0:00:27 > 0:00:28Good evening.
0:00:28 > 0:00:32Now, this programme is going to be about asteroids
0:00:32 > 0:00:35and not everyone will know what they are.
0:00:35 > 0:00:40Well, asteroids are comparatively small worlds
0:00:40 > 0:00:42going round the sun in the same way that we do,
0:00:42 > 0:00:45many, though not all, between the paths of Mars and Jupiter.
0:00:45 > 0:00:48And, telescopically,
0:00:48 > 0:00:50they look like stars, but they are certainly not,
0:00:50 > 0:00:52they are quite different.
0:00:52 > 0:00:54Only one, Ceres,
0:00:54 > 0:00:56is as much as 500 miles across,
0:00:56 > 0:00:58and only one, Vesta,
0:00:58 > 0:01:03is ever visible with the naked eye.
0:01:03 > 0:01:06Well, to talk about those, Chris Lintott, back from America
0:01:06 > 0:01:09and one of my old friends, Alan Fitzsimmons.
0:01:09 > 0:01:11Alan, the Dawn probe has been sent up
0:01:11 > 0:01:13and is now orbiting Vesta.
0:01:13 > 0:01:16Can you take us through the Dawn probe, tell us what it is?
0:01:16 > 0:01:20Well, it's a fantastic mission.
0:01:20 > 0:01:23It's a mission to visit both Vesta and Ceres,
0:01:23 > 0:01:24as you've mentioned already.
0:01:24 > 0:01:28It's in orbit now, about Vesta, successfully,
0:01:28 > 0:01:32and for the next year it's going to be studying, in great detail,
0:01:32 > 0:01:35this amazing world, which we believe
0:01:35 > 0:01:38has been there, roughly in the same place,
0:01:38 > 0:01:41since the dawn of the solar system.
0:01:41 > 0:01:42And it's going to give us clues
0:01:42 > 0:01:46as to how the asteroids evolved over that time.
0:01:46 > 0:01:50And we've got some amazing pictures of the kind we've never seen before.
0:01:50 > 0:01:52Let's have a look at them.
0:01:52 > 0:01:54Well, I mean, these are fantastic images.
0:01:54 > 0:01:57We've had some very low resolution shots
0:01:57 > 0:02:02taken by telescopes on Earth, and, of course, by the Hubble telescope.
0:02:02 > 0:02:04But these show the detail
0:02:04 > 0:02:08that, really, the Dawn mission was designed to provide.
0:02:08 > 0:02:10Mountains, valleys and craters.
0:02:10 > 0:02:15Absolutely. And many of the views of course at the moment
0:02:15 > 0:02:17just of the southern hemisphere of Vesta,
0:02:17 > 0:02:20because as Dawn approached the asteroid
0:02:20 > 0:02:23it came up really from below to get into orbit.
0:02:23 > 0:02:26And that was particularly important for us
0:02:26 > 0:02:27because what we're seeing
0:02:27 > 0:02:31in these first ever close-up images of Vesta
0:02:31 > 0:02:34is the sign of a tremendous impact
0:02:34 > 0:02:38that happened possibly 3.5 billion years ago,
0:02:38 > 0:02:43that literally shook this small world to its very foundations.
0:02:43 > 0:02:46I have to say, I have trouble picking out an impact crater on this image.
0:02:46 > 0:02:50Which of these craters is the impact crater that you're talking about?
0:02:50 > 0:02:54The reason that... In actual fact, I think we all have problems here,
0:02:54 > 0:02:59because here we're looking at a crater that's about the size of the body we're looking at.
0:02:59 > 0:03:01- The whole image is almost a crater. - Absolutely.
0:03:01 > 0:03:04So when we look at this, we see this huge mountain facing us
0:03:04 > 0:03:08that's probably about 15 to 20 miles high
0:03:08 > 0:03:13and about 50, or even 100 miles across.
0:03:13 > 0:03:17So that's what? Three times Everest, if you scale up to Earth size?
0:03:17 > 0:03:19- Absolutely.- Wow.
0:03:19 > 0:03:23About the size of the largest volcano on Mars, Olympus Mons.
0:03:23 > 0:03:27And that is, in fact, the central peak of the crater.
0:03:27 > 0:03:30- So this is material that was thrown up and came back down?- Absolutely.
0:03:30 > 0:03:32And then surrounding it,
0:03:32 > 0:03:35out to about the radius of the asteroid itself,
0:03:35 > 0:03:39is the depression of the bowl of the crater.
0:03:39 > 0:03:42So on the right there, you can almost see those might be
0:03:42 > 0:03:45the walls that were once the walls of the crater, I guess?
0:03:45 > 0:03:46Absolutely.
0:03:46 > 0:03:50- Scattered bits in all directions. - What we now know from telescopic studies,
0:03:50 > 0:03:52in the 1990s and since then,
0:03:52 > 0:03:56is that around Vesta, in the asteroid belt,
0:03:56 > 0:03:58are fragments of Vesta.
