was structured like?
Pamela Gay: Well, we were getting the idea that there are clusters and super clusters but we kind of thought that there was this variety of different-sized structures but perhaps it was just kind of evenly distributed kind of like a fractal pattern of well, here’s small galaxies, here’s big galaxies, here’s groups of galaxies but we weren’t entirely sure and it actually took Margaret Geller and a variety of colleagues across many different years working on a variety of different surveys to finally start to realize that our universe is kind of shaped like Swiss cheese and the first diagram to really, well, to be unintentionally punny to bring this to light was the Geller Huchra diagram that came out and it showed the red shifts of galaxies on the axis going out from the center and then it traced an arc across the sky.
So what happened was John Huchra who was a great observational astronomer went to the telescope and using spectroscopy measured the rate at which galaxies are moving away from us here on earth and took into account the motion of the solar system, the motion of the galaxy, all of that and figured out how these different velocities related more or less to the position of these different galaxies.
Putting that together got this really neat diagram that actually has what looks like a stick figure dude kind of centered in the bottom of it and that stick figure dude is the coma cluster and it turns out that the motions of the galaxies within the cluster stretch out the cluster into a stripy bit and all of the rest of the structures slowly are in this first diagram just tracing out this lace of structure. Over the decades, they’ve taken more and more red shift measurements and pushed out the distance and the density of galaxies that they’ve measured and discovered the great wall, a large wall-like structure of galaxies, found more and more clusters and found more and more voids and realized it’s not a random distribution. It’s actually very purposeful distribution of structures.
Fraser Cain: It’s interesting the way you’ve chosen these people. I’m sure you did this on purpose but how sort of the dark matter [inaudible][00:10:12] with the stuff we talked about last week, more about sort of the, some of these large structures that created tractor things like that and it’s the same concept about how you’ve got these large scale structures which are all kind of related. The dark matter is the thing that’s sort of organizing and harnessing them together into these shapes and the expansion of the universe is creating these voids and filaments, right?
Pamela Gay: What’s been really interesting is with each of these different women whose work we’ve been choosing to highlight, these are women who made discoveries that required long term year through year careful consolidating of multiple results to aggregate an understanding that couldn’t come quick and dirty. It required long term detailed analysis and they did that needed long term work to build a completely unexpected understanding of our universe.
So they essentially saw hints of well, I was trying to study this one thing but realized there’s something deeper going on here and they did the research necessary in Vera Rubin’s case to figure out there is dark matter affecting the rotation rates of galaxies. With Margaret Geller to realize that galaxies are clumped and there’s voids and to figure out what that physically means and how this all relates back to the Big Bang, these are long term studies that are just, literally changed how we see our universe. There’s no other way to put it.
Fraser Cain: Right so let’s talk a little bit about Margaret Geller then. So where did she go to school? Where did she sort of get her training?
Pamela Gay: So she as I said, got her PhD from Princeton, she got in 1975 in physics. She was one of the first women to do that. Previously she had gone to the University of California at Berkeley again getting a degree in physics and from there she went on to the Harvard Smithsonian Center for Astrophysics and in 1980, she got appointed to Harvard Colleges’ astronomy department in a tenured track position.
She was in that position for three years and then she actually left the tenure track and while she’s never come right out and said it, a lot of people have said for her that the reason she left was because of the amount of harassment and backstabbing and snarky comments that she had to face day after day after day while she was at Harvard and when you’re told enough times you’ll never get tenure because you’re a girl, well, it’s easier to say I’m just gonna step back and be a research professor, a research scientist.
If you’re on a tenure track and denied tenure, you’re given one year to find a new job. You’re out. You’re gone but if you instead step back and fall into a research track which is what she did through the Harvard Smithsonian Center for Astrophysics, you have a position as long as you can find funding for yourself. Now the weird thing about this from Margaret Geller is here’s a woman who literally changed how we view the structure of the universe. She has gone on to publish lots of papers, over 125 and I stopped counting.
