StarTalk Radio - Rosetta and Comet 67P, with Natalie Starkey - StarTalk All-Stars

Episode Date: September 13, 2016

On 9/30/16, the Rosetta spacecraft will purposefully join its Philae lander and crash into Comet 67P. Before then, StarTalk All-Stars host Natalie Starkey, co-host Chuck Nice and Rosetta Mission Project Scientist Matt Taylor review what we’ve learned. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

This is StarTalk. Welcome to StarTalk. I am Dr. Natalie Starkey and this is StarTalk All-Stars. Today I'm going to be your All-Star host and joining me as a co-host I have comedian Chuck Nice. Hey Natalie. Well, Natalie. Natalie. Nice to see you. Good to see you too. Thank you for coming in. Well, Natalie. Natalie. Nice to see you. Good to see you too. Thank you for coming in. Always a pleasure.

So today the plan is to field some fan questions about our topic today in the Cosmic Queries. We're going to be looking at the topic of the Rosetta mission. Yes. Really exciting. It very much is an exciting mission. Very close to my heart. I'm sure it is. Because it's kind of what I've been doing for my research the last few years.

And so I'm excited to talk about Rosetta. Very excited. And I'm also more excited to introduce our guest today, joining us via Skype. And it is Dr. Matt Taylor. Dr. Matt Taylor. Yes. Welcome, Matt. Thank you for having me.

That's all right. Now, Matt, you are the project scientist for the European Space Agency Rosetta mission. This is quite an exciting title. I wish I had your job, but you are really, really busy. So I don't envy you for the amount of travel and talks you're currently doing. But it's so good to have you here. It's my pleasure. It's my pleasure.

It is a bit hectic at the moment, surely. So explain to us, there's a lot going on, right? So we've had the Rosetta mission launched, I mean, over 10 years ago now, right? And it's been traveling to this comet. It was traveling to a comet for all of this time. It had to catch up with this comet, get onto the same orbit, which is no small matter in itself. Right.

And then in 2014, it actually caught up with the comet, went into orbit around it. First time ever we've done this. Yes. And then not only that, a couple of months later, landed as spacecraft on a comet, which was just the best thing ever. And, you know, first time we've ever done this. It was successful, a soft landing.

There was a little bit of a bumpy ride until it came to rest. But, you know, it's done science. It did its first science sequence as planned. And since then, the little lander, little fillet lander, as it's called, is asleep. It's gone to sleep. It's gone to sleep. Matt, what's happened to it? Is that the scientist's way of saying that it's now on a farm with your grandmother?

What do you mean when you say it's gone to sleep? What's happening? Don't you guys try to tell me something? The problem with it, it's like Schrodinger's lander. We can't really tell. Ah, okay. I got you. We can't come up to the comet and kick it

to see if it's still alive. It's highly unlikely to be able to function anymore at the moment due to power limitations, due to the fact that it's moving away from the sun. Right. But, yeah, as Natalie said, we carried out the first science sequence. We carried out the main part of the science. It did what it was supposed to do, which was to go into hibernation. which was to go into hibernation. And it's just because it did this extra little leap across the comet,

but it was put into a situation or a location where it took a bit longer to come out of hibernation than originally planned. I think you guys were just being cheeky, though, because you were like, we want to land on a comet, but hey, wait a minute, we're going to land three times, not once. We're going to just do it all in one go. Funny enough, one of the original lander proposals uh i think this is by uh helmut rosenbaum the kind of main father of the lander mission itself was to have a comet hopper that was jumping around that would go to one place and

then go somewhere else and it was as if that ethos was somehow impregnated into the lander that it wasn't happy enough to be in one place he wanted to go somewhere else it was like i like that proposal let's do that i'm gonna do it anyway but it's kind of crazy because you know comets have like so little gravity these things are relatively small compared to you know one of the planets so it's just really lucky that it didn't on one of these bounces bounce completely off and just go yeah right it would because it that could have been a scenario where it bounced off and it would have been lost forever at that point, right? Exactly.

There'd be no way of getting it. It had no power itself, the lander, so it couldn't have got itself back. It couldn't have gone back. Yeah, so that would have been bad. It clipped one of the kind of clips or whatever you want to call some of the features on the surface of the comet, and I think without that, it had lost a little bit more momentum. And without that little that, it had lost a little bit more momentum.

And without that little clip that it made, it may have had a little bit too much momentum on one of the bounces and ended up going over the edge and that was it. It would have been lost. So, luck was there. We were lucky. We got it.