0:03:58 > 0:04:03Some of these fragments of Vesta have actually arrived on the Earth
0:04:03 > 0:04:07- and I'm glad to say we have one with us now.- Absolutely, Patrick.
0:04:07 > 0:04:08And here it is.
0:04:08 > 0:04:11In meteoritical terms, this is called a eucrite,
0:04:11 > 0:04:13or a eucritic meteorite,
0:04:13 > 0:04:18and there's two things you can see when you look at this.
0:04:18 > 0:04:22First, we can see it's composed of very angular, small, dark fragments,
0:04:22 > 0:04:25these are the fragments of original basalt
0:04:25 > 0:04:28that have been compressed into a rock by...
0:04:28 > 0:04:31by, literally, other rocks falling on top of them
0:04:31 > 0:04:33due to other impacts.
0:04:33 > 0:04:34Second thing you notice
0:04:34 > 0:04:38is that you don't see any glittering due to metals.
0:04:38 > 0:04:40- No.- And quite often,
0:04:40 > 0:04:43as you know, when you find meteorites,
0:04:43 > 0:04:45- they're highly magnetic... - That's right.
0:04:45 > 0:04:48- ..because they contain lots of iron and nickel.- This one's not.
0:04:48 > 0:04:53Absolutely not. And that's of course because Vesta was differentiated
0:04:53 > 0:04:56and formed its iron core when it was molten.
0:04:56 > 0:04:59All the metals sank down into the centre of body, by and large,
0:04:59 > 0:05:01so this is relatively metal-poor
0:05:01 > 0:05:05compared to an ordinary meteorite that we would find.
0:05:05 > 0:05:09So these two clues tell us that it came from a volcanic body.
0:05:09 > 0:05:12So it's amazing to think that here, in the studio,
0:05:12 > 0:05:16we're actually seeing and touching
0:05:16 > 0:05:18a piece of another world so far away.
0:05:18 > 0:05:20Absolutely, and, of course,
0:05:20 > 0:05:22some might say that if you know so much about it,
0:05:22 > 0:05:24if you've already got a piece here,
0:05:24 > 0:05:26why do you need to send a spacecraft to Vesta?
0:05:26 > 0:05:29- Ah, that's another story! - That's right.
0:05:29 > 0:05:31In fact, it's BECAUSE we have this
0:05:31 > 0:05:36that we know it's worthwhile sending Dawn there in the first place.
0:05:36 > 0:05:40The mission's "Dawn" because we're getting a trace of the early solar system,
0:05:40 > 0:05:43but can you give us a potted history of the solar system?
0:05:43 > 0:05:46We start off with the sun forming and a disc of material around it,
0:05:46 > 0:05:48and then what happens next?
0:05:48 > 0:05:50What happens next is somehow, magically,
0:05:50 > 0:05:53the solar system comes into being.
0:05:53 > 0:05:56And I use that phrase almost literally,
0:05:56 > 0:05:59because we now have some fairly sophisticated models
0:05:59 > 0:06:02- of what happens... - Computer models.- That's right.
0:06:02 > 0:06:03We can't, unfortunately,
0:06:03 > 0:06:07make our own solar systems just yet in real life.
0:06:07 > 0:06:10But these models imply that it was a very turbulent process
0:06:10 > 0:06:13in taking this disc of gas and dust
0:06:13 > 0:06:16and creating a planetary system out of it.
0:06:16 > 0:06:19Because it's turbulent, we have things flying all over the place.
0:06:19 > 0:06:22You've only got to look at the surface of the moon
0:06:22 > 0:06:23to see that, as Patrick knows.
0:06:23 > 0:06:26But what's happening to Vesta at this point?
0:06:26 > 0:06:30We believe that Vesta was one of a population of very large objects -
0:06:30 > 0:06:33several hundred miles across, up to -
0:06:33 > 0:06:35that were formed at this time,
0:06:35 > 0:06:38but most of them have been lost in the subsequent history.
0:06:38 > 0:06:42They've suffered collisions. They've been broken up in those collisions.
0:06:42 > 0:06:45Or they've simply been ejected from the solar system,
0:06:45 > 0:06:48or destroyed by a collision with the sun or another planet,
0:06:48 > 0:06:50and so, when we visit Vesta,
0:06:50 > 0:06:54we really are looking at the last survivor from that epoch
0:06:54 > 0:06:57where the solar system was sorting itself out.
0:06:57 > 0:07:00We know that the probe is now going round Vesta
0:07:00 > 0:07:03and sending back amazing pictures and vast quantities of data.
0:07:03 > 0:07:06Well, eventually, it's going to break free from there
0:07:06 > 0:07:09and go on to the larger asteroid, Ceres,
0:07:09 > 0:07:12which is fainter because it's further out,
0:07:12 > 0:07:14but about 500 miles across.
