Ep. 473: Remembering the Best Space Science of 2017

2017 was a crazy year for, well, you know. But, it was a great year for space science, a kilonova, extrasolar planets, reusable rockets and more. Let’s look back at the year that was and remember our favorite space science.
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This episode is sponsored by: Barkbox

Show Notes

Gravitational Waves
Icy Worlds
More exoplanets
Cassini’s finale
Trappist-1 system
The Great American Eclipse
Blue Origin’s rockets and ships!


Transcription services provided by: GMR Transcription

Fraser: Astronomy Cast Episode 473: Remembering the Best Space Science of 2017.
Welcome to Astronomy Cast, our weekly facts-based journey through the cosmos, where we help you understand not only what we know, but how we know what we know. My name is Fraser Cain. I’m the publisher of Universe Today. With me is Dr. Pamela Gay, the Director of Technology and Citizen Science at the Astronomical Society of the Pacific and the Director of CosmoQuest. Hey, Pamela. How you doing?
Pamela: I’m doing well. How are you doing, Fraser?
Fraser: Good. Happy New Year!
Pamela: Happy New Year to you! We are between the American Geophysical Union Conference and the American Astronomical Society Conference in this weird, in between time of year where all of us are focused on trying to catch up on our inboxes. How are you doing?
Fraser: Fine. I’m all caught up on my inboxes. It was nasty. I gotta say. I hit the ground running Monday this week, Tuesday this week – I guess that was in the New Year, Tuesday – and tried to catch up everything as best I could and I definitely just finished digging myself out from the pile.
Pamela: And Monday is when the yearly firehose of press releases will begin with the AAS meeting – which I will actually be at and reporting information out from. So, everyone stay tuned for information from that. Then, in February, I’m actually gonna go to a computer science conference in Europe. So, all you folks over in Europe who are into computer science consider going to the European Testing Conference and perhaps I can see you there and it’ll be great to have another side of STEM to report out on.
Fraser: Right on. Alright. 2017 was a crazy year for … well, you know. But it was a great year for space science; kilanova, extrasolar planets, reusable rockets, and more. Let’s look back at the year that was and remember our favorite space science. We’re just gonna take turns. How do you want to do this? Pull randomly?
I refuse to have a number associated with this. There are no constraints on me. I am gonna range far and wide, talk about the stuff that I loved and – if stuff pops into my head and I’m remembering it – it was part of the greatest. This is how I’m gonna be going.
Pamela: I am completely, completely down with that.
Fraser: Okay.
Pamela: So, what was your favorite because I’m sure you have strong opinions?
Fraser: Oh, do you want to go straight to the favorite?
Pamela: Yes.
Fraser: Well, it’s gotta be the kilanova then.
Pamela: Yes.
Fraser: The big, big, big, big, big space news of the year had to be the discovery of these two colliding neutron stars that generated this enormous explosion, generated both gravitational waves and visible light in the electromagnetic spectrum. What that did was it was just this gigantic boon because they finally could see the objects that were colliding to create the gravitational waves and then use that to confirm all kinds of things. It was amazing.
Pamela: And it wasn’t like they resolved the individual neutron stars, but they resolved everything about the collision of those two neutron stars and what was really amazing is it’s estimated that one in five professional research astronomers around the world was employed in this one discovery. They used up the whole electromagnetic spectrum. It’s gone. It was all used up and gravity … and gravity.
Fraser: Yeah, and the part that I love – and as I was reporting on the story and I was sort of trying to wrap my head around the timing – it was that there was this flurry of particles that was detected by one of the … or it was a flurry of radiation–
Pamela: Gamma rays.
Fraser: Yeah, that came from one of the NASA satellites and then that matched up perfectly with the gravitational waves that were being generated. But, in fact, it was like a few seconds after and what it was was that – as the neutron stars were spiraling in towards each other – they were generating these gravitational waves and then moments after they hit and then they went silent, but then they generated the electromagnetic waves and you got like Einstein’s prediction that gravity moves at the speed of light completely confirmed. Done. There’s no question now. It’s solved.
So, it was an absolutely amazing, amazing discovery and kind of ahead of its time. I don’t think anybody was expecting to see this kind of an outcome from these detections this early. It was a really lucky discovery.
