Last week we talked about the Neil Gerhels Swift Telescope, this week we’ll be talking about the man behind the mission. Gerhels was the principle investigator behind many missions, including Swift.
Show Notes
- Halloween and Elections
- Neil Gehrels Overview
- Career Highlights of Neil Gehrels
- Swift and Fermi Missions
- Personal and Legacy
Transcript
Human transcription provided by GMR Transcription
Fraser Cain [00:00:49] Astronomy Cast Episode 731. Neil Gehrels Welcome to Astronomy Cast our weekly facts based journey through the Cosmos to help you understand not only what we know, but how we know what we know. I’m Fraser Cain. I’m the publisher of University. With me, as always, is Dr. Pamela Gay, a senior scientist for the Planetary Science Institute and the director of Cosmic Quest. Hey, how am I doing?
Dr. Pamela Gay [00:01:10] I am doing well. It is October 21st, which means we are so close to Halloween and.
Fraser Cain [00:01:18] Make you happy.
Dr. Pamela Gay [00:01:19] I have all of the excite to do. You get triggered. You live at the end of like a snow or long driveway, you know?
Fraser Cain [00:01:27] We have no trick or treaters now. No. And now that I now the kids are out the door and and don’t do that kind of thing anymore. Used to be we would. One of us would stay home, handle the trick duties. The other one of us would take the kids to a denser place where there was a lot more trick or treating going on, and they could harvest more candy. But now, no, nobody comes our way. So. So Halloween is just like a it’s Halloween. Yeah.
Dr. Pamela Gay [00:01:56] That’s that’s. That’s tragic.
Fraser Cain [00:01:59] Well, it’s a phase in our lives.
Dr. Pamela Gay [00:02:01] I know. See, I live. We have no children, but I live in that neighborhood everyone goes to.
Fraser Cain [00:02:09] Right.
Dr. Pamela Gay [00:02:10] And the thing I am excited about is I. So. So Obama was my senator back when he was elected, so he had a lot of local support. And the year it was that presidential election, a lot of the kids would knock on the door and instead of trick or treat, they would say, vote for Obama, which was hilarious. And so I’m waiting to see what the kids say this year because the kids are okay. And your reminder, whatever democracy you live in, if you live in a democracy, you remember to vote and make sure you’re registered. If you’re in a country that that has to happen.
Fraser Cain [00:02:48] We just voted for our provincial government. Okay. So we’re we’re waiting for the results this week. We’ll find out whether which party won. So last week we talked about the Neil Gehrels Swift telescope. This week we’ll be talking about the man behind the mission Girls was the principal investigator behind many missions, NSA, including Swift. But that really is just the tip of the iceberg. And we’ll talk about it a second, but it’s time for a break.
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Fraser Cain [00:03:56] And we’re back. So I think before we begin this episode, we need to provide a correction for last week.
Dr. Pamela Gay [00:04:03] When we both made the exact same mistake. It was caught by Richard Drum, our audio editor. We both said Neil’s like Niels Bohr.
Fraser Cain [00:04:18] Yes.
Dr. Pamela Gay [00:04:19] And it’s Neil. Yeah. The American version of Dutch ancestry. His his father, Thomas Garrels, was a Dutch astronomer but came and worked in America. And Neil was raised in America. Right. It is no ass and right.
Fraser Cain [00:04:38] And we do it again. And I just want to apologize in advance. Clearly, the Niels Bohr is so is such a has worn a groove in our brains that that it’s our instinctual way to describe the word Neil. And apologies to all the needles out there and the needles.
Dr. Pamela Gay [00:04:57] This language is hard to decide.
Fraser Cain [00:05:03] So. Who was Neil Gehrels.
Dr. Pamela Gay [00:05:09] He was a American particle physicist focused on astronomy objects. And and his entire life was basically astroparticle physics. And what I love is this is your quintessential human being that was exposed to science his entire life and ended up in astronomy, even though he clearly, at one point considered hanging a left. So so growing up, like I said, his father was was an astronomer. He lived for a time at McDonald Observatory while his dad worked there. His dad ended up at the University of Arizona and in the department there. So he spent the remainder of his childhood growing up in Tucson. Like so many children of faculty, he went to the university his father worked at because that is how you get free tuition, right? So he did his undergraduate degree in music and physics at the University of Arizona. He was passionate about music, but somewhere along the lines decided, I’m going to go to graduate school. He got into Caltech, which is like one of the hardest programs to get into. And not only that, but like one of his to graduate advisors was Ed Stone, the person who did the Voyager missions forever and only passed away recently. And one of his graduate programs was actually calibrating the cosmic ray detector on Voyager. So you have this human who’s chasing down high energy particles and starting in planetary science for a multi-generational mission. And. Finishes that his very first postdoc took him to Goddard and he never left.