0:07:14 > 0:07:18Now, Ceres and Vesta are very different, aren't they?
0:07:18 > 0:07:22Ceres, although it would have been heated during formation,
0:07:22 > 0:07:25as Vesta was, and it should be differentiated,
0:07:25 > 0:07:28it should have a core mantle, even-crust structure,
0:07:28 > 0:07:34as Vesta has, but because it's so far from the sun,
0:07:34 > 0:07:38its composition was much more dominated by lighter elements,
0:07:38 > 0:07:43so the rocks on Ceres are much more dominated by,
0:07:43 > 0:07:46for example, carbon and hydrogen and oxygen,
0:07:46 > 0:07:52and, indeed, we believe that within the rocks of Ceres
0:07:52 > 0:07:56there has been the action of liquid water in the past.
0:07:56 > 0:07:59And so, if we want to think of Ceres
0:07:59 > 0:08:02as anything special, we would think of it as a water
0:08:02 > 0:08:05or at least ice-dominated asteroid.
0:08:05 > 0:08:08Any ideas of landing on Ceres?
0:08:08 > 0:08:11Well, that's a possibility, of course,
0:08:11 > 0:08:15just as the NEAR Shoemaker spacecraft landed on Eros.
0:08:15 > 0:08:17More or less by accident!
0:08:17 > 0:08:20- Yes. I mean, it wasn't designed to land.- At the end of its life.
0:08:20 > 0:08:23That's right. Now perhaps the best option
0:08:23 > 0:08:25is that there will be enough fuel left onboard
0:08:25 > 0:08:29to fly Dawn to another, third asteroid.
0:08:29 > 0:08:33There would not be enough fuel to go into orbit about it,
0:08:33 > 0:08:37but we could have another fly-by of yet another unexplored world.
0:08:37 > 0:08:39Well, Vesta was fascinating,
0:08:39 > 0:08:44and before long we're going to hear a great deal more about it.
0:08:44 > 0:08:47Chris, Alan, thank you very much.
0:08:47 > 0:08:49Well, quite apart from the big asteroids,
0:08:49 > 0:08:51there are many, many smaller ones,
0:08:51 > 0:08:55some of which come surprisingly close to the Earth.
0:08:55 > 0:08:57And one did so quite recently.
0:08:57 > 0:09:02Paul Abel has been talking about these near-Earth objects.
0:09:04 > 0:09:08We all lead busy, hectic lives and the thought of an asteroid
0:09:08 > 0:09:10coming at us from the depths of space
0:09:10 > 0:09:12isn't something we worry about a great deal.
0:09:12 > 0:09:16We go to bed at night and presume our civilisation will be there in the morning.
0:09:16 > 0:09:19But there are some big asteroids out there
0:09:19 > 0:09:21with the potential to do a lot of damage,
0:09:21 > 0:09:24and some of them pass dangerously close to the Earth.
0:09:25 > 0:09:28In the sleepy Berkshire village of Great Shefford
0:09:28 > 0:09:30lives an astronomical sentinel.
0:09:30 > 0:09:33By day, Peter Birtwhistle works in IT,
0:09:33 > 0:09:37but by night, he is a defender of the Earth,
0:09:37 > 0:09:39scanning the skies for asteroids.
0:09:39 > 0:09:45Peter took this footage of Asteroid 2011 MD back in June.
0:09:45 > 0:09:47It was the size of a double-decker bus
0:09:47 > 0:09:51and passed just 7,500 miles from the Earth.
0:09:51 > 0:09:55It looks so close you could touch it.
0:09:55 > 0:09:57- Hello, Peter.- Hello.
0:09:57 > 0:10:00Oh, this is a most impressive set-up you have here.
0:10:00 > 0:10:05So, why don't you tell us, then, how did you get involved with 2011 MD?
0:10:05 > 0:10:07Well, I was out observing that night,
0:10:07 > 0:10:12following near-Earth objects that I'd normally do anyway,
0:10:12 > 0:10:16and the discovery was announced about three-quarters of an hour before dawn,
0:10:16 > 0:10:19which gave me just enough time to try and find it.
0:10:19 > 0:10:21You must have been elated when you found it?
0:10:21 > 0:10:24It was one of a couple of objects put on at that time,
0:10:24 > 0:10:26and I chose that one to try and go for it.
0:10:26 > 0:10:28I just had enough time to do so.
0:10:28 > 0:10:32It wasn't where it was supposed to be, so I had to chase it a bit,
0:10:32 > 0:10:35and it was great. By the time I found it, it was just in the nick of time -
0:10:35 > 0:10:38the clouds were rolling in, the dawn was coming up.
0:10:38 > 0:10:41Yes, I know that feeling very, very well!