Pamela: I think the only observational astronomers who were sad were the people who look at neutrinos because they’re the only ones who didn’t see this event pretty much. The neutrino people, they were out of luck, but everyone else had new data that we could work together to tell this fabulous story. But that wasn’t the only great story coming out of the year. So, I know, for me, it was basically the year of the weird stuff we can’t explain – which is the stuff that I get super excited about.
So, Tabby’s Star continued to be a complete mystery. The black streaks on Mars continued to be a “We’re going to argue about it.” It was just all these little things of “And we still don’t fully understand this.” Planetary was where we kept getting these things where it now looks like Enceladus has a subsurface ocean where we caught landslides from the Rosetta Mission of the comet they were observing and then saw the emission afterwards. Yeah, lots of pretty pictures we now have to explain.
Fraser: Well, I mean some showed up just right at the end of the year. So, a lot of people didn’t get a chance to talk about this in some of their year-end roundups. For example, on Mars, it now really seems to be that the evidence that those landslides that we thought were caused by water might merely be caused by sand.
Pamela: Or even weirder than that, have you seen the image where you can clearly see defined something rolled down the slope?
Fraser: No, no, like a rock. I’ve seen a couple boulders have gone down the hill.
Pamela: Yeah. So, in at least one case, it looks like it was dry ice basically cleaving off the top of the rim and then rolling down creating these streaks. It’s just kind of wild to look at.
Fraser: And I would say one of the biggest discoveries of the year was you know you mentioned what they’d found on Enceladus, but even more interesting than that was they found hydrogen gas venting out of the vents on Enceladus – which is food for bacteria here on Earth – and that’s just an amazing, amazing discovery that you’ve got essentially the perfect environment for happy bacteria deep below on the oceans on Enceladus. This is leading.
I’ve actually got a new video that’s gonna come out today. Hopefully, by the time people listen to this, they will have seen this, but there is a revolution. There are thousands of times more of these icy worlds like Enceladus out there and the evidence is just accumulating and accumulating that these are the places to go.
Pamela: And what has been so amazing about this year is planetary science and exoplanetary science are really coming into their own where we’re seeing new discovery after new discovery after new discovery from the sweetest spacecraft that we have out there, from the newly released images of Earth and the moon that were taken by OSIRIS-Rex that really show how empty space is.
Fraser: I love that picture.
Pamela: And then, there are the essentially watercolor pictures of Jupiter coming back from JunoCam. We have Maven helping us understand the Martian atmosphere and how it went from having a thick atmosphere to a depressing atmosphere that keeps foiling parachutes on heavy-weight objects. It’s amazing.
Fraser: Yeah. We’re gonna use the word amazing about a million times this episode and I apologize in advance. Maybe Chad can cut some of them out. I don’t know. But one of the big sad stories – the bittersweet one – is that we lost Cassini. Now, we knew this was coming.
We knew this day was gonna be happening, but right on schedule Cassini made sort of a last series of fly-bys, we had some course corrections, passed closer and closer right through in between the rings and the planet, did some final observations of some of the moons, and then smashed into the upper atmosphere of Saturn and is gone forever to protect the icy worlds from infection from our filthy Earth life.
Pamela: It is no more. That is true and on its way out, it got high risk, high resolution images of Saturn’s rings that allowed us to really get a sense of what is the structure of the rings? How are these formed? What are the defects? It’s awesome to see all of the little gravitational – eddies isn’t quite the right word – but it seems to perhaps be the best word to use. Yeah, it’s super cool.
Fraser: Super cool. Not amazing, super cool.
Pamela: No.
Fraser: Part of the bitter sweetness I think of this is that Cassini is the last flagship spacecraft that we have operating now in the solar system. I mean there was the Pioneers and the Voyagers. There was Galileo and Cassini. Just these gigantic missions like school bus sized spacecraft with a tremendous suite of instruments designed to just – not to necessarily answer a specific question – although they did have some of those goals – but really with the capability to analyze and study anything that it finds in the environment.
Cassini marks the end of these flagship missions and what’s coming next are these smaller, more purpose-built, more direct question-answer type spacecraft. Even things like Curiosity crawling around on the surface of Mars is a much more scaled down mission than something like Cassini. We’re gonna see James Webb in 2019, but nothing else is really gonna be we hope – please launch – but there’s nothing else out there that’s really of that scale … not Juno, not nothing.