Fraser Cain [00:07:20] Right. Yeah. There’s a bunch of those lifers in Goddard who. Yeah. Work on. On mission after mission after after mission. So. So, like, I want to talk about some of his some of his early work. Like, I know he was instrumental, pardon the pun, in helping to develop balloon based astronomy.
Dr. Pamela Gay [00:07:38] That was a terrible pun.
Fraser Cain [00:07:40] I know. And then worked on with with other instruments in missions. So. So what do you want to start with with the kinds of work that he was that he was and I guess like specifically. Like what was his specialty, if you know, if he was going to join a mission, what was the thing that he was very good at?
Dr. Pamela Gay [00:07:59] So I think this is the thing that really got me trying to to understand what all to talk about in this episode is at the end of the day, he was a big picture thinker who had a strong understanding of instrumentation. And because of that, he could look at a science problem and say, This is how we should address it. This thing is capable of addressing it. We need to create this other thing to address this problem. And. One of the underlying subtext of everything I was reading was he had really good interpersonal skills, so he ended up leading things because he wouldn’t politically screw them up, which really most astronomers would because we don’t have those skills, right? Yeah.
Fraser Cain [00:08:56] Why would you listen to me? This is how we should do it. Yeah.
Dr. Pamela Gay [00:08:59] Yeah. He knew how not to do that. Right? Yeah. So here you have a human being with really good interpersonal skills, good political savvy who had the big picture thinking and ability to understand instrumentation, to look broadly at things. And he basically started from particles, moved on to gamma rays, which was a very new field of of big picture astronomy at that point. And then like ultimately before he passed away of pancreatic cancer, far too young, he was working on W first rate, which is not particles. It is not high energy.
Fraser Cain [00:09:51] That’s infrared. Yeah.
Dr. Pamela Gay [00:09:52] And and it was seeing that, that caused me to go backwards and be like, wait, how does this even happen? And the way it happens is you’re a big picture thinker who doesn’t tick off everyone around you and because of that can enable amazing things to occur.
Fraser Cain [00:10:08] Right.
Dr. Pamela Gay [00:10:09] He died way too young. We need people like this.
Fraser Cain [00:10:12] So w first it’s new name is Nancy Grace Roman. So. Right. So as you said and you make sense, like as a particle physicist, I’m thinking about how, you know, how can we perceive photons in various wavelengths, mostly gamma rays. They’re not visible down here, trapped under the atmosphere. You’ve got to go to space. But if you can fly high in a balloon now, you have a chance of being able to see gamma rays or to be able to see the particles that come off of gamma rays as they strike the earth’s atmosphere, cosmic rays, things like that. And so I think and then to sort of, as you say, take that through from gamma rays all the way through to infrared. I mean, I guess photons are photons.
Dr. Pamela Gay [00:11:02] And he also wandered into gravitational waves.
Fraser Cain [00:11:07] As they all do.
Dr. Pamela Gay [00:11:08] Yeah, yeah.
Fraser Cain [00:11:09] Yeah. That’s really interesting.
Dr. Pamela Gay [00:11:11] And so he he started with working on Voyager and and in the coolest, weirdest change of fate, I think I have seen in terms of what this instrument was designed for and what this instrument did. The cosmic ray instrument on Voyager, while it was a Jupiter, made a bunch of detections, which kind of makes sense. There’s a massive magnetic field there. And it turned out that what they were seeing were particles from the eruptions on Io’s volcanoes. Yeah. So his data looking at cosmic rays was, in this case, looking at massively accelerated particles from volcanoes.
Fraser Cain [00:11:55] Now, we didn’t know about the giant magnetic field around Jupiter and the trapped radiation until we flew through it. Right.
Dr. Pamela Gay [00:12:05] It was a a so the Voyager mission, I think we really need to revisit it now that we’re seeing more and more missions go out there so we can see. Yeah. Everyone talks about the voyage through the solar system and the whirlwind visit, everything but going back and focusing on just Jupiter versus Voyager because we didn’t know about the active volcanism, we didn’t know about just what kind of a magnetic field was waiting for us.