We got some science, which I'd love to discuss if we've got time today. But, you know, it's still there. But it woke up, right? The lander did wake up again in, was it July last year or something? Yeah, it was June it's still there. But it woke up, right? The lander did wake up again in, was it July last year or something? Yeah, it was June-July time period,

but we never got a full accurate signal lock with it. There were some issues. We never really got in talking terms with it properly. Right. But it's really, it's important to know, I have to know that this isn't the only part of the mission. This gets forgotten that the rosetta mission is more than the 60 hours of data taken that we had with philae that we were and the majority of the science is

being done by the orbiter and remains being done by the orbiter says the physicist i have to point out because all the physics experiments are on the orbiter okay i'm a geologist so i'm like right i want to be on the you want to be on the comet and pulling up samples and getting something back and readings. He is exactly right. The orbiter is still functioning. All right. So, Matt, with respect to the orbiter, what kind of data are you looking to receive as it orbits this comet on its journey? Is it just primarily looking at the comet or is it surveying the uh the you know what's around the

comet and where the comet is going are both of those things happening or one of those things or what it's it's doing both rosetta itself the key aspect was that unlike any other mission we've done before to a comet uh we were going to stay with the comet so as natalie said before we rendezvoused and we got in the same orbit as the comet. And we've been doing that for over two years now. So we got in step with the comet and we've seen how the comet has evolved in time. As it gets closer to the sun, it was becoming more and more active, throwing more material off. We've been monitoring the comet and we've been observing the comet, both the nucleus and the outer atmosphere, and how that actually, in addition, how that interacts with the outer atmosphere of the sun as well so the whole you know the whole nine yards that's what

we've been looking at we've really been uh looking the whole thing about the rosetta mission is to study this comet as in-depth as possible and with the lander we get the ground truth of these measurements but with the orbiter we get the global view and we match those together that was the key aspect of this we do the majority of the science with the orbiter, we get the global view and we match those together. That was the key aspect of this. We do the majority of the science with the orbiter. But the land was there. Philae was there to get on the ground and give us the ground truth to really dig in and let scientists like Natalie, who like to, you know, dig and scrape in and sniff and taste things.

It's good. She's always rolling around and playing in the mud. But Matt, what I wanted to just mention is the end of the mission, because it's going to be a really sad time for all of us. I imagine more so for the guys that are really heavily involved on the mission side. But the end is coming. It's this year. The end is near.

The end is very near. Oh my goodness. And there are some really crazy plans of how this mission is going to end. And it involves essentially crashing this orbiter that's doing all this amazing science, all these very expensive instruments on board, crashing this thing into the comet. OK, now that sounds, Matt, very much like when I was a kid, I would build a giant Lego castle and then kick it down. Why? Why? Why is that the end of the mission? What is going on with you guys? I'm like, you know, I've always wanted to break stuff, really expensive things. No, the problem we have is the comet is moving away through Keplerian motion, it's moving away from the sun. Now the spacecraft is orbiting around or is in the same orbit.

That's moving away from the sun as well, losing the capability of generating power. So we'll get to a situation where we would have to put it into hibernation. We had to do that before because it moved so far away from the sun anyway. And because of the orbit the spacecraft is now in with the comet, it would freeze. We're also running out of fuel we'll have no fuel left soon and the best thing to do was to end the mission in around September October time actually the reason for that is we get to a time where the solar energy is reducing but also we go into a conjunction with the

Sun so the signal that we're getting from the spacecraft is very minimal at that time period so we kind of thought the end of September would be a good time to close the mission off. Now we could have just switched the mission off or do something more extravagant. And the more extravagant thing has been to carry out a controlled impact with a comet. A controlled impact, sorry, not a crash. Yes, exactly. You know, that's what I tried to tell my insurance company about my last controlled impact with another car. I love this idea because it means on the way down, the instruments are still going to be on

and they're going to get tons of information as they go down because this will be the closest we've ever been with the orbiter, obviously, having not crashed it into the comet yet. They've done some amazing maths to work out. Sorry, math. I'm in the States now. I forget math. Yeah, we've done some very clever math to work out how to orbit around this thing, because it's not quite as haven't really got enough gravity for an orbiter to just orbit. It's not going to be in a gravitational tractor pull.

A little bit, but it's been in powered flight a lot of the time. So it's you don't want to get too close but this comet is also active so it's got material streaming off the surface so you don't want to get that orbiter too close and be hit by dust right particles coming so this is like our best chance to get close get some really detailed images of the surface i think you know one pixel is that going to be a meter or better than that um do we hope we get much i think once we get to within 10 kilometers we we get we go sub meter 50 centimeters 10 centimeters uh we're going to get very high resolution images once we get down to that level really yeah and and so as you take this uh as you capture these images and you're still in orbit around the comet as it's doing its controlled impact,

are you going to be surveying all parts of the comet, like kind of going around it and taking pictures like a radio camera? Will that be the case? That final, what we're calling the last words of Rosetta, is actually still being discussed, is being calculated. Because although this comet is very low density and has a weak gravitational attraction, it still has gravity. So the orbiter actually is now in a bound orbit. We're about, I think it's 26 by 20 kilometer orbit.

We will go closer and closer and closer. We'll get below 10 kilometers. And once we get to below 10 kilometers, things get very complicated because of this duck like structure. And so we have a very weird gravitational potential once we get down to that. So we'll have to put it in a special orbit and really be careful how we control the spacecraft around that time and we will feel perturbations of that gravity and we will be continuing to try and do as many measurements as possible once we get close by now those final words as we you know we're talking about the last day of rosetta what we do there is still being discussed still being fine-tuned we believe it

will be some kind of a resting maneuver from a close pericenter orbit. So we'll have like maybe an elliptic orbit that goes within about one kilometer maybe, the surface maybe even lower, depending again on what we're doing in September. And then we'll inject towards the comet and just set ourselves up to be able to take data as close as possible.