Pamela: WFIRST sort of. WFIRST is going to be another more slightly versatile telescope that’s designed to find dark energy basically and it has the potential to do more, but you’re right. what we’re looking at is a huge sum of money has been sunk into Curiosity, is being sunk into the 2020 Rover, has been sunk into the Atacama Large Millimeter Array, has been sunk into the James Webb Space Telescope and what’s left – after paying for all of that and for sustaining all of our existing missions that are out there and all of the ground-based facilities – doesn’t really leave room for any new flagship missions.
But we still have so many of our great observatories. Chandra’s still turning out great data. Fermi is still turning out great data. Hubble is still turning out great data – although a very large telescope is nipping at its heels to be competitive on a regular basis. So, it’s a new and different time. There are sadnesses. Kepler isn’t working as planned, but there are also so many successes and Europe is coming to the rescue with some amazing missions. Gaia, what they’re doing with their CCD continues to amaze me and then there’s just the VLT and they’re starting to build their overwhelmingly large telescope.
Fraser: Although this is bordering into predictions for 2018, we’re just working on a story right now about how Gaia is being used potentially to observe some of the longest wavelength gravitational waves moving through star fields – the ones generated by the super massive black holes that can’t be seen by any of the other observatories – that it could see these dimmings and brightenings as these big, long gravitational waves move through stars which–
Pamela: Is crazy talk.
Fraser: Yeah, it’s crazy. I love this idea so we’re working on a story about this. Now, you mentioned briefly extrasolar planets and there was one of the most fascinating extrasolar planet discoveries that have been made so far and this is the TRAPPIST-1 system and that was earlier this year.
Pamela: We finally reached the point where we’ve been observing exoplanets for enough years with the right suites of instruments to be able to tease out multiple eclipses from these Earth-sized planets – which are so much harder to observe – and we’re finding them and we’ve started finding things between one and several Earth masses that have atmospheres, that are at the correct distance from their stars to have potentially liquid water on their surface.
Now, this doesn’t mean that can and do support live. Venus theoretically – totally capable of supporting life – reality would kill you in the most amazing and painful ways. Death by fire versus death by Venus is a close, “I’m not quite sure which is worse.”
Fraser: Yeah, you’re oven roasted on Venus and then acid bathed.
Pamela: With acid, yeah. It’s like, “Burn me and crush me and pour sulfuric acid into it.” So, yeah, on Earth death by fire definitely the worst. In the solar system, I’m not sure which is worse.
Fraser: But you know the discovery of the TRAPPIST-1 system and just this because Kepler was damaged, a lot of the observations are going after these red dwarf worlds and the potential planetary systems that could be around it. The TRAPPIST-1 is discovered by a different instrument, but we got seven Earth-sized worlds in the habitable zone of their red dwarf star, which is just an astonishing number of planets, although they probably suck. They’re probably no good to … and, in fact, as we mentioned now only AC worlds matter. So, let’s not even bother looking for habitable – a planet’s inhabitable zone – anymore.
Pamela: I think more worlds do matter but – while we’re discussing extrasolar worlds – I really have to call attention to the every horribly named JG1132B, which is this Venus-Earth atmosphere-ish world that is somewhere between one and two Earth masses, probably around 1.6. It’s a little bit bigger in radius than Earth and it’s a world that we found an atmosphere on that would probably kill you. But we’re finding worlds with atmospheres now.
Fraser: Yeah, and this is gonna be – now looking into the future – I mean there’s gonna be a whole group of instruments, telescopes, capabilities that are gonna be able to analyze the atmospheres of these worlds and, of course, looking for bio signatures, which we’ve talked about quite a bit.
Pamela: This week’s episode of Astronomy Cast is brought to you by BarkBox. I have a big old Australian shepherd. His name is Eddie and he’s about 50 pounds of pure energy and every month, I’m able to get him to contain all that wiggling energy into a small, vibrating bundle of sitting dog. He sits ready to explode when he sees that BarkBox.
I let him do his own unboxing each month – which you might have seen me posting up on Twitter – and almost always the first thing he does is he pulls out one of the two squishy toys that they have that are made of great materials that are sized appropriately for your weight dog and then he digs in looking for the big old treat that he knows is in there somewhere and he sometimes buries them.
What’s kind of awesome is right now I get to learn just how much he loves and values his BarkBox because he’s been going in the yard and finding those buried treats – a bully stick, a pig’s ear – and he’s bringing them inside to keep them safe in the winter weather. All of these treats are made here in the United States or in Canada. Everything is made of ingredients that you can recognize and my dog loves them – loves them, loves them – and remembers where he put them so he can find them and keep enjoying them for days to come.