0:10:41 > 0:10:43So, you found the object, what did you do then?
0:10:43 > 0:10:44Well, as I normally would,
0:10:44 > 0:10:48I just had a look to see where it was going in the next few days.
0:10:48 > 0:10:51I used the discovery positions that were obtained in America,
0:10:51 > 0:10:52together with mine,
0:10:52 > 0:10:55and it worked out the orbit which showed
0:10:55 > 0:11:00that it was going to make a really close pass to the Earth in about five days from then.
0:11:00 > 0:11:02Did you feel, "Oh, my word! This is the end!"?
0:11:02 > 0:11:05Not quite, but it was exceptionally close.
0:11:05 > 0:11:11- It was, yeah.- Right from the very beginning, from that recovery of it,
0:11:11 > 0:11:14it was obvious that it was going to be very close.
0:11:14 > 0:11:16It's always exciting when that happens.
0:11:17 > 0:11:20There are around 8,000 near-Earth asteroids out there -
0:11:20 > 0:11:23too many for professional astronomers to track.
0:11:23 > 0:11:29Amateurs like Peter play a valuable role pinning down these astronomical vermin.
0:11:29 > 0:11:32That could prove vital if one were heading for us.
0:11:32 > 0:11:37In actual fact, what size objects really pose a danger to the Earth?
0:11:37 > 0:11:42Well, a big problem would be a kilometre-diameter-size object.
0:11:42 > 0:11:46- That would cause quite a catastrophe on Earth.- Right.
0:11:46 > 0:11:49There are a number of those that have been discovered, near-Earth objects,
0:11:49 > 0:11:52but all of those have been observed enough to know
0:11:52 > 0:11:55that they won't hit us in the foreseeable future.
0:11:55 > 0:11:57But there is a great potential for material out there?
0:11:57 > 0:11:59Well, there are a lot of smaller ones.
0:11:59 > 0:12:04- Smaller ones, 100-200m across, can still cause regional problems.- Right.
0:12:06 > 0:12:09Our last regional problem happened in 1908
0:12:09 > 0:12:11when an asteroid hit Siberia.
0:12:11 > 0:12:18It flattened 100 million trees over an area of 2,000 square kilometres.
0:12:18 > 0:12:22That's the equivalent of everything inside the M25.
0:12:22 > 0:12:29And I have to ask, if you should discover a tremendously large asteroid heading our way,
0:12:29 > 0:12:31what would you do? I'd go down to the pub.
0:12:31 > 0:12:35OK, no. I'd try and get another few positions on it.
0:12:35 > 0:12:38- Dedicated to the last. Peter, thank you very much.- OK.
0:12:43 > 0:12:46Some time ago, somebody came to me and said,
0:12:46 > 0:12:50"What would you advise me to do if I saw a mile-wide asteroid
0:12:50 > 0:12:54"heading straight for the Earth on a certain collision course?"
0:12:54 > 0:12:57I said, "I'd recommend this -
0:12:57 > 0:13:02"repeat very slowly after me, 'Our Father...' "
0:13:02 > 0:13:05And that's as far as I got.
0:13:05 > 0:13:08At least there's plenty to see in the sky,
0:13:08 > 0:13:11and Pete and Paul are outside waiting for us.
0:13:13 > 0:13:17Well, Pete, only a few hours of darkness at this time of year,
0:13:17 > 0:13:19but, nevertheless, plenty of things to look at.
0:13:19 > 0:13:23- There are. In August, you really have to cram your observations in.- Yes!
0:13:23 > 0:13:25So, what do you think we should look at first?
0:13:25 > 0:13:30Well, we've just been talking about the Dawn mission to go and see Vesta and Ceres,
0:13:30 > 0:13:34so why don't we try and locate where Vesta and Ceres are in the night sky?
0:13:34 > 0:13:39- Amateurs can see them with just a pair of binoculars or a telescope.- Indeed.
0:13:41 > 0:13:44Here we are, Pete, with Patrick's 12.5 inch reflector.
0:13:44 > 0:13:46One of my favourite telescopes here, actually.
0:13:46 > 0:13:50It's the one I normally use. But you don't need a telescope as vast as this to see Vesta, do you?
0:13:50 > 0:13:55You don't at all. Vesta is actually the brightest of the asteroids
0:13:55 > 0:13:58and you can see it in a pair of binoculars fairly easily.
0:13:58 > 0:14:01At the moment, Vesta is actually coming to opposition.
0:14:01 > 0:14:03It comes to opposition on 5th August.
0:14:03 > 0:14:06- So it's opposite the sun in the sky? - That's right.
0:14:06 > 0:14:08That's the time when it's at its brightest,
0:14:08 > 0:14:11and this is a particularly good opposition of Vesta,
0:14:11 > 0:14:14because it will be bright enough to be seen with the naked eye.
0:14:14 > 0:14:16If you're in a dark sky.