Now, the priority will be the imager, but also the mass spectrometer to sniff everything as close as possible. We'll have other instruments operating, but when we start getting to low power during that period, we really have to say, right, these are the priority instruments. Getting those images, getting the high-resolution images, and also the high-resolution spectra from this mass spectrometer that's sitting in the gas. And that excites me. That does excite me.

I love mass spectrometers. And is there any anticipation as to what the comet will smell like? Because I'm hoping jasmine. It is far from nice. We already know how horrible this thing smells. There's alcohol on it. It's like a kind of Friday night in a bar area in any city in the U.S. or Britain or wherever. Are you telling me this comet will smell like a drunken fart?

Yeah, pretty much. Yeah. It's probably not a good place to be. It smells like Jersey. I can say that. I live there. We should probably move on to some of these fan questions. Because we've been nattering on about this.

No, that was a ton of fun. And I want to get some questions. Yeah, we should get some questions, without a doubt. But I'm so happy that we had that conversation. Yeah. Because now I know that basically we spent a billion dollars to find out that a comet smells like a fart. Quite frankly, that was worth my tax dollars. All right, guys, let us go to our cosmic queries where we have taken questions from all over the Internet and every different incarnation where StarTalk exists.

And I am going to start off with Greg Fisher from Facebook. And Greg says this. Are we planning any other missions to any other comets? Is there any specific interest in landing on one of the asteroids in between Mars and Jupiter or in the Oort cloud? Oh, this is a great question. That is a very good question, Greg. Very good question. Thank you. This is, oh, I love this subject.

There's so much to talk about, but I'll try and I'll keep it fairly short. So we're not planning any missions to comets at the moment, unfortunately, but we are planning some missions to some asteroids. Now, these are not in the asteroid belt between Mars and Jupiter because it's quite a long way to go. What we do is we wait for these asteroids to be knocked out of the asteroid belt and join us in the inner solar system. So these become near-Earth asteroids. So now let me just, I'm not infringing on your question, Greg, but how do we know when an asteroid is going to get knocked out of the asteroid belt? We don't know when, but we I don't think we can tell when anyway, but I'm probably not the right person to ask.

But we know when they have been knocked out and we know we can trace the orbit so we can we can observe them in space. And we have a whole list of near-Earth asteroids and we have a list of those that are on potentially Earth crossing orbits. These are the ones that we need to worry about. And we keep an eye on them. And we check, you know, that we need to just really define the orbit really carefully and work out. And gradually, these fall off the list, because most of them end up not, you know, as we work out a little bit more where they're going, they're not going to hit us. But there's a few that we want to go and visit with space missions, because they're kind of easy to get to, because they're already on a better orbit. We don't have to go and visit with space missions because they're kind of easy to get to because they're already on a better orbit we don't have to go as far um there's the nasa osiris rex mission

which is launching this year it should be launching this year and it's going to approach an asteroid called benu in 2018 i believe and it's going to be collecting samples to bring back to earth which is pretty much probably just the second time that's happened. The Japanese had a mission called Hayabusa that did this a couple years ago. I've worked on some of those samples, tiny little dust samples from this asteroid. But there's also the Hayabusa 2 mission, which is another Japanese one that's already been launched. And that is going to another asteroid, near Earth asteroid and collecting some hopefully collecting samples again. So we have a couple that we're going to.

Turns of getting to the Oort cloud, collecting samples, that's not going to happen. It's just so, so far away. Again, we need to wait for one of these comets to be knocked into the inner solar system for us to go to it, like we did with Rosetta and 67P. It came to us. So it makes it a lot easier. The Oort cloud is just an immense distance away that it would be, yeah, we'll never get there, I don't think.

Not in our lifetimes. All right. Oh, well, Greg, that is a great, great question. Because this is a cool question. Do you know what, Chuck? We actually need to take a break. Okay, well, then I'm not going to read this then. Can we come back?

Can you save it until after the break? No, that's it. You've ruined the show, Gary. We've ruined it now. Let's go. All right. Okay, so we are going to take a short break but we'll be right back with star talk all stars welcome back to star talk all stars i am natalie starkey and i still have here with me chuck nice who's going to be asking me some more cosmic queries and i've got matt taylor on hand from the European Space Agency to help answer some of the questions if I can't answer them.

Absolutely. So let's jump right back into our cosmic queries. And let's go to Josefina Akiaro. Same again. Yes, Akiaro in Waltham, Massachusetts. Okay. And Josefina wants to know this. She says, first of all,

I'm a huge fan of Rosetta Mission and StarTalk. Aren't we all? There you go. That just means you're smart, Josefina. That's all that means. I'm a chemist by trade, and I was wondering what the implications would be of a Rosetta finding that, A, only left-handed amino acids were found on Comet 67P, or B, only right-handed amino acids, or C, a racemic mixture, i.e. equal amounts of both.