Make your dog this happy too. Go to BarkBox.com/Astronomy and when you subscribe for six or 12 months, you’ll get a free extra month. I hope your dog is a happy BarkBox-loving dog.
Fraser: So, let’s shift gears then and talk about an astronomical event that we both … Well, I experienced. You mostly experienced.
Pamela: I got burned by it quite literally. In August, there was the great North American solar eclipse and I don’t think this was one of the top science discovery events of the year, but it was definitely the largest “everyone pays attention to it” science event of the year where we had a path of totality that spanned from Oregon on the West Coast out through the Carolinas on the East Coast. It’s estimated that a couple hundred million people probably saw some or all of the eclipse and we were part of it.
Fraser: Yeah. So, we went down to your nearby hometown, St. Louis, with 100 of our closest friends – listeners to Astronomy Cast – and then we all hopped in buses and we went down to Carbondale, which was at the point of greatest eclipse, and you went off to go help … You were what, with the Weather Channel?
Pamela: I was with the Weather Channel and the irony was I’d been saying all weekend, “I’m abandoning all of you guys during totality. You don’t want to be with me because wherever I am there will be a small cloud directly over my head.” I did not realize how true that statement was going to be.
Fraser: You called it, yeah.
Pamela: Yeah.
Fraser: For those of us who were out there, we got a fairly small cloud – I mean relatively speaking. It was just for us that came right over the region that we were all on and so we had this beautiful view of the sun and the eclipse as it was moving towards totality and then – about five minutes before it hit totality – this cloud moved in. For us, who were far away from you and limited by your damage, so we missed the beginning of the totality and then the skies cleared for the last maybe 45 seconds.
So, I just got to see the corona and then things … So, I got to see the diamonds on the edge and then the eclipse was over. So, I got to see something. I got the highlight of it, but I didn’t get to see the full eclipse experience and you got even less.
Pamela: Yeah. I saw the beginning of the diamond ring at the beginning and then – while on national television with people in my ear reminding me that my mic was hot – I saw a cloud, just a cloud, along with Jim Cantore and the two of us are destined to attract clouds, which is much more useful in his profession than mine. The cloud went away just in time to see the end of the diamond ring at the end of the eclipse.
Fraser: Right, yeah. But I’m hooked. Paul Sutter and I are trying to figure out how we’re gonna be able to do the 2019 eclipse down in Chile and I’m sure we’re gonna do another event for the 2024 one when it crosses Carbondale again, but also goes through a bunch of other places that could be even more sunnier like through Texas and stuff. So, I think we’re gonna be able to find a good view for the 2024 one.
Pamela: And we are going to do more Astronomy Cast events was one of the things that came out of this. Next year is the IAU in Vienna – which makes trying to figure out when to do something a little bit more challenging – but there are going to be more Astronomy Cast events and, of course, you’re partnered up with Paul Matt Sutter on a bunch of stuff.
Fraser: Yup. Off to Iceland in a month to go chase auroras. But, for me, 2017 I was able to cross one of mine off my bucket list, which was to see an amazing aurora. I put the aurora alert app on my phone and it had been nagging me on a regular basis to go out and see if I could see some auroras. So, we gathered up the family and went out to this beach that has nice, good, dark skies and a great view out to the north and it was just this green glow down on the horizon and then suddenly, the whole thing just kind of exploded with colors.
It must have taken up a third of the hemisphere when it’s high – almost at the zenith – and it was just amazing flickering fountains. It was everything I could have hoped for. So, I’ve got to say it’s amazing to see. I’ve said amazing 42 times. If you haven’t already, go seen an aurora. Do what you can to get yourself somewhere where auroras happen and take part in that because it’s been a really good year for auroras so far.
Pamela: And that was the September coronal mass ejection of the sun, which was actually one of the largest coronal mass ejections on record.
Fraser: Yeah.
Pamela: So, our sun had to get in on being one of the top science stories of the year – both for what it did and for what the moon did to it in the case of the solar eclipse. We had a lot of different worlds getting on the list for the chemical signatures they showed, as you said Enceladus showed signs of having the chemicals for life. We also found that with Ceres – we haven’t brought up Ceres – this little rock currently being orbited by the Dawn spacecraft.