She has received the MacArthur Genius Grant. She has become a member of the National Academy of Arts and Sciences, a fellow at the American Physical Society, award after awards. She’s one of the top in her field and she actually has appointment of a full professorship or she did until she resigned in ’99. She was appointed a full professor without tenure at Harvard and she was offered a extremely important well-funded name chair. This is one of those things that you only get when the university basically says hey, you’re awesome, we’re gonna keep you. It was the Meloncrod Chair.
But they said we’ll give it to you but we’re not gonna give you tenure, we just won’t and she was the only person to ever be offered that chair and not given tenure. She actually neither said yes nor no to that position. She dug her heels in and said tenure.
Fraser Cain: And why not if not?
Pamela Gay: So that offer came in ’97. In ’99, it became clear that tenure wasn’t coming and so she resigned her professorship at Harvard to strictly be a senior research scientist at the Harvard Smithsonian Center for Astrophysics.
Fraser Cain: Right. From the reporting side, a ton of what we do at the university comes out of the Harvard CFA. We get probably a couple of stories a week are coming out of Harvard’s Center for Astrophysics. There’s tons of really breaking news coming out of there.
Pamela Gay: It’s a complicated situation because Harvard is known as kind of being a cesspool for gender harassment. When I was there, I know of a woman in physics who was asked to document how many hours a day she spent with her newborn because there were complaints that she was actually using the maternity leave to get ahead on her research which was considered unfair so she had to document that she was spending enough hours with the child for it to be considered maternity leave instead of maternity leave or just extra time.
Fraser Cain: Right, research.
Pamela Gay: Yeah.
Fraser Cain: Right.
Pamela Gay: Some of the things that you experience and are told, it just gets exhausting and I can fully understand having experienced things like this at many different places why Margaret made the decision she did and I have the utmost respect for her basically saying you’re offering me this amazing opportunity but you’re putting strongs on it and I’m not going to roll over and accept this prize with your strings. I want this prize only if you give it to me the same way you’ve given it to everyone else.
Fraser Cain: Right. So I guess is that where she currently is then?
Pamela Gay: Yes. She’s currently at the Harvard Smithsonian Center for Astrophysics. This makes her a civil servant. It means that her funding comes predominantly from grant research that like me she’s in jeopardy of, and this is why I feel for it is I have the very similar position at my university being in a research center which means no matter how good I do, the second I don’t have enough grant money, I’m out of a job and this is something I’m currently facing.
Fraser Cain: Right. You’re always writing grants. You’re always looking to try and acquire money for the projects you need to work on because that’s what makes the whole machine run.
Pamela Gay: Right and universities really benefit from having research scientists. People in these types of positions, you bring in all of your own salary. You bring in money to fund people to work with you and then the university also takes a percentage off the top. The percentage varies from institution to institution anywhere from a few tens of percents to actually requiring you to bring in more than twice the amount of money that you need and they’ll take half of it.
So the money that you bring in benefits the institution, allows it to build new buildings, hire support staff. All of these different things keep the light on, the heat going, and fund students and fund computers for other people and do all of these other things that keep the institution going while the institution makes no promise to you and at any moment, you can be out the door. For her to say you know, this is where I’m gonna stick unless you give me tenure, that’s a brave thing because a name chair like the Meloncrod chair, it does come with money. It does come with a certain amount of security that helps and she said no, I’ll take my lot as a research scientist.
Fraser Cain: So what else has she worked on? She worked on obviously this original work back in the ’80s of large scale structure of the universe. You mentioned a great wall. What is that exactly?
Pamela Gay: So if you look in one direction across the sky in what’s called the first center for astrophysics red shift strip, that’s where you see the stick figure dude but when you look at the stick figure dude, you see coming off of his arms this kind of wall of galaxies and as you continue to look at fainter and fainter galaxies, that wall gets thicker and thicker and as you go to higher red shifts, you realize that wall has nothing on one that appears at a more distant red shift.