Now, before you and Matt go totally geek boner crazy on this question, you're going to have to tell us what all of that means. What it all means. I have no idea what Josefina is talking about, but it's an opportunity for me to learn something. Okay, so we'll kick off with the fact that we want to look for organic material in space. And I think this is kind of what the question is getting at. Are we looking for organic material in this comet?

Well, yes, we are. There's quite a few instruments on the orbiter and lander that are looking for these features and trying to detect carbon molecules. Now, in terms of looking for anything more advanced than that, if we're talking DNA, I don't think there's anything that can look for that. But if we come back a step before we get to DNA, we've got amino acids, which form from carbon molecules. And these are what we would refer to as the basic building blocks for life. We kind of need these to get life started, we think. And our bodies contain loads of amino acids, and we found amino acids in space before.

We found them in asteroids, meteorites that land on the surface as pieces of asteroids. We found lots and lots of amino acids. So we know that the building blocks are out there. Now with Rosetta, we're not looking for these specifically, but there are a couple of instruments that are trying to detect carbon compounds. Now I'm going going to pass over to matt because he can now tell us a little bit about what some of those instruments have found because it's quite recent research that's just come out oh we're getting breaking news here yep it is definitely so yeah matt there's a couple of instruments on the lander that have found some interesting stuff related

to the organic material yeah um both ptolemy so Open University Instrument also Cossack from uh from Germany were focusing on this specifically now from my knowledge and now remember I'm a plasma physicist so this is on the edge of my my comfort zone as it were I know that we did find a lot of organic material we could see that organic material this is carbon-based material the comet is really really dark it's it's very very black it reflects less than five percent of the sunlight that is uh input to it so that really tells you that we have this very carbon rich material on the surface and as i was saying before that you know this this ground level uh taste of the comet was what we needed from Philae, and that's what it got,

even with the bouncing across the surface of the comet. And we had samples, well, I'm trying to remember, actually, I think Cossack, if up is the top of the lander and down is the bottom of the lander, I think Cossack was pointing down and Ptolemy was pointing up. Exactly, yeah. And so they kind of got this fractional sample of the atmosphere in the near surface. So COSAC actually got the dust that was kicked up from the surface and really got some nice nitrogen and carbon-rich compounds. I think there were four compounds that have never been seen before,

and these are associated, I think, again, on the edge of my memory, with ribose, which is a sugar which then is, you know, again, a building block of, or can be connected to amino acids and DNA. So that was seen on the bottom with COSAC. And on the top, it was more of the coma material, more of the gaseous material that we were seeing in the atmosphere. And so we were able to see that and distinguish the different components from the lander.

Yeah. And the orbiter, we have Rosina that's got this fantastic array of instruments that do mass spectrometry and can sample material there. They've been looking at more of what we've had record or instances of seeing different, well, we were talking about it before, the methane, et cetera. And we hope to get some more information information on that soon that's all i'm we have an insight here this is exciting this is cool but it's great related to this okay well it's great because all the different instruments have done slightly different things um and

actually they don't all necessarily agree which is quite interesting so now what do you mean by that because that sounds uh that sounds very contradictory. Yeah, and it sounds worrisome. What do you mean that they don't all particularly agree? Well, basically, because they're measuring different things. As Matt was saying, the COSAC instrument is measuring the composition of basically the rock of the comet, because it's right at the surface. Whereas the Ptolemy, so it saw nitrogen compounds and things.

And then Ptolemy was measuring the gases around that. So it didn't actually measure any nitrogen. We don't really know why. Maybe the nitrogen wasn't kicked up high enough so that Ptolemy didn't get it into its mass spectrometer. But it measured lots of carbon dioxide. So we know there's a lot of carbon there. They agree on some things,

but then you've got Rosina, which is way outside of the comet, looking at the coma and everything outside of that. And that's, you know, obviously got different results, but I'm sure they'll be complementary it's just you're looking at different parts it's a common it's not that they don't agree it's that they're measuring different things okay and those things don't always just perfectly mesh no we have to put all of these little bits of data together and build up our picture of the comet because it's an active

system you know we've got to understand what it's doing as it goes towards the sun how it's getting heated up and how that's affecting the different molecules on on it okay so yeah but the one thing that we can say matt is that it's not broken so it's not like it's measuring different things because it's not working one thing that i recall is when i when i want to know is are you wasting my money? These are highly intricate instruments, but one has to recall, and I remember talking to a colleague of mine who was an undergraduate with me when I was in Liverpool University,

and he remembers mass spectrometers being as big as a room. And I think Natalie, you know, I remember talking to you at OU with these big machines. Yeah. Now, you can't fly something that big in space, so you have to miniaturize the instrument.