0:14:16 > 0:14:19It's slightly brighter than Uranus, not by very much,
0:14:19 > 0:14:21but it is slightly brighter than that.
0:14:21 > 0:14:24A telescope will show its disc, won't it?
0:14:24 > 0:14:26If you've got a big telescope, it has got a tiny disc.
0:14:26 > 0:14:30But really, binoculars are the way to just get a glimpse of it.
0:14:30 > 0:14:32At the moment, it's in Capricornus -
0:14:32 > 0:14:35- the Sea Goat.- But that's not what you've called it.
0:14:35 > 0:14:37It's a bit like a misshapen triangle,
0:14:37 > 0:14:40but to me, it always looks like a misshapen sandwich.
0:14:40 > 0:14:43It ends the month very close to the star Psi Capricorni.
0:14:43 > 0:14:47Oh, very nice. So some easy pointers to find it then.
0:14:47 > 0:14:51Vesta, of course, not the only asteroid we have in the night sky.
0:14:51 > 0:14:52We also have Ceres,
0:14:52 > 0:14:55named after the goddess of cereals!
0:14:55 > 0:14:58So it is, yes! Ceres WAS the largest of the asteroids.
0:14:58 > 0:15:00It's been reclassified now as a dwarf planet.
0:15:00 > 0:15:03What will it be next week?!
0:15:03 > 0:15:06It's actually quite a lot fainter than Vesta,
0:15:06 > 0:15:10and you will need a pair of binoculars or a small telescope
0:15:10 > 0:15:13with a wide-field eye-piece will pick it up as well.
0:15:13 > 0:15:15But it's in a rather obscure part of the sky.
0:15:15 > 0:15:17It's in Cetus, isn't it, the Whale?
0:15:17 > 0:15:20It is. It's quite close to the tail of the Whale.
0:15:20 > 0:15:24The tail is marked by the star Diphda, or Deneb Kaitos.
0:15:24 > 0:15:26- It depends what you want to call it. - I prefer Diphda.
0:15:26 > 0:15:30"Diphda" means "frog", actually. "Deneb Kaitos" means "whale's tail"
0:15:30 > 0:15:34- so Deneb Kaitos is more appropriate. - OK. And this is where we can find this asteroid?
0:15:34 > 0:15:38Yeah. It's moving in quite a small arc around that region,
0:15:38 > 0:15:41so, again, you will need to use optical assistance to find it
0:15:41 > 0:15:45- cos it's fainter than naked eye threshold.- We don't just have
0:15:45 > 0:15:48dwarf planets and asteroids. We also have the other planets,
0:15:48 > 0:15:51- and Mars is making a comeback. - It's been gone for ages.
0:15:51 > 0:15:54- I really miss Mars.- It's returning into the morning sky now.
0:15:54 > 0:15:58So there's a couple of nice events to look out for, isn't there?
0:15:58 > 0:16:01Mars is moving to the south of a rather lovely open cluster
0:16:01 > 0:16:04known as Messier 35 in Gemini.
0:16:04 > 0:16:07Now, have you ever seen Messier 35?
0:16:07 > 0:16:10- Possibly by accident! - THEY LAUGH
0:16:10 > 0:16:13It's a really nice open cluster. In fact, it's a very strange open cluster
0:16:13 > 0:16:16because there is a pattern of stars in there
0:16:16 > 0:16:19that draws the outline of the Space Shuttle coming in to land.
0:16:19 > 0:16:23- Really?- Trust me. It does.- You didn't just make that up?- I didn't.
0:16:23 > 0:16:26If you have a pair of binoculars and you look at M35,
0:16:26 > 0:16:29or at Mars, rather, which will be the brighter object,
0:16:29 > 0:16:32then M35 will be above it on the morning of the 7th of August.
0:16:32 > 0:16:35- That's well worth going to look at. - However, moving on
0:16:35 > 0:16:39from a planet with not much detail on cos it's small to the enormous planet Jupiter.
0:16:39 > 0:16:41This is making an enormous comeback.
0:16:41 > 0:16:43Over the next few months,
0:16:43 > 0:16:46there's going to be one word which will sum up Jupiter,
0:16:46 > 0:16:48and that will be "wow"!
0:16:48 > 0:16:50It's going to be an incredible sight for us.
0:16:50 > 0:16:53It will, and we have some interesting satellite phenomena,
0:16:53 > 0:16:56so its largest satellite, Ganymede...
0:16:56 > 0:16:58The largest satellite in the entire solar system.
0:16:58 > 0:17:02- Bigger than Mercury.- It is, and if you go out on the mornings
0:17:02 > 0:17:06of the 7th, 14th and 21st of August, you'll see Ganymede passing
0:17:06 > 0:17:07in front of the Jovian disc,
0:17:07 > 0:17:09which we call a "transit",
0:17:09 > 0:17:11and Ganymede and its shadow passing
0:17:11 > 0:17:13in front of the disc is quite a spectacle.
