 Thanks, Brad, for the lovely introduction. As Brad mentioned, I'm at the Research School of Earth Sciences. So that's down near the centre of Canberra. But what I like to do is get away when it's not in shutdown and look at rocks. And I look at volcanic rocks from eruptions. I go to Salt Lakes and look at the rocks there. And then I have spent some time being part of the team that's looking at rocks on Mars. So this is part of the Curiosity Rover. Here's the instrument that I helped calibrate and sent to Mars. And we also go up into Arnhem Land and work with the traditional owners on rock art. So I do a range of different things. Today I'm going to talk to you, though, about Mars and exciting things that we have been learning about the red planet, our neighbour. So here's the Curiosity Rover in the Namid sand dune. And you can see that it hasn't got stuck. In fact, this rover's been going for eight years, a few weeks ago. And so it's amazing. It's a very resilient little rover. On its trips, it's collected a whole lot of views of Mars. And so I'm going to just show you some of them. Now, as I mentioned, I'm a geologist. I like rocks. I like sand dunes, too. More sand and rocks. There's a lot of sand and rocks on Mars. Great for a geologist. Very thin atmosphere on Mars. And this is an impact crater. So there's different processes that occur on Mars more frequently than they occur on Earth. It's also very cold. About minus 60 degrees centigrade average. The radiation is strong. Not a good place to hang out, really. It's actually quite inhospitable. But I just showed you that we had spent a fair amount of times with rovers on the surface of Mars. And here are the tracks of the Curiosity rover coming off that sand dune. And it seems you might wonder, why do we go to Mars when it looks so inhospitable and rocky and cold and has very little atmosphere? So why do we do that? Well, the first reason is that humans just love to explore. We've been doing it for thousands of years. And as Brad mentioned, the Australian... Are we to use a transcript? Islanders have been some of the first explorers. Here I'm showing some of the song lines or path trade routes that they used as documented in the 1930s. But they have been using those trade routes for tens of thousands of years. So exploring on Earth and in the oceans is something that we as humans have been drawn to do. But as most of you love astronomy, the sky has also held our fascination. And here are some examples from other parts of the world. Star charts from Egypt and also from China. And we continue to explore. And as you know, one of the places that we explore the planets nearby. This is the launch of the Curiosity rover in 2011. And here I am with my family watching for the countdown. That rocket went really fast. It was there one minute, seemed to hover in the sky. And then 20 minutes later, it was over Australia. So if you want fast transport, take a rocket. Could be confused for some of the places that we have on Earth. So here's some photos of places I've been. And you can see that they have a sort of Mars-like quality. Rocks, dry, red. Not very hospitable looking. But Mars is more like home than any of the other destinations nearby in our solar system. So here's a list of targets that NASA has been considering to visit, to look for, how the solar system has evolved and changed over time. And so you can see Mercury and Venus, Earth and Mars. Mars is the most similar to Earth. Here are some moons. They're very icy, not quite as similar to Earth. So because Mars is so similar to Earth, people have wondered, does it hold the answer to this question that we've thought about for millennia? Are we alone? This has been a topic of many books, movies. You've probably seen some of them. Here I am with ET in Hollywood. It's the real ET. One of the first famous extraterrestrials is ET what we're looking for. What kind of life should we be looking for? Well, there's one option, which is a live life. And then the other option you can guess, dead life or extinct life. So which kind do you think we should be looking for? It's actually both. So that is, we kind of doubt that we'll find a live life, but we'd be happy if we did. We're thinking that it's more likely that we'll find extinct life. So the kind of life that most scientists are looking for is very small. We're not talking about dinosaurs or ET. We're talking about microbes. And microbes are 100s the size of a normal piece of hair. So if you feel your hair and think about how small 100s that would be, that's the size of a microbe. Microbes are important because they represent were the first kinds of life on Earth and the simplest. And they're now really abundant. And so they're a good target for looking for life elsewhere. The first microbes on Earth were found in really old rocks. So rocks that are older than 2.5 billion years old. And you can see Australia has quite a few of those kinds of rocks, particularly in Western Australia. Now, Earth doesn't have as many of those really old rocks as Mars does. On Mars, here, these orange rocks are shown. And those are more than 3.7 billion years old. So scientists think that Mars would be a really good place to go and explore for early life because it has a lot of rocks that formed at the time that life was forming on Earth. So it's a bit hard to search for microbes, as you might imagine, because they're so small. And so scientists have decided that the easiest way to look for microbes is actually to look for the kinds of environments that microbes might like to live in. And so NASA has had a strategy for many decades now of following the water. And the Mars exploration program has relied on looking for water on Mars. Interestingly, indigenous people in Australia have known for years that water is essential for life. Here's some Wajna rock art from the Barnett River in Western Australia. And the Wajna spirits shown beautifully here in this rock art were cloud and rain spirits. And they created the landscapes and continue to have influence over the landscape and the inhabitants. So we're looking