So our stick figure dude, he’s at a red shift that translates to moving at 10,000 kilometers per second. The great wall is out at 10,000 kilometers per second and spreads out all the way from 16 hours to about nine hours of right ascension across the sky and it’s kind of awesome and we’ll include pictures.
Fraser Cain: Right. We always talk in terms of like arc minutes, arc seconds. We’re talking about arc hours here, right?
Pamela Gay: Arc hours, yeah.
Fraser Cain: So that’s a big chunk of the sky.
Pamela Gay: Yeah and it starts to fade off at about nine hours and what’s really cool looking at it is at about 16 hours, there’s this long spiky bit coming off of it and that long spiky bit is another galaxy cluster where the galaxies are moving so rapidly in the cluster that they spread out in this long finger. These are sometimes called the fingers of god in the red shift space.
Fraser Cain: You know, are these part of the Virgo super cluster or way farther away?
Pamela Gay: So looking at this, the stick figure guy that’s the coma cluster and one of the other fingers of god in this diagram is actually the Virgo cluster so we’re picking up a couple of different mass of clusters of galaxies and this wall which just extends all the way through this particular strip, so the one that really makes the wall start to stand out is the Center for Astrophysics two survey and it’s the first six slices put together that allows us all to stand out and with the picture –
Fraser Cain: I think through Geller’s biography and she also is the co-discoverer of hypervelocity stars.
Pamela Gay: Right. That is something because I don’t do that field of research, I totally forgot about. So hypervelocity stars are stars that get ejected through a variety of different interactions or supernova explosions and they’re basically these runaway objects that you can measure across a lifetime how they move across the sky and that’s kind of cool.
Fraser Cain: Yeah, absolutely like you can have like a three body interaction or you can have as you said the supernova going off and detonating and the blast kicking a star out of the entire galaxy which is pretty crazy. Cool, okay so what else should we know about Margaret Geller?
Pamela Gay: So she took things from just doing the initial maps of the one dimensional or two-dimensional rather slices through the universe to building complete 3D maps and her work led to some of the very first renderings that people saw on TV shows and in planetariums. She did an 8-minute video in 1989 called Where the Galaxies Are that created a voyage through this large scale structure and actually was awarded the CINE Gold Eagle Award. She went on to do a 40-minute film called So Many Galaxies, So Little Time that won awards for its graphic renderings from the I Tripoli in Zagreb and it was on display at the National Science Museum so our National Air and Space Museum.
So here you have a woman who does amazing science who is doing hard complicated work detailing red shifts, figuring out spectras, all observational work and then you have to figure out what theories match your observations to try and explain everything. She’s working to make sure her results get published in the top peer review journals and make sure they reach out to the public through accessible videos and easy scripts. She’s given lectures all over the world and she’s even on the National Public Radio here in the United States, their list of best commencement speeches ever. So she’s a woman who can communicate.
Fraser Cain: Right and that’s really, really important. I think that was Carl Sagan’s magic and a lot of people like, now we have Neil de Grasse Tyson but I think where Neil is really great at explaining things, you know, Margaret Geller did the research, understood the implications and then helped get them simulated in a way that regular folk, the public could wrap their heads around. I guess it’s a really good recent event like this is like what happened with interstellar right where Kip Thorne helped lead this simulation of the black hole, Gargantua whatever in interstellar, with such a level of precision that it both looked beautiful and had some useful scientific understanding for research so that’s the magic.
If you could take these what are just numbers, I mean they’re just right ascension, declination, you know, red shift, whatever, what kinds of composition of the galaxies and turn that into a 3D rendering that shows you what our local neighborhood looks like. That really helps put things in perspective. So, I mean that’s some of my favorite – when people do that, I’m really excited.