And I'm not saying the instrument, well, it has less capability. It's still a fantastic instrument, but you've miniaturized it. So it has a limited capability compared to something on Earth. So there's a limitation in what you can do. So you have to make assumptions on the observations that you're making. So the spectra have, you know, when you're looking at a mass spectrum, there are bumps and wiggles and lines everywhere that could be various different compounds that this thing's sniffing.

And you have to make assumptions based on your understanding in general of what they are. So it's really, you're doing the best you can with an instrument that's been packed in from a room-sized instrument to something as big or smaller than a shoebox. Yeah. Wow. It is amazing.

Because we need the instruments to be light because we've got to launch them into space. Exactly. And we need them to be relatively simple because we don't have a human to go up there and run it. There's no maintenance for this. If anything goes wrong, there's pretty much not anything you can do. You know, you pre-program sequences that it will run and the computer programs and it runs them. And if anything goes wrong,

there's just nothing you can do about it. So these things have got to be simple, but it doesn't mean they're actually simple. You know, they're still doing very complicated science. Yeah, it's physicist simple. Yeah, it is. Yeah, it's like, you know, you guys simple is like most people's, I just died of a stroke thinking about it.

And they also have another version of the instrument on the ground. So the scientists, you know, have been waiting 10 years for this to get to the comet. They've actually been able to perform lots of calibration experiments on their version that they've got maybe in a chamber that's kind of like comet conditions, so it's in a vacuum and stuff, and they can actually run sequences on it to test how that instrument's going to work in space. So that's important as well.

There's a lot of work that goes into it. And so, Matt, when you're running these calibrations, do you then take that and make an adjustment to the data that you receive from space and adjust it accordingly to the calibrations that you run here on earth? Well, yeah, that's what you do. And actually something that was done

based on the Rosetta measurements. So the Rosetta for this was for Rosina. They made measurements with their highly advanced instrument. And they were able to actually go back to data that was taken 30 years ago from the Halley mission, the Giotto mission at Halley, and readdress some of the spectra that were taken there with the instruments there and reanalyze them based on the measurements we have here. So in a kind of cross spacecraft mission calibration as well. So all of this data you can go across and cross compare and improve your measurements that is

fantastic yeah i mean that's really fascinating stuff well uh josephina uh let me just tell you that was an incredible question that you gave us because i mean who knew that we would get all of that out of this one question really fascinating stuff and and i learned some things there too that was really great well i feel like i'm one of the cosby kids look at that i learned something too ah you don't even realize okay all right i'm gonna stop that right now just to jump in there because the um josephina had asked about chirality that was one of the measurements we wanted to do on the lander uh with kotak and that's the only instrument that could have made this measurement this is to look at the lander with Cotac. And that's the only instrument that could have made this measurement. And this is to look at the hand, it's basically the symmetry of the molecules.

You can either have left-handed, or sorry, hang on, my left-handed or right-handed. And again, it's this connection with the material we see in space and how is it connected to life on Earth. And certain things on Earth have a particular chirality and others have a different chirality and by looking on the comet we'd be matching and seeing if there is a match between the two so are the amino acids on the comet left-handed or right-handed or are they both and vice versa for other things sugars and DNA and this kind of thing and trying to see if there is a

connection with those that we're finding on Earth. The problem is, with the lander, we weren't able to get a sample in the ovens, which was necessary to run a specific part of the COSAC instrument, which was to examine chirality. So without that, now that the lander is most likely not going to function anymore, we have not been able to carry out that measurement. So I just wanted to get back to that part of the question. Oh, nice. Yeah. It still needs doing. Still needs doing. Well, there you go, Josefina.

I believe we have thoroughly answered this question from top to bottom, in and out. Honestly, answering this question was like a cosmic proctology exam. So let us move on. Look at Matt laughing.

I'm going to have to quote you on that. This is Sven Rosandic. I don't know how to say his last name. I'm sorry, Sven. Rosandic. Where's he from? I don't know, but with a name like Sven, I think he's a Viking. Um,

so, uh, this is what Sven says. Uh, he doesn't tell us where he's from, but he's writing to us from Facebook. Um, this is what he says.

Would it be possible to land a spacecraft such as Rosetta on a comet and then stay in contact with it so that every few years it sends us more information. And so I'm going to add on to that with that in mind. Would we be able to land on a comet, say for instance like Halley's Comet, which we know leaves our solar system, goes and then comes back. and then comes back, will we be able to do what Sven said and then get readings from that comet wherever it goes and then gather those readings when it comes back to us? I mean, kind of.

There's a lot to say with this answer, really. It's more that, yes, you could in theory, but the problem is when comets get really far away from the earth and the sun it gets really cold and communications take forever so you're going to have to put that spacecraft into hibernation most likely like we did with rosetta as it was trying to catch up with the comet 67p it got very far away right um so it had to go into hibernation go to sleep for a couple of years um so you you could do that um you need to leave a little bit on because it needs to stay warm in order for the instruments to actually kind of work otherwise they're just going to completely freeze and be

broken so if you could do that bring it back in um turn it back on not always that easy when we had to bring rosetta out of hibernation that was stressful because we didn't know it was going to turn back on it was like you know matt i mean you can probably add something to this i mean i was there watching it on you know the internet feeds but i was stressed you know and we got the signal and it took longer than we thought and i mean it must have been but you were you in mission control for this yeah i was it was fine it was it was fine he's like i play it down there's been so much happening since then but i was like piece of cake that That was all right. Yeah, nothing to it.