for water. But I showed you a whole lot of pictures. And those pictures didn't really have any water in them. And so why are we going from Earth with lots of water to this dry planet that, as I explained before, is not very hospitable for life. It's dry, thin atmosphere, very, very cold. The sun's radiation and cosmic rays hit the surface of the planet. And there's lots of dust and rocks and probably limited life, if any. Well, the reason that scientists go there is we believe that there used to be water on the surface of Mars in the past. And so if we look at the oldest areas of Mars, and so those are the heavily created areas in orange that I showed you before. So yes, Mars is older than Earth in terms of it has more rocks that are old. It's not actually older than Earth. They both formed at the same time. But there's more old rocks. I'm just answering a question I see online. So if we look at those old, old rocks, we see things that look like streams. So on Earth, we have streams will connect up. Little streams will all lead into bigger rivers like this. And we see things that look like legs with streams coming out of them into big depressions that I thought to also have been legs. So Mars does have a little water today. It has it in ice at the poles. So there's dark blue, it's ice. And then it has water bound up in the rocks in the light blue here. So that's in types of minerals called clays and sulfate minerals. So you have those in your garden. There are gullies on Mars and some of the craters. And this is Newton crater. And that's been monitored over the years. And hopefully you can see that going downhill, the surface is changing over time. There's been a lot of argument about these observations. Some people think it's water. Other people think it's just dust going downhill. Anyway, there's multiple lines of evidence suggesting that there may have been water on Mars in the past. So that has been enough evidence to send a bunch of rovers to Mars. And so this one's been eight years on the surface security rover. And what it's been doing is trying to look for a place on the Mars mountain surface that would be a potential place for life in the past or present. And as soon as we got there pretty much, within the first few weeks, a stream was confirmed on the surface. This is confirmed by looking at rocks and seeing these little round pebbles. Can you see them up here in this top right corner? And you can only make little round pebbles like that by moving them in a fast-moving fluid like water. So this be water like the water in a river on Earth. We then travelled around within the first few months and found rocks that had funny little spots in them that geologists think form through the process of water, trickling through the rock. And so these rocks made the scientists on the team very excited because this was a place that we wanted to go and look at carefully with all the tools on the rover to see if these rocks could have hosted life or even have traces of life in them. So that is in fact what we did. We went and drilled these rocks with the rover. So here's an example of a drill hole on Mars. This is the first drilling site. So we did a little test drill hole, not very deep, because this was the first time the drill had been used on Mars and then did a deeper drill hole here. Can you notice something strange? The rock's red over here, but what's being drilled is grey. I'm just going to leave that with you for a while to think about. Okay, so when the geologists went here, we were looking for a few things. Was it a good environment? And the answer was yes, because we found clays, like you have in your clay garden if you live in Canberra or clay you might have used for modelling in class, not very much salt, which is good for microbes and not very acidic, which is also good for microbes. A chemical energy gradient. Well, remember I mentioned this grey versus orange? That's actually a chemical weathering gradient. The grey rock has been oxidised or rusted to make it orange. And so there's a chemical energy gradient. Sometimes it's called a redox or oxidation gradient between the grey and the red. And microbes use that chemical energy to survive. Is there protection from radiation? Remember I said it's pretty horrible radiation. Well, not really, but it's probably the best we've ever seen on Mars, we had seen on Mars at that point because it was a drilled rock. And so we were burrowing down inside the rocks. Was there organic material? So microbes are made of organic material. So if we found organic material we might be able to say something about whether there were microbes there. So even though these rocks were drilled in 2012 this work wasn't done for six years because it had to be done so incredibly carefully. So molecules on earth are in microbes and include a whole range of different potential molecules. Now on Mars there's radiation and the oxidation, the rusting. So we probably wouldn't expect these molecules. There's some traces showing molecules here that were found. And these are very simple molecules, not complicated like these ones and suggest that they probably aren't microbes on Mars. And if they were, they've been extremely degraded. So our best guess at the moment is that we haven't actually found and measured life in these organic molecules. So we're going to go ahead and do a little bit and measured life in these organic molecules. It's probably from meteorites. The exciting thing is we found an environment that could sustain life and where microbes could live. So what's next? Well, on the 30th of July, so a few weeks ago the Perseverance rover shown here on the right which is kind of a twin of the Curiosity rover took off on a six-month trip to Mars. So we're in a good time right now and we're quite close to the orbit of Mars. So that's why this mission went now. Perseverance is going to another crater. It's called Jezero Crater. This is topography map. And it's going to investigate this area here shown in these very strange colors. That are thought to represent what's called a delta. So a delta is where a