Pamela Gay: One of the things is actually articulates indirectly is one of the reasons often given for why she doesn’t have tenure is well, she’s cranky. She’s difficult. She’s grouchy. She doesn’t work well with others but then you look at the body of her work and she’s had collaborations that lasted decades. She’s worked with people from a whole variety of different backgrounds and when you see the range in working with top scientists and top creatives in projects in the private sector and she’s given multiple talks at the Chocotal Institute which is an indigenous people’s institution, clearly this is someone who does know how to collaborate and the irascible professor put it very well in a blog post where he says I can imagine that something like the following discussion must have gone on in these hallowed halls of Harvard University when the issue of tenure for Geller was being discussed.
Professor Y, and we’ve already promoted her to full professor. Shouldn’t we make it official by granting her tenure? Professor Z, she’s exactly one of the old boys. I don’t know if she would fit in over at the faculty club and besides, there’s just no evidence that she’s able to walk on water. This is a woman who’s done amazing things but –
Fraser Cain: If she can’t walk on water, no tenure.
Pamela Gay: Exactly.
Fraser Cain: Yeah, so then you know, I mean she’s still an active astronomer right now, still a researcher. Her career is not over so what is she working on like right now?
Pamela Gay: She’s part of the Sloan Digital Sky Survey Team. So when you see this amazing new renderings that allow you to fly all the way out to the cosmic microwave background radiation, she’s one of the people in that collaboration that is taking our understanding that started with this one narrow slice that showed coma cluster stick figure dude to now doing this massive wedge through the universe that is allowing us to test models that show how our galaxies’ structure has evolved from the cosmic microwave background to today. That’s just awesome.
Fraser Cain: She combines a large deep complete red shifts survey with a weak lensing map for the deep lens survey so I guess this is dark matter lensing distribution matched with red shift survey.
Pamela Gay: This is adding the dark matter component to the luminous matter component so that you can start to see how is it that light matter does and in some cases doesn’t trace out the dark matter by looking at how the dark matter leaves evidence of itself by distorting light passing through it.
Fraser Cain: There was some great research that just came out just the last couple of weeks about how quasars line up strangely within these filaments of dark matter.
Pamela Gay: That sort of makes sense if you think about it in terms of quasars trace out galaxies that are undergoing massive star formation in some cases undergoing collisions, all sorts of activities that happen more in the early universe. The dark matter is the places that were, it was in its highest density, it pulled the luminous matter in so luminous matter flowed in to this dark matter scaffolding, started forming structures, these structures interacted. The structures were the first galaxies and those galaxies were interacting in these filaments of dark matter that allowed all of this material to be drawn together.
Fraser Cain: So one thing I just did here, I just put her name into astro ph into archive.org, the astrophysics and for her name and she’s in 118 papers and that’s just one for astro ph.
Pamela Gay: That’s actually low so the number –
Fraser Cain: That’s not all the papers. This is just the ones that came out since astro ph was keeping track of them.
Pamela Gay: Right, exactly and yeah.
Fraser Cain: That like four years maybe is what I think it’s about.
Pamela Gay: The number that I found was in 2001. She had 127 published articles since 1982 and then there’s been like another hundred since then and yeah.
Fraser Cain: So just hundreds so that is a very prolific –
Pamela Gay: Yes.
Fraser Cain: Cool. All right, well, thanks a lot, Pamela.
Pamela Gay: Thank you.
Fraser Cain: Thanks for listening to Astronomy Cast, a nonprofit resource provided by Astrosphere New Media Association, Fraser Cain, and Dr. Pamela Gay. You can find show notes and transcripts for every episode at Astronomy Cast.com. You can email us at info@astronomycast.com. Tweet us at Astronomy Cast. Like us on Facebook or circle us on Google Plus. We record our show live on Google Plus every Monday at 12:00p.m. PST, 3:00p.m. EST or 20:00 GMT. If you miss the live event, you can always catch up over at CosmoQuest.org.
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