Space in 2021: rovers & a new space telescope
2021 is set to be a jam-packed year for space science. Phil Sansom - and special guests Giles Yeo and Barbara Sahakian - heard from planetary scientist Luke Daly...
Luke - There's a number of missions that are very exciting in that regard, though having said that one of the key missions in my head for 2021 will be the NASA Perseverance rover, and its companion helicopter Ingenuity. They'll be landing on Mars in February of this year.
Phil - What is that doing?
Luke - It's doing a whole bunch of things. Any mission to Mars is searching for evidence of life on Mars, looking for environments that could support life in Mars' past when it was hotter and wetter, all looking for biosignatures: organic compounds and molecules that are sort of the ‘smoking gun’ for past life or modern life on Mars, if any. But it's also got an auxiliary aim, and that is to drill some rock samples from the Jezero crater, cache them away safely, and leave them on the surface of Mars to then be brought back to earth through later missions.
Phil - Here's actually a clip of Chris Smith describing the Perseverance Rover on our show last year...
Chris - It weighs about a ton, it's powered by a plutonium thermoelectric generator, and it even has its own drone. This is like a super yacht with a helicopter on the back.
Phil - It's a bit of a monster here! Is this a first, bringing back this sample, then?
Luke - Absolutely, it'll be the first time we've ever done this. The only samples we have from Mars are meteorites, which is where some large asteroids smacked into the red planet, blasted the rocks off the surface, and sent them spinning on their way to us. Bringing back samples from Mars is a titanic undertaking, and it's been in the pipeline and in the hearts and minds of planetary scientists for as long as I've been alive - and probably a lot longer. And it's really exciting that after all that work and all that effort, Perseverance is the beginning of this Mars sample return campaign.
Phil - When are you going to get the bit of rock back?
Luke - So at the end of a very long campaign, which Perseverance is the beginning; there's going to be an orbiter and lander and ascent vehicle; a mothership to go collect the samples Perseverance cashed, launch them up into a low-earth orbit, capture them with the mothership and send them on their way back to earth. And obviously that all takes time. Not all those missions have been greenlit yet - I really hope they are - and so I've been told anywhere between 2028 and 2032.
Phil - Oh my god! That's a long time.
Luke - That's a long time. It's over a decade. But what heartens me is there's actual physical numbers now. All through my career Mars sample return has always been a decade away, always been a decade away, always been a decade away. Now it's a decade away with actual numbers, and a mission on the ground on Mars caching samples. So we're really excited that this is actually going to happen now.
Phil - Barbara, do you ever get this in your field - you wait a decade for your samples, your data to come back in?
Barbara - I have to say this is really look ahead planning. Obviously you have to have very strong frontal lobe functionality for people who go into this area! I would like to have some studies that do that, because actually it would be wonderful to have the finances to do these longer term studies that go on for a very long time. But what I try to do in my own research is have some studies that are relatively brief in the sense that they go on for a year or two years, and then other studies that may be more three to five year studies; for my own personality and motivation, that's very good to get some short-term gain, as well as look ahead to some longer term very interesting findings.
Phil - How about you Giles? How's your patience?
Giles - I don't see patients personally, I'm a reductionist - I look at coloured liquids. But with that being said, we do take advantage of other people who have done long standing studies. So in particular, we are currently doing a study with a group in Bristol called ALSPAC, Avon Longitudinal Study of Parents And Children. And these are kids born between 1990 and 1992, so we now have this rich longitudinal data. Clearly we're interested in growth and rates of obesity, et cetera, et cetera. And so those are the kind of studies which clearly has taken a long time to put together, close to 30 years now, that we can take advantage of. I don't know if I'd want to set one up myself, I'd have to say!
Phil - Well talking of projects that do take a long time, there's another one that's going up in 2021 that's been in the works for a while. Luke, can you tell us about the James Webb space telescope?