But I mean, we, we put the, you know, the best people had designed this to happen. So, so we'd done the best job of getting out of hibernation. So,

and as you said, it had been delayed a little bit, but in the end it did come back. In fact, when you talk about stress, the one guy I remember who looked the most stressed was the person that was involved in writing the software for the hibernation exit and he looked much uh he was the most relieved person in the room i can imagine i can imagine yeah that would be yeah because at that point it's all on him and you know everybody's going

to point their finger even though they're not physically pointing a finger they're just like yep thomas totally yeah i think i would have fainted when that happened you know it's the truth it's just like you know what i mean it's like alex rodriguez uh in the bottom of the ninth and the bases are loaded and you're up to bat and And you know, when you strike out, people are just like, what a waste of $30 million. Nobody says like, it's okay. Everybody says it's okay. But you know what they're really thinking is, dude, you just wasted all of our money. And that's what Thomas, thanks for the program. You screwed us all.

Yeah. So I can imagine that is pretty stressful. But yes, so in theory, Matt, I think, you know, we're running out a little bit of time on this segment. Are we running out? But I think it's kind of possible, but it probably isn't the most important thing for us to be trying to do, because it's better to go to an asteroid or a comet

and measure it and then get done with. Theoretically, I would love to bring samples back. That would be the best thing. So it's more important to get on that comet as it's traversing close enough to our solar system. Yeah. Land on it, get something off of it. And come back. And bring a physical sample home. Exactly, which is what we're trying to do with some of the future asteroid missions.

Okay. Okay, so we're going to wrap it up there for this section, but we're going to be right back. Some more Cosmic Queries when we come back with StarTalk All-Stars. Welcome back to StarTalk All-Stars. I'm Natalie Starkey. Still here with me is Chuck Nice and Matt Taylor from the European Space Agency. Yes. We're going to carry on with some more cosmic queries. More cosmic queries. Inquiries from the internet. That's my new song.

It's lovely. Yeah, my album drops on Tuesday. Thank you. All right, here's the deal. I lost the question I wanted to. Here it is. Graham Woolley. Graham Woolley wants to know this.

Why are plutoids made of different material than comets? Their origins are both trans-Neptunian. Oh, wow. Okay. This is a guy who... He knows what he's talking about. He's a guy who read an article in Scientific American. I think so.

I'm telling you right now. He knows his stuff. Okay. Okay. So let's break this down a little bit. We've got the Kuiper Belt or the Kuiper Belt, however you want to say this. You know what's funny? I, you know, of course, doing this job here, I get to talk to a lot of scientists.

Yep. And I still don't know if it's Kuiper Belt or Kuiper Belt. Because I hear so many of you say it both ways. I say Kuiper. You say Kuiper. Matt, what do you say? I think I oscillate. I think it's Kuiper.

You're Kuiper? I think it's Dutch origin. Okay, so yeah. Okay. So Neil says Kuiper, you say Kuiper. Matt, you say Kuiper, but I know several physicists

who say Kuiper. Yeah, I think that's what Matt said. Yeah. Is Matt Kuiper too? Yeah.'s what matt said yeah is matt kuiper too yeah so i'm in the middle somewhere always the politician matt look at you the diplomat right all right go ahead we have the kuiper belt this is kind of way out past neptune and the solar system not as far as the oort cloud we also have comets but the kuiper belt is important there's a lot of comets there it's also also where kind of Pluto happens to be.

So we've got objects like Pluto. Now, the difference is that we've got objects like Pluto that are round and contain a lot of ice, but seem to look a bit like a planet. That's why Pluto used to be a planet. Unfortunately, no longer. Neil killed it. Yeah, he did. Yeah, he killed it.

Thanks, Neil. no longer. Neil killed it. Yeah, he did. Yeah, he killed it. Thanks, Neil. Then we have the comets, which are the remnants of the very earliest parts of the solar system, the remnants of this dust cloud that we started with. They also contain a lot of ice. Now, we still don't really understand where all of these objects came from and exactly where they formed. Now, it's thought that we've got the Kuiper Belt, which is closer in, and the Oort Cloud, which is further away. We actually think that the Oort Cloud comets formed closer into the sun than the Kuiper Belt initially. And actually, they were so close to the sun that they kind of interacted with some of the inner planetary bodies and were kicked way out of the solar system. So when we see them coming in to the inner solar system occasionally, and we can

look at them with telescopes and even go to them with missions, we actually see their particular composition. And when we measure the ones from the Kuiper Belt, they're different. But then we've also got the Plutoids, which are another kind of family of objects out there. The problem is they're all really far away, and we don't go to them. You know, we've now, with the New Horizons, of course, we have been out this far. And, well, some other missions have been that far as well but in specifically to look at these objects um so we're still learning about them so i kind of like can't answer the question that well matt do you have anything to add because it's like we just we need to just learn more about

these things yeah i think that's the thing is trying to constrain what you call a particular thing and that's the thing you start associating names to different objects. And, well, as you're alluding to, the Kuiper Belt and the Oort Cloud, when you look at 67P with Rosetta, that's a Jupiter-class comet, likely from what we call a very classic and true Kuiper Belt object. We have other Jupiter-class comets that we've observed that have a completely different composition, if I relate to the deuterium to hydrogen ratios, which are kind of a proxy for this whole where they formed with respect to the sun in the early solar system.