0:17:13 > 0:17:16It is. That shadow, when it's on the disc, is incredible.
0:17:16 > 0:17:19- It's so round and dark. - It is very black.
0:17:19 > 0:17:22It's so hard to miss it. I've seen it in a four-inch telescope -
0:17:22 > 0:17:25a beautiful thing, and I'm very excited to have Jupiter back
0:17:25 > 0:17:30because it's been in the murk for all these years, and now it's coming back, and climbing higher.
0:17:30 > 0:17:32It will be about 50 degrees up at its best,
0:17:32 > 0:17:34and that's incredible.
0:17:34 > 0:17:36The view we're going to get of it will be amazing.
0:17:36 > 0:17:38Well, all these wonderful things
0:17:38 > 0:17:41to squeeze into the few small hours of darkness in August,
0:17:41 > 0:17:44- so I think it'd be interesting to go and look at some of those things.- Mm.
0:17:48 > 0:17:51Pete and Paul, thank you very much.
0:17:51 > 0:17:55Back in my study with Chris North and Chris Lintott.
0:17:55 > 0:17:58I'll begin, if I may. A new satellite of Pluto
0:17:58 > 0:18:00has just been discovered.
0:18:00 > 0:18:02We knew of three - the big one, Charon,
0:18:02 > 0:18:05and two small ones, Nix and Hydra.
0:18:05 > 0:18:09This new satellite is small - 20km across.
0:18:09 > 0:18:13There it is. A name has got to be found for it,
0:18:13 > 0:18:16presumably something to do with the underworld.
0:18:16 > 0:18:19Well, my suggestion is Thanatos, after the god of death,
0:18:19 > 0:18:22but I wonder what viewers think,
0:18:22 > 0:18:24so we invite viewers to send in their ideas
0:18:24 > 0:18:27about naming the new moon of Pluto.
0:18:27 > 0:18:29So, there we have the outer solar system,
0:18:29 > 0:18:33but what about the inner planets? Mars back in the news?
0:18:33 > 0:18:36Yes, we talked last month about the sad death of Spirit,
0:18:36 > 0:18:38which has now been abandoned on the surface,
0:18:38 > 0:18:40but its twin, Opportunity,
0:18:40 > 0:18:44roves on. It's just passed the 20-mile mark, would you believe,
0:18:44 > 0:18:46for a mission that - we say all the time -
0:18:46 > 0:18:49was supposed to last 90 days and it's now gone more than 20 miles
0:18:49 > 0:18:51and it's approaching Endeavour crater,
0:18:51 > 0:18:54which is this deep crater that we've been waiting a long while
0:18:54 > 0:18:58to get a look at, so the Opportunity is about to get very exciting.
0:18:58 > 0:19:01And we also have Curiosity, which is the next probe to Mars.
0:19:01 > 0:19:05It's the size of a big car,
0:19:05 > 0:19:08and it's going to do fabulous things and that's been shipped from JPL
0:19:08 > 0:19:11in California, where it was assembled, over to Florida,
0:19:11 > 0:19:13ready for launch later this year.
0:19:13 > 0:19:15What about the landing site on Mars?
0:19:15 > 0:19:18The choice is a wonderful crater called "gaul" or "galle",
0:19:18 > 0:19:19I'm not sure which.
0:19:19 > 0:19:23- Gale!- Well, I was close. So, Gale crater,
0:19:23 > 0:19:26and the thing about Gale crater is it's much deeper than anywhere
0:19:26 > 0:19:27we've visited on Mars before
0:19:27 > 0:19:32and that means you can get much further back into the history of the Martian past,
0:19:32 > 0:19:35so fingers crossed for a safe and rather rocky landing
0:19:35 > 0:19:38and then we'll get to see a lot more of this part of Mars.
0:19:38 > 0:19:40Where next, then?
0:19:40 > 0:19:42We want to go a lot further out. We want to go out
0:19:42 > 0:19:45to the Large and Small Magellanic Clouds.
0:19:45 > 0:19:48The Large Magellanic Cloud is 160,000 light years away.
0:19:48 > 0:19:53It's a small galaxy that orbits our own Milky Way galaxy.
0:19:53 > 0:19:55And the Large and Small Magellanic Clouds
0:19:55 > 0:19:59appear to have a very mixed past. It's something we don't understand.
0:19:59 > 0:20:02The stars seem to have been shared between them somehow,
0:20:02 > 0:20:06- so this is a study of the stars in the clouds.- This is a new result. It turns out that about 5% -
0:20:06 > 0:20:09so one in 20 of the stars in the Large Magellanic Cloud -
0:20:09 > 0:20:12don't look like Large Magellanic Cloud stars,
0:20:12 > 0:20:15but look like their cousins in the Small Magellanic Cloud.