Fraser Cain [00:12:39] Yeah.
Dr. Pamela Gay [00:12:40] Geysers on Europa. Yeah. Yeah. But anyways, so. So working with Ed Stone as a graduate student, he did this cosmic ray detector for Voyager, which is what helped us figure out. Yes, they actually did eventually manage to leave and stay out of the solar system, which changes insides, which meant that they left the solar system more than once. He he detected these particles from volcanoes. Then the balloon observations that he did once he got to Goddard, he was part of Supernova 1987. A And I wish I had had time to reach out to Phil Plate and ask Phil, did he ever work with this person? Because Phil’s background was in gamma ray astronomy and he was at Goddard during all of this as well. So they must have known each other.
Fraser Cain [00:13:29] All right. We can talk about this some more, but it’s time for another break.
Dr. Pamela Gay [00:13:32] This show is sponsored by Betterhelp. I may be recording this October 28th, but it’s almost November almost. And better help would like all of us to remember that November is a time to reflect on the people in our lives that we’re grateful for. It should come as no surprise to any of you that I’m grateful to have a collaborator and friend like Frazer to work with week after week, literally across decades. He’s been there as a voice of sanity, coming to me from outside academia since I was a baby professor and I’m a better person for having him around. The one person I don’t think any of us think of when we’re asked to reflect on who we’re grateful for is ourselves. But at the end of the day, it is past us. That set us up for the life we now have, and the actions of current us are building a life for future us. There are a lot of times I’d like to reach back and bith past me for things like failing to write comments in code or clean up after myself when cooking. But I can also be grateful for things like the ice cream I know passed me got so that ice cream can keep me company on election night. If you have trouble reconciling gratitude and your relationship with yourself, therapy can help. As RuPaul says, if you can’t love yourself, how the heck are you going to love someone else? If you’re thinking of starting therapy, give Betterhelp a try. It’s entirely online and you can find a therapist who both matches your needs and your schedule, and you can change therapists at any time. Let the gratitude flow with better help. Visit betterhelp Dotcom slash astronomy today to get 10% off your first month. That’s better. Help. H e l p.com/astronomy.
Fraser Cain [00:15:31] Okay. And we’re back. Sorry.
Dr. Pamela Gay [00:15:33] It’s okay. I am clearly enthusiastic. I have. Yeah. Yeah.
Fraser Cain [00:15:38] Yeah.
Dr. Pamela Gay [00:15:39] So. So with the gamma ray work using balloons again, he just kept wandering through science with his instrument. So there are super number 1987 A There were blazars, which are galaxies with an active galactic nuclei that is sending jets out in an interesting way. I. He was looking at aluminum 26 decay mapping regions of nucleosynthesis in the galactic plane positron annihilation. So he’s now looking at how matter anti-matter are affecting each other. And it was balloon after balloon. And at a certain point, you need something better than a balloon. And this is where working with Compton plays such an important role. This was one of NASA’s great observatories, and it was what allowed us to finally understand with certainty what we had hoped would be true, which was gamma ray Bursts are evenly distributed around the entire sky. Now, he wasn’t with Compton from the very beginning, but he was there for a lot of it. And and working with Compton, he was there figuring out the distribution of these these gamma ray bursts and shoot, It isn’t just that you have to pay attention to their distribution spatially. You also have to look at their distribution in time and finding out that there’s multiple populations. One of his most cited papers is trying to come to terms with short gamma ray bursts. And where are they in galaxies, trying to figure out what are they from where they are.
Fraser Cain [00:17:31] Right. And we talked quite a lot about that with the Swift telescope and just how thanks to Swift, we got ever closer to learning that they are colliding compact objects. But you know stars.
Dr. Pamela Gay [00:17:45] And and so working as project scientist project scientist there is the project scientist and there are project scientists on a mission. So so from 91 to 2000, he was a project scientist on the mission. The project scientist after Donovan stepped down. Donovan was responsible for its development. And. And so here he was. Again, looking into the same stuff he was looking at with balloons. And from there it becomes a question of now we’re finding all these gamma ray bursts. You have someone with an instrument focused brain who thinks across multiple wavelengths particles, multi messenger astronomy was done by him before the phrase even existed, and he was then part of the development of Swift and Fermi from basically days zero.
Fraser Cain [00:18:46] Right? Yeah. So so let’s talk I mean, we talked a lot about the mission, but what role did he play in Swift?