And what we found with Rosetta and also the Halley measurements with the similar to 67P showing a broad range of these D to H ratios for a particular class of comets which again mixes up your understanding of the dynamical processes and the evolution for those particular bodies so it's a bit of a difficult mix and when you say right okay copa belt or cloud that's the comets and then we've got the asteroid belt but then most you know in the last 10 or so years people started talking about main belt comets as well so this classification of these small bodies in the solar system is becoming more and more diverse right i think they're all an intermix of everything it's just their evolutionary processes or their evolutionary track has been very different and by doing rosetta by doing new

horizons by doing asteroid missions we try and get a better idea of a one particular asteroid and how that fits into the global picture and all the massive simulations we're doing so it's not an easy one to answer we are learning yeah we are and i mean matt mentioned the um d to h ratios which are really important for understanding these objects and we can actually measure that in kind of on the object um if we can get to it or we can measure it with telescopes now you're then comparing measurements made by different kinds of instruments yes what we're looking at is essentially the composition of the water or ice, water ice or liquid water, mostly ice. Right. And we're looking at the heavy type of hydrogen, which is deuterium in relation to the lighter type, which is hydrogen. And we're literally just looking at the

abundance of those two things. And that tells us a lot about where we think that form all right so let me ask you both this uh based on what we just talked about there um what would you rather have a physical rock sample of an asteroid or a chunk of ice from a comet so which one would you rather analyze matt you can go first which would you prefer oh we've had asteroids so comet we have to have a sample of a comet in in a lab on on earth as ice though that's as ice my part that's what my thing is before that yeah big freeze in a big freezer okay so now now let me ask you because that's a huge, of course, we all see what happens when comets come into the solar system. They get close to the sun. They start to. They do.

And then they just kind of flame out. Yep. So now how, I'm sure this is a stupid question, because if we knew it, we probably would have done. There are no stupid questions. There are no stupid questions. There are no stupid questions. No. I totally disagree with you. When they say there are no stupid questions, I'm just like, you have not heard what I'm about to say.

So, no. Is there plans or a contingency or anything to actually break off a chunk of ice and get it back here. But how would you do that with, but you know, how do you keep something cold enough to get it back to earth so that it doesn't evaporate and disintegrate once it gets, you know, on the journey? It's a massive challenge, but it is something that most sample-based scientists are actively thinking about and trying to work on. Actually, the first place we want to try this is on the moon, because we know we've got ice deposits at the poles of the moon. It's relatively close to us.

We know we can get to the moon. We've done it lots of times. And not saying it's easy, but the challenge will be trying to collect some of these ices from the poles and bring them back as ice. Because you can analyze there. You can go and analyze them with an instrument on the moon. But ideally, we want to bring stuff back because we've got the best instruments on Earth.

We've got the people. We've got the instruments. And we can make the best measurements. And the best instrument of all is the tongue. And you just have a little sip of space water. See what it's like. Yeah. So, yeah, this See what it's like. Yeah. So, yeah, this is what we're trying to do.

I think that's the first step. And then, yeah, if we could bring about ice from a comet, that would answer some major questions about some of the solar system formation. Now, I say that, but the problem is all the comets, as we kind of alluded to, are all different. And although there's going to be groups of comets that are similar, going to one comet isn't actually going to answer all the questions. You know, it's going to help us, but we need to go to lots of them, which is a bit of a problem because

you are very greedy. I am greedy. Very greedy. Look at you. We haven't landed on one. Are you like, oh, we got to get to 15 or 20 at least. Yeah. Actually, just jumping in there, in 1987, when Rosetta was first thought about that was actually a comet sample return that was what it originated as it was supposed to go to a comet and bring a bit back to earth yeah and that was shown to be quite i mean it was uh what we did anyway was quite extravagant i think they were kind of going look look just cut that bit because you're you're going crazy now uh yeah but not a lander, then come back again and then fly all the way back. It effectively makes it like two missions,

so effectively doubles the cost because not only do you have to land, you've got to then launch again and get off the set. Fairly easy on a comet because there's not much gravity. However, the very encouraging and positive thing about this is we're halfway there. We are. We got the first half of the mission done, thanks to Matt and his team, right? We had to prove with Rosetta that we could land on one in the first place. So, you know, this is the thing. When we went to the moon and Mars,