0:20:15 > 0:20:17So the stars must have been swapped,
0:20:17 > 0:20:19and that must have happened relatively recently,
0:20:19 > 0:20:22so these two galaxies, as they orbit the Milky Way,
0:20:22 > 0:20:26must have been interacting with each other, grabbing each other's stars,
0:20:26 > 0:20:32- and I think it's telling us that the area around our own galaxy is quite a complicated place.- Oh, yes.
0:20:32 > 0:20:37We don't quite understand the history of anything we see around us, so that's rather fun.
0:20:37 > 0:20:41- What else do you have for us?- We've gone from the Large Magellanic Cloud
0:20:41 > 0:20:45to something very close to home, which is right behind me here. This is a new award
0:20:45 > 0:20:49from the Royal Astronomical Society that I think you've seen already.
0:20:49 > 0:20:52This is the Patrick Moore Medal, which is not FOR you.
0:20:52 > 0:20:54It's for the teacher or educator
0:20:54 > 0:20:57who's done something remarkable to inspire interest in astronomy,
0:20:57 > 0:20:59and so the Royal Astronomical Society
0:20:59 > 0:21:04have asked us to tell people to send in their nominations for this award.
0:21:04 > 0:21:09Why name it after me? Many people have done so much more than I have.
0:21:09 > 0:21:11- Well, you inspired Chris and I. Right?- Yes.
0:21:11 > 0:21:15It's very easy to nominate people. You can go onto the RAS's website.
0:21:20 > 0:21:24And you can nominate the person or the teacher who's inspired you most
0:21:24 > 0:21:27in astronomy or geophysics. There's one last news note,
0:21:27 > 0:21:29and that's some worrying news from the States -
0:21:29 > 0:21:33Congress are considering cancelling the James Webb Space Telescope.
0:21:33 > 0:21:36- I heard about that. I can hardly believe it!- Yes.
0:21:36 > 0:21:38It will be a disaster for the future of astronomy.
0:21:38 > 0:21:41A short while ago, I went to the Rutherford Appleton labs
0:21:41 > 0:21:46to take a look at one of the instruments being built in the UK to go on the Webb space telescope.
0:21:46 > 0:21:50The Rutherford Appleton lab in Oxfordshire
0:21:50 > 0:21:53is where they design and build telescope instruments.
0:21:53 > 0:21:57The latest is the Mid-Infrared Instrument, or MIRI.
0:21:57 > 0:22:00It will soon be fitted onto the world's most ambitious satellite,
0:22:00 > 0:22:03the James Webb Space Telescope, or JWST.
0:22:03 > 0:22:07Before it can begin its long journey, it has to be tested
0:22:07 > 0:22:10to withstand the conditions it will encounter in outer space.
0:22:10 > 0:22:13'To get close to MIRI,
0:22:13 > 0:22:15'I have to put on this attractive bunny suit.'
0:22:15 > 0:22:18I don't think I've ever been so clean.
0:22:21 > 0:22:24This is the test chamber, and, inside,
0:22:24 > 0:22:27MIRI is being subjected to the harsh conditions of space.
0:22:27 > 0:22:30What we have here is its twin sister.
0:22:30 > 0:22:34Light comes in from the massive telescope to this part down the bottom.
0:22:34 > 0:22:38It's fed up to the camera, where the images are taken,
0:22:38 > 0:22:40and a small amount is sent up to the spectrometer,
0:22:40 > 0:22:43where the light is spread out into its range of wavelengths,
0:22:43 > 0:22:46so we can pick out specific types of element and molecule
0:22:46 > 0:22:49and work out what the chemistry is like in outer space.
0:22:52 > 0:22:55The JWST has a mirror 6.5 metres in diameter
0:22:55 > 0:22:59and will look at longer wavelengths than Hubble.
0:22:59 > 0:23:02This allows it to see cooler objects, providing astronomers
0:23:02 > 0:23:06with views of the formation of galaxies, stars and even planets.
0:23:08 > 0:23:12'Professor Gillian Wright has been involved with designing MIRI
0:23:12 > 0:23:14'and the JWST since the 1990s.
0:23:14 > 0:23:17'It has taken a life's work to help construct
0:23:17 > 0:23:19'the replacement for Hubble.'
0:23:19 > 0:23:23It differs from Hubble in that it's a much bigger telescope
0:23:23 > 0:23:26and we know from the discoveries that have been made
0:23:26 > 0:23:28in the Hubble Deep Field
0:23:28 > 0:23:30that galaxy evolution happened
0:23:30 > 0:23:34much earlier in the evolution of the universe
0:23:34 > 0:23:39than we knew before Hubble, and so what we would like to do is study
0:23:39 > 0:23:41those more distant galaxies and to do that,
0:23:41 > 0:23:44we need a much bigger telescope,
0:23:44 > 0:23:48so that's where JWST will follow from the science
0:23:48 > 0:23:53that's been done by Hubble with new science in complementary ways.