river comes out into a lake and fills the lake. And as it does that, material is deposited on the floor of the lake building up sticky clay. And that sticky clay ends up having microbes stick to it and as you go into the lake, you get more and more microbes. So here in this picture, we see that this shape is like this. So we'd expect the river is coming down here and we have... Oh, can you see my... I hope you can see my mouse. Anyway, the river is coming down here and we can see these rocks out here and we'd expect them to be... Have more microbes in them if there are microbes there out on these edges. So that's what the exploration plan is. The edges are full of clay, this special kind of clay called smectite and it's shown here in blue and that's where we expect to have lots of microbes. So the perseverance rover is going to go to this area and it's going to investigate these areas that are rich in smectite or clay. And it's going to do that with a whole lot of instruments, radars and lasers and weather stations, cameras, a spectrometer that measures UV light, another one that measures x-rays. That's going to have a bunch of microphones too. Now, my favourite part of the rover is this cool little aircraft that's going to launch from the rover's body. It's called ingenuity and it has a little rotor here so it's kind of like a helicopter because it's flying in the sky and then here it has two camera eyes and it's going to be looking down and trying to help the perseverance rover figure out where it should go. The other part that I really, really like on this rover is that it's going to collect samples. So it has a really big head here. This is bigger than a lawn mower on the end of an arm that's about the length of a lawn mower. And it has drills on the ends of that arm that are going to drill into the rock. And the cool thing about those drills is that they're able to actually create cores of rock so they're like cylinders of rock. So here on the left is an example. The bottom left of a core of rock and then it's going to put it in this sleeve and store that rock inside the sleeve in this container. And this container is called a cache. And then eventually in a few years time the aim is to go collect that cache and bring those samples back to Earth so we can look at them. Now the idea of looking at the rock cores is that the rock cores might have materials in them that have been protected from radiation. And radiation as I mentioned isn't very good for preserving molecules and it destroys them. And so we're hoping that by looking at cores we have a better chance of finding microbes in those clay or smectite-rich rocks. So there's two Australians on this mission. Abby Orwood is from Brisbane. She works at JPL and she's in charge of the X-ray spectrometer. And then on the right David Flannery works in Brisbane Queensland University of Technology and here he is last year measuring rocks out in the Western Australia. Some of those really old rocks and using the drill that they were using on the rover. So there's some Australians involved in this mission which is really exciting. So if you'd like to learn more you can go to mars.nasa.gov and find out more about these exciting missions and upcoming results. So thank you. There are lots of questions here and I think I'll just have to scroll back. So someone says, I understand exploring and curiosity. Why would we want to imagine life on the moon or Mars or another planet when we can't take care of this planet? I actually wonder that myself sometimes. I think that they're different goals. So caring for our planet is something that everybody should be doing. But that doesn't mean that we can't listen to music, that we can't do art, that we can't explore. It just means that it's one of the things that we do. And it turns out that exploring on other planets gives us some options of things to learn about and that may end up helping us take care of our planet. And also turns out a lot of the money that we spend on going to other planets is spent on people's salaries and people developing new things. And so sometimes those new things are helpful for us in our day-to-day lives as well. So I think we should be doing both. I don't think it's and or. I don't think that we have to have a choice between exploring planets and taking care of our Earth. I think we should always be taking care of our Earth and that we can choose to look at planets too. Venus is very hot for this kind of exploration. And so Venus, unlike Mars, is over 350 degrees on the surface and it's got very, very thick atmosphere in clouds. And so we think that it would be quite hard for life to survive on Venus and that it's more likely to be found on Mars. Mars might have underground volcanoes. That's true. Mars might have underground volcanoes. In fact, it might have something called lava tubes. So this is when lava comes out of a volcano and a crust forms on the surface of the lava as it's flowing along. And that crust then insulates the hot lava inside that can still keep flowing through that tube or that crust. And so then the volcano ends up being underground. People think that that might be a reasonable place to go looking for life because the crust of the volcanic rock would have shielded any life from the radiation. Okay, those sand dunes really look like small vows on Earth. Are they similar to what we have on Earth? And yes and no. The gravity is different on Mars and the atmosphere is thinner. And so the wind doesn't move material as much as it does on Earth because the atmosphere is thinner. So they, yes, they're similar but we do have to make corrections for the different properties of the surface and atmosphere of Mars. Can we live on Mars? Not right now. And the reason we can't live on Mars is because we don't have enough resources on the planet to live there. And so we would have to figure out some way to make water for a start and protect ourselves from the radiation as well and keep warm. All of those things are really quite hard to do without fuel. But fuel is really heavy and so it's actually quite hard to take