Dr. Pamela Gay [00:18:59] He was he was the the principal investigator of the Swift mission, which meant that he was part of ushering it through politically to make sure it would actually happen. So so he was part of the team that went through, defined what instruments would be on board, defined what were the necessary functions of those. So what sensitivities do you need? What capabilities do you need? How does this thing need to be able to get from spotting something in gamma ray, zeroing in on x ray, zero in the in in optic and U.V. so that ultimately you can find any optical afterglow that may be present, observe them as quickly as possible so that we can finally figure out what these suckers are. So he’s again, going back to chasing what is necessary to understand these objects, doing multi wavelength astronomy. And then it took off.
Fraser Cain [00:20:04] So, yes. All right. We can talk about this some more, but it’s time for another break.
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Fraser Cain [00:20:42] And we’re back. So again, we put a lot of energy and time into the actual mission last week. So let’s let’s move on, because while Swift was operating Fermi, he worked on the Fermi telescope as well.
Dr. Pamela Gay [00:20:59] Yes. So so. And I just realized I misspoke. I meant to say he was the principal investigator for Swift. And I think I said project scientist. I meant to say principal investigator. He was he.
Fraser Cain [00:21:11] Was a project scientist for the Compton Gamma Ray Observatory.
Dr. Pamela Gay [00:21:14] Yes. But for Swift, he was the principal investigator. And I realized I said the same words twice.
Fraser Cain [00:21:19] And right around. Yes. But yeah. So he worked on Fermi.
Dr. Pamela Gay [00:21:23] Yes. So he worked on Fermi. He was the deputy project scientist there. So he was the number two person. On defining how Fermi is going to do science. He was with it when it was originally just called last. Yes. And and so here he’s starting to get into magnetometers. No, the the science he’s part of is ever expanding. And while he’s doing all of this is also when we’re starting to focus more and more from the decadal survey point of view on what the heck is dark energy. Dark energy was discovered in the late 90s. And there there is a lag between the we have discovered something now. Everyone makes sure we didn’t screw up. Okay. We did not screw up. Nobel Prizes have been issued. Now how do we figure out what this is? And there’s lead time needed. And as as we’re getting into the 2010 Decadal survey, there is this we have got to figure out dark energy aspect that came into play. And this is where W first, which which is built out of a 2.4m telescope that was donated essentially to NASA’s from the Air Force, as one does.
Fraser Cain [00:22:45] And I always sort of mentioned this story that the US Reconnaissance Office donated to NASA’s two Hubble class mirrors. Yeah, because they didn’t have any use for them because they didn’t meet their requirements anymore, that they weren’t good enough for the enormous reconnaissance telescopes that are pointing directly down at Earth that are bigger than the Hubble Space Telescope.
Dr. Pamela Gay [00:23:10] Yeah. So so with, with the snap dark energy mission proposal that he was on with with Saul Perlmutter, they were working on trying to figure out how do we figure out what this dark energy is. And that mission evolved into W first, which is going to be doing a lot more than just looking for dark energy. It’s now the Nancy Grace Roman telescope. It’s going to be looking at exoplanets. It’s going to be doing a lot of the looking at the mirror, infrared and optical far read that lines up with what I j had to because T is doing c of j w s t out doing the longer wavelengths and uv w first, which also has a smaller mirror 2.4 versus many, many more. And and so he ended up being project scientist and chairing the Science Coordination Group back in 2009 as they were defining this new observatory pushing to try and get a coronagraph on it or flying coordinated with it. And and he was part of of defining all of this up through 2017, where he was diagnosed in 2016 with pancreatic cancer. One of the worst things that he can get.
Fraser Cain [00:24:44] It’s almost always lethal. It goes it acts really quickly. Yeah, that sucks.
Dr. Pamela Gay [00:24:52] Yeah. So it it sucked. But what’s amazing looking back is in his I work with so many people that keep publishing papers into their 70s, keep mentoring like Parker, who we talked about last into their 80s and here he is. He passed away at 64. But look at this legacy from Voyager to Balloons to Swift to Fermi to Nancy Grace from. And when it finally lifts.
Fraser Cain [00:25:24] Off.
Dr. Pamela Gay [00:25:26] And all the while, he was apparently the person that when there was a random conference in a random part of the world, he was off hiking. He was off. He he had. Three ascents on the really difficult path path of El Capitan. That’s the thing that you see in Star Trek. Yeah, yeah, yeah, yeah.