Actually, I think Dawn’s no longer there, but it’s been figured out that it also has the ingredients for life and so here there’s this really cool story being built up where Ceres was originally found to be a planet. It eventually got downgraded to being an asteroid. Pluto is not the only former planet. Then, as we’ve been working to study it more and more, we’ve realized it probably has a liquid ocean beneath the sea. It has organic molecules and here we go another place to possibly find life.
Fraser: Yeah. Now, we’ve talked about this being the year of space science, but we should talk briefly about some of the rocketry that happened this year as well and I think the big – although it wasn’t necessarily one story, although there were a couple that highlighted this – this was really the year that I think SpaceX cracked reusable rocketry. They must be up to 20 re-landed rockets that this point. They’ve reused a bunch of rockets.
Pamela: And they reused a capsule finally.
Fraser: Yeah, they’ve reused the Dragon capsule. The Falcon Heavy was moved to the Launchpad and then raised and then lowered right at the end of the year and hopefully is going to fly by the end of this month and sort of crank everything to the next level. But SpaceX wasn’t the only one. Blue Origins has been making a tremendous amount of progress on their plans as well.
They launched their New Shephard rocket with sort of a refurbished New Shepard, which is gonna be the vomit comet … the one for the tourists to fly up to and experience a little bit of weightlessness before coming back to Earth. But they also did a bunch of tests of their new rocket engine, which is probably gonna get used for United Launch Alliance’s new rocket, The Vulcan. So, you’re seeing this not just SpaceX running away with it, but a really serious competition from Blue Origins and some of the other companies as well. So, I think 2017 is gonna be a really interesting year to watch and see how this all progresses.
Pamela: I think you mean 2018 will be an interesting year.
Fraser: 2018, sorry. Yeah, yeah, yeah, not 2017. I just learned this today. Do you know that the Chinese are planning 40 rocket launches this year?
Pamela: You know it seems like this is somewhat fitting because 2017 was the 60th anniversary of Sputnik 1. So, we’re literally becoming a senior, well-matured field here and you know China – at the beginning of 2017 – going ahead and they have their second space lab up. They are successfully docking cargoes with it. You have India is starting to get in on the act with launching on one spacecraft 104 small CubeSats. So, now we have India in on the CubeSat side of things.
Fraser: Yeah. They’ve had a tremendously successful launch rate with a lot of their spacecraft. The MOM at Mars went a couple of years ago, but still a really terrific mission done for a fairly efficient budget.
Pamela: And so with China totally going it alone and showing that they’re completely competitive nowadays.
Fraser: Yup.
Pamela: With India becoming one of the nation’s able to be a workhorse launching satellites, it just seems like it’s a new, Golden Age kind of like back in the days where TWA and Pan Am were going head-to-head. Now, we’re going to have Blue Origin versus SpaceX versus all of these nations who aren’t the big boys who are coming in and playing fast and nimble the same way the commercial companies are.
Fraser: Yeah. We’re starting to run out of time, but I want to mention of course the first interstellar asteroid – maybe comet, maybe asteroid – Oumuamua. I’ve gotten very comfortable saying that. I don’t feel embarrassed now. But that was detected on this hyperbolic trajectory and is sort of the first confirmed object and it was super weird. It was a one to ten factor of its width to length so–
Pamela: Space natal.
Fraser: Yeah, it’s Rendezvous with Rama shape.
Pamela: Which is disturbing on every possible level, but there is zero indication that this is a spacecraft and they have looked.
Fraser: Yeah, they’ve looked … no luck. So, those are all of the big stories that I’ve got. Have you got anything else that you were watching this year?
Pamela: I think just it was the year of the pretty picture in a whole lot of ways and really everyone should go take a look at all the pretty pictures coming out of things – especially with Juno. Oh, my gosh that mission is creating all the pretty pictures. So, go look at that and go look at the final images that came from Cassini.
Fraser: And the fact that Juno’s camera is more of an afterthought – like it was there for the public, not really a super duper scientific instrument – and yet the pictures coming back from it are some of the most fascinating images that we’re seeing and I’m sure people are using it for science. So it’s a funny thing. Alright. Well, thanks, Pamela. We’ll see you next week.
Pamela: See you later.
Announcer: Thank you 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 astronomycast.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 YouTube every Friday at 1:30 p.m. Pacific, 4:30 p.m. Eastern, or 2030 GMT. If you missed the live event, you can always catch up over at CosmoQuest.org or on our YouTube page.
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[End of Audio]
Duration: 31 minutes

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