fuel to Mars that's enough to do those kinds of things. So when can I visit Mars? Well, I think we have to solve some of those things first. And I think that bringing back samples from Mars will help us because it will tell us what's there and then what resources are there in a real way. So we've set these rovers and that's great but it's all remote. So can you imagine sending a camera to the bottom of the ocean? You could take photos, look around but it's just not as good as you going yourself, right? Well, it's the same with these rocks. You really want your rocks to come back to you so that you can look at them and multiple people can look at them, check them out and then everyone can decide what's there. When you send the remote camera or the rover to Mars you can't really have that fact-checking and multiple people looking at things because you only have one way of getting the information. It's like sending the camera. It's just one way of getting the information. But if you bring back what you see on the ocean floor then everyone can look at it on the ship. Same with Mars. If we bring back the samples everyone can look at them and then we can come up with better ideas as to what's there. So we can come up with better ideas about what kind of radiation protection might we need. Are those rocks and minerals toxic? All of those kinds of questions we can answer with samples that have been returned from Mars. Wow, there's so many questions here. What got me into looking at rocks? That's interesting. So I just waked being outside and I've never heard about looking at rocks actually. I didn't know that people did that. And a family friend said to me when they heard what I was going to study at university, Penny why are you doing that? I was going to do arts. And they said you'll end up just filing papers in an office somewhere. And I thought oh no, that's the last thing I want to do. I want to be outside. And so she said oh why don't you do geology or geography? And so I decided to do geology. And I decided that rocks were actually pretty cool. Are there any other sites like the one that Perseverance is going to explore? Yes there is. There are actually quite a few sites like that because there are a lot of craters on Mars and lots of evidence for that old water. So yes there are other sites like that. What will happen if extinct life is found on another planet? Hmm. So if extinct life is found on another planet there'll be people that say yes I believe that and there'll be people that say no I don't and there'll be people that the scientists saying we need to test that. And so I think it's going to be ambiguous if we find evidence for extinct life on another planet. I think that the scientists will say we need to test that again and that we need to then check out what's going on with multiple techniques. So I think that's the first thing that's going to happen but I think it'd be very, very interesting. Why is there no water on Mars? You know I'm actually working on that right now and we don't have a very good idea. The main ideas are that it had an atmosphere early in its life that had water in it and it was that the planet couldn't hold on to that atmosphere very well because it's not very big and so gravity didn't hold that atmosphere to the planet and the hydrogen escaped. Now that said there is water in the ice at the poles. So there's not no water because there's water in ice but there's no liquid water. So I might have said that wrong by accident earlier but yeah there's no liquid water and it's liquid water that you need for life. Can we make a rover from an RC car and a GoPro? What is an RC car? I wish that someone could answer me because I don't know what an RC car is. Sorry, remote control car. Ah, okay. Probably could, yep. Now the problem with your rover is it would work on Earth but it wouldn't work on Mars. Now the reason it wouldn't work on Mars is that Mars is so cold that our normal electronics that we're used to don't work very well on Mars. So you have to use special electronics that can survive temperatures that go from minus 120 at night up to 25 or 30 degrees during the day and so if you had a remote control car and a GoPro that had parts in them that could stand up to the temperature cycling yeah, you could. Am I interested in your rover at all? Is it being explored too? Yeah, I love your rover. Your rover is a moon of Jupiter and it's got an icy crust and then it has an ocean that isn't like our ocean with normal salt in it it's an ocean with epsom salts in it so you might have seen epsom salts for the bath so there's epsom salts in the ocean of your rover and then there's bicarbonate soda so that's what you use in the kitchen when you're cooking so your rover is super cool we're not quite sure why it's like how it's become the way it is but there are some plans for exploring your rover in a lot more detail so you can go to the NASA website and learn about that OK, so how do these machines and you need to pick up rock cores get tested on Earth before they start their journey to Mars so what they do is like this picture here this is David Flannery and he has actually got the drill bits this here under his piece of whatever that is, piece of paper is one of the drill bits like the drill bit that they're going to use on the rover and so he's drilling into some rocks that are kind of like the hardness of the rocks on Mars to check it out and test then what they do is they put those onto the rover and they test it on the rover itself sometimes they have a twin rover that they do testing on too but they have to do, I mentioned earlier they have this horrible temperature fluctuation and then they have lots of radiation too so they usually do some testing in a cold chamber they do a testing in a shaking chamber a vibration chamber and they make sure that the parts work before and afterwards and it takes more than 10 years for most of these missions to get ready and so they spend a long time testing I hope you enjoyed that and looking forward to seeing this stargazing even though it's virtual stargazing thank you