we did lots of orbiters. We did lots of surveying to decide where to land. Whereas with Rosetta, we were doing all of this in one go. In 2014, when we arrived at the comet, we saw what it looked like for the first time. And then we had to land on it within six months and that's important to stress anyway yeah that's really important to stress we'd never seen this thing before the moon we've seen it you know it's right there we can

just look at it and we kind of know what it's what it looks like on the surface what it's made of um but yeah comets we have no idea we've never seen it before so fantastic yeah well graham woolly uh that was a woolly was a great question my friend very nice we got quickly what's that go ahead so you know to sound like to try and bring this all in a little bit but we're not we don't know anything about because we've got so many comments one of the key things with rosetta is uh and as you alluded to about remote observations the thing that we can see these comments from the the ground on Earth and also space-based and Hubble and other measurements like the Herschel Space Telescope, etc.

By having Rosetta sitting there next to a comet and when we're observing it from the ground, it's kind of like bootstrapping a calibration of the ground-based observations. So when we do that cross-comparison between what we see in situ with what we see on the ground for 67P, we can then take those measurements and apply them to all the other cometary observations that we've ever made, and we'll make a future. So it's a nice calibration effect that then expands everything. Almost like we've been to more comets than that. Right, exactly.

So everything that we've already observed, now we can re-observe through the eyes of Rosetta and 67P. Fantastic. That's great stuff. Great point. Great point. All right. Graham Woolley.

Way to go, man. That was a great question. I love it when these people really think very deeply about the questions they ask. Let's go to Maria Macario. Oh, okay. Maria Macario, who writes to us and says this from Facebook. When Rosetta flew by the asteroids 21 Letitia and 2867 Steins, what relevant information did it gather on them? P.S. I hope Chuck Nice doesn't mispronounce my name. Just kidding. I'm sure he will. Well,

she didn't say how we were to pronounce it. This is true. We need phonetically. I screw up everybody's names. It sounded good to me. I hope so. And guess what? If I said it wrong, you should change your name to Maria Macario. So let's talk about these other two asteroids that she said on the flyby.

21 Lutetia and 2867 Steins. Were we able to get any information? Yeah, we got loads of information. So we got loads of images of these things. Nobody's really seen them before. So, you know, beautiful images of asteroids up close, fairly close anyway. And I think also, Matt, am I right in saying we turned on some of the instruments just to have a little test to see that they were actually going to work eventually and kind of sniffed, let's say we sniffed the asteroids.

That's right, isn't it? Yeah, but I think we also ran some of the dust instruments, but they proved that there wasn't really a coma around these objects. So yeah, there were null results, which are results. Yeah. So, yeah, definitely. We got lots of information. So there we go. Yeah.

All right. There you go, Mario. They were like bonuses to the puzzle. Yeah, that was icing on the cake, right? On the way. That was on the way. Exactly. Right.

It's like, you know, it's like car sex on the way home. Oh, my goodness. Yeah. You know, it's really unexpected. We have time for a very short question. Oh, really? Yeah. I love when I make a joke and you can't see it,

but Matt was laughing. And I'm just like, let's move on. I said it's like car sex on the way home. You're like, oh my God. Next question. Matt is cracking the hell up. I love it. Okay, really quick.

All right, let me find a quick, quick question. Quick, quick question. All right. This is Matt Eli from San Antonio, Texas, coming to us from Facebook. Why is the comet surface fluffy? Oh, no, I want longer. I'm going to have to make this really, really short. Okay, so the comet is essentially made of this early gas and dust

from the solar nebula and ice, and it's kind of held together. So this real dust is like the fluff of the solar system. It's not made it into a planet. So the planet's kind of consolidated all this dust and made it solid like the planets. But in the comets, it didn't, because it was kind of a low-energy environment out in the comet formation zone.

So this stuff stayed fluffy, a bit like candy floss kind of thing. So the surface of the comet is very much fluffy. As it goes via the sun, it loses all its ices as it's going and it loses a lot of material. This dust kind of comes off. It dehydrates the surface of the comet. Because the surface of the comet was never compressed to the point where it could be bound tightly? Exactly. So we have a fluffy surface, and I love this stuff. This is what I do.

And the other answer, Matt, is cosmic fabric softener. Okay. And we make, okay, that's interesting. Okay, so we are completely out of time, and i wish we'd had longer for that yeah that was a lot of fun i gotta tell you that was yeah i think we've learned quite a lot i've learned some stuff as well that's good yeah i'm i'm sure it was super cool to have matt here because i gotta tell you having somebody who was actually a part of the mission yeah i mean i really learned a lot this was fantastic we are we're very lucky to have him but But thank you so much, Matt. You've been fantastic as always.

And I love your shirt. So that's cool. Didn't mention that. But that's all we have time for. So, well, thanks. Thanks for joining us. Thanks. Had good fun.

So that's all we have time for today. I want to thank Matt Taylor from ESA who's joined us and Chuck Nice. And that was StarTalk All Stars. I am Dr. Natalie Starkey. This is StarTalk All-Stars. I am Dr. Natalie Starkey. This is StarTalk.