Luke - Yeah, the James Webb is another one that astronomers, astrophysicists, cosmologists have been looking forward to for decades now, certainly longer than I've been in science. It's essentially the mother of all space telescopes. It dwarfs Hubble by six times, so it's mirror is six times bigger. And what it's able to do is essentially look back right to the dawn of our universe, looking at the first galaxies and the first stars that formed right on the edge of what we can see, to really help us understand how our universe came into being, how the first galaxies formed. But also kind of close to home, it can look into our local neighborhood and our galaxy, into the galactic core where stars are forming right now, and the planetary systems around them are starting to coalesce and come together, to really get a handle on how planets form and planetary systems form. There's a long list actually, I won't go through them all; but one of the really cool things it can do is look at and measure the atmospheres of planets around other star systems. So again, looking into habitable worlds: do any star systems or planets, exoplanets, show signs of life or show signs of habitability? By looking at and being able to catch the light that passes from the star, through the atmosphere, kind of like a really distant sunrise, and see how that light is changed by passing through that planet's atmosphere on its way to us, we can figure out what's inside it. So yeah, everything from the origin of the universe to the origins of habitable planets.
Phil - In fact it's such a big operation we actually did a full show about it, but that was back in 2018. And here's Bill Ochs from NASA talking a little bit about the telescope’s design...
Bill Ochs - Our primary mirror of our telescope is about seven times larger than Hubble's primary mirror. That drives a lot of different technologies: we have to be able to fold our mirror up so it fits inside the rocket; since it's infrared, it has to be kept really, really cold.
Phil - It's a bigger operation to get it up there than Hubble was as well - am I right that it's going way far out in space?
Luke - Yes. So Hubble was in Earth's orbit, in its kind of local neighbourhood, where James Webb going is much further out. It's about 1.5 million kilometres away at a place known as Lagrange point 2, which is a place where the gravitational attraction of the Sun and the Earth cancel out. And from there it's stable, it stays in kind of the same spot in relation to the Earth, and can observe the universe around us. Unfortunately, it's far away so unlike Hubble, we can't send a space shuttle up to fix it if anything goes wrong. So once it's up, it's up and we can't bring it back again.
Phil - There's one other thing among the other space projects that are planned for 2021 that I'd like to talk about, and it's the developments with the project Artemis trying to get humans on the moon, maybe more permanently.
Luke - Yeah, so that's again another really exciting series of missions building up to the lunar gateway project, to get a space station in orbit around the moon and get a permanent crude colony on the lunar surface. In the buildup to that NASA and co are going to be testing a bunch of rocketry systems. One really exciting one coming out of the UK is they're going to put a lander on the moon which contains a bunch of different crafts, including one built in the UK, which is the first legged rover. It's about the size of a shoebox, and it's going to be scuttling around on the lunar surface doing some really interesting science. And yeah, it's just going to kind of build up and grow from here. It's a really exciting time to be in space science.
Phil - Giles when people do get up there, they've obviously got some nutritional requirements that need to be dealt with. How are they going to survive and what stuff has got to be kept in mind for them?
Giles - The problem in space is primarily the lack of gravity. And because of the lack of gravity, it's maintaining muscle and bone mass. And now some people think that, “okay, well, I'm going to maintain it by eating protein, because obviously if I eat evil carbs and if I eat fats, all I'm going to do is get fat.” The problem is this: unlike carbs and particularly fat, we don't have stores of protein. So that means that the protein that we eat is functional; it's either gone to repairing damage or building muscles if you're actually exercising. If you don't use it, it gets converted into fat. So I think a critical thing about long-term missions, either in orbit or on the moon in low gravity, is to maintain enough physical activity to maintain your muscle mass and to maintain your bone mass, and obviously then to eat effectively to then keep those growing and building at the right rate.
Phil - Obviously a lot going on in space. Luke, do you think 2021 is going to be an exciting year for space science?
Luke - Absolutely. We're going to be utterly spoiled. There's a whole wealth of really awesome missions going up and coming back this year. So I'm really excited to see the scientific insights we get.