Fraser Cain [00:25:52] He’s like a rock climber. That’s amazing.
Dr. Pamela Gay [00:25:54] He was an amazing rock climber. He was someone who loved to be outdoors, and he. He didn’t win every award, but he won a lot of awards. And I think in some ways, the even better legacy is how many papers he had that have been cited by just about everything. And what got me was, here’s a paper with the horribly boring title, Confidence Limits for Small Numbers of events and Astrophysical Data. This was a 1986 statistics paper that now has nearly 3000 citations. So he was the one who’s like, okay, someone has to figure out how to do these stats and I am going to do this. Single other paper appeared in the Astrophysical Journal. And there’s just all these other papers, like some that you would expect. The original paper on the swift gamma ray burst mission. Of course, it has over 5000 citations. But he also has one on the physical processes shaping gamma ray bursts. That is, again, over a thousand citations. And there’s so many things that are just around a thousand citations, 300, 500, 800 citations. Yes. His work is a foundation of so much other work. His leadership allowed so much other work.
Fraser Cain [00:27:39] Yeah. Yeah. And I mean, it’s such a tricky job to be in this environment where you’ve got the request from the scientists for the digital survey. Those seem to be turning to concrete missions, but you have to deal with the budgetary constraints, the changing administrations. And to see these missions through to completion and have them actually launch and be providing the science and actually have their ongoing maintenance budget, like there is so much leadership that’s required across that process.
Dr. Pamela Gay [00:28:07] And these weren’t easy missions. The world Fermi was glassed and got canceled. And I still have a strong memory of Phil Plait and I sitting next to each other. And Phil was associated with Glass and we were blogging our little brains out as the then administrator of Dasa was was talking during an ACA town hall and basically was like, all you astronomers belong at the children’s table because of all the work we had done. Canvasing and talking to Congress critters to get glassed refunded and finished and launched. And so here we had someone who was at Goddard at NASA Center, where what you can do is somewhat limited because government running a mission that then became so political.
Fraser Cain [00:29:04] I mean, to navigate that. Yeah. Yeah. Amazing. Well, that was really interesting. And, you know, sounds like the perfect person to have a mission named after them. Thank you, Pamela.
Dr. Pamela Gay [00:29:18] And thank you, Fraser. And thank you to all the folks out there that support us through Patreon. We can’t read all your names, but we are going to read some of the names for the $10 a month people. We get through the entire list once per month. This week the names are Andrew Stephenson, Astro Bob, Astro Sets. Brenda. Brian Cagle. Brian Kelby. Bruce. Amazon. Daniel Loosely. David Diaz. Trina. Don Manders. Elliot Walker. Father Prox. Glenn McDavid. Greg Davies. Gregory Singleton. Hal McKinney. Jeff Collins. Jeff Wilson. Jeremy Kerwin. Joanne Maldi. Joe Holstein. John Saiz. Jonathan Powell. Jordan Turner. J.P. Sullivan. Columbus. Author of Love Science. Christiane Magers Holt Conception. Flanker Larry Salt Lee Harbaugh and Lou Zeeland Mark Steven Rusnak. Mike Heisey. Noll. Noah Albertson. Powell. Al Hayden. Robbie The Dog with the Dot. Robert Cordova. Robert Plasma Scone. Scott Bieber. Shawn Matt. Steven White The Air Major. The Big Squish Squash. The Long Sand Person. Thomas Gazette A Time Lord IRA Tricorder Will Hamilton and Zero Chill. And I’m now lightheaded from seeing all of your now I love how many there are.
Fraser Cain [00:30:34] Yeah really high balled through it. That’s awesome. Thanks Pamela. And we’ll see you all next week.
Dr. Pamela Gay [00:30:39] Bye bye. Astronomy cast is a joint product of Universe today and the Planetary Science Institute. Astronomy Cast is released under a Creative Commons attribution license. So love it. Share it and remix it. But please credit it to our hosts, Fraser Cain and Dr. Pamela Gay. You can get more information on today’s show topic on our website, Astronomy Cars.com. This episode was brought to you thanks to our generous patrons on Patriot. If you want to help keep the show going, please consider joining our community at patriot.com/astronomy cast. Not only do you help us pay our producers a fair wage, you will also get special access to content right in your inbox and invites to online events. We are so grateful to all of you who have joined our Patreon community already. Anyways, keep looking up. This has been astronomy cast.
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