0:23:54 > 0:23:56One of the reasons we built MIRI
0:23:56 > 0:24:00was to try and learn more about how planets form around stars
0:24:00 > 0:24:02and also about how stars form,
0:24:02 > 0:24:06because we know that stars form in very dusty regions
0:24:06 > 0:24:07and so, somehow,
0:24:07 > 0:24:13the chemistry of the dust is all tied up in this process in making it work.
0:24:13 > 0:24:17Taking images in the infrared is technically challenging.
0:24:17 > 0:24:20With a million pixels, MIRI's mid-infrared camera
0:24:20 > 0:24:22is the largest ever built.
0:24:22 > 0:24:26Infrared astronomy has come a long way in just a few decades.
0:24:26 > 0:24:29When I started as a mid-infrared astronomer,
0:24:29 > 0:24:34we had one pixel and that was the best detector you could get!
0:24:35 > 0:24:38Detector technology has changed a lot,
0:24:38 > 0:24:42we know how to do big telescopes in space now,
0:24:42 > 0:24:44with Herschel and JWST
0:24:44 > 0:24:50and so people talk about this now as becoming the era of the infrared
0:24:50 > 0:24:52because a lot of the cutting-edge discoveries
0:24:52 > 0:24:56we expect to come from working at these longer wavelengths.
0:24:56 > 0:25:01Getting MIRI ready for its voyage means testing everything will work
0:25:01 > 0:25:03in the cold, hard vacuum of space.
0:25:03 > 0:25:05Here we are in the MIRI test control room
0:25:05 > 0:25:09and we've got on the screen real data from MIRI
0:25:09 > 0:25:11in its test chamber. What are we seeing here?
0:25:11 > 0:25:14This is the data from the MIRI imager channel
0:25:14 > 0:25:18looking out at the test chamber,
0:25:18 > 0:25:21and it's looking at a tiny point source here
0:25:21 > 0:25:24which we're using to simulate a star.
0:25:24 > 0:25:28Because we're looking in thermal infrared wavelengths,
0:25:28 > 0:25:31you can also see on the image all the structure
0:25:31 > 0:25:34that supports that simulated star.
0:25:34 > 0:25:36So it's looking at something that's the same temperature
0:25:36 > 0:25:39as a cool, brown dwarf, something like that?
0:25:39 > 0:25:44Something about 800 Kelvin, yes, or a very cold star, maybe.
0:25:44 > 0:25:48The JWST is pioneering technology and is technically ambitious.
0:25:48 > 0:25:52Its final destination is a million miles from Earth so,
0:25:52 > 0:25:55unlike Hubble, astronauts won't be able to repair it
0:25:55 > 0:25:56if something goes wrong.
0:25:56 > 0:26:01No-one's ever done a telescope with optics this accurate
0:26:01 > 0:26:05and put it in space before, and it's not really so many years
0:26:05 > 0:26:09since we learned to do telescopes this size on the ground
0:26:09 > 0:26:14and now we're trying to put one in space, and it's also ambitious
0:26:14 > 0:26:16because it's cooled by a sunshade
0:26:16 > 0:26:21and no-one's ever really done a mission which is so totally reliant
0:26:21 > 0:26:23on the sunshade for its cooling,
0:26:23 > 0:26:26so it would be the first time that's done as well.
0:26:26 > 0:26:30And it's deployed, because it's too big to fit in a rocket,
0:26:30 > 0:26:33so we have to unfold the telescope in space.
0:26:33 > 0:26:36In the next few weeks, MIRI will have completed its tests
0:26:36 > 0:26:39and be shipped to NASA to be fitted onto the spacecraft.
0:26:39 > 0:26:41However, with budget problems in the US,
0:26:41 > 0:26:46there is a real threat that the JWST could be scrapped.
0:26:46 > 0:26:50If this happens, the loss to us all would be profound.
0:26:50 > 0:26:54The chance to understand our universe closed for decades.
0:26:57 > 0:27:02So let's only hope that common sense prevails.
0:27:02 > 0:27:06Meanwhile, we've had some lovely pictures sent in and some here of noctilucent clouds
0:27:06 > 0:27:09and these are really beautiful.
0:27:09 > 0:27:11They're incredible. One of the best things
0:27:11 > 0:27:13about observing in the summertime, I think.
0:27:13 > 0:27:17If people want to send in their own images for us to look at or to use
0:27:17 > 0:27:20on the programme, they can do so
0:27:20 > 0:27:23on the Flickr section of our website at...
0:27:23 > 0:27:27And we have some wonderful images there, but the image
0:27:27 > 0:27:28I'll be staring at this month
0:27:28 > 0:27:31is this one from the Herschel space telescope.
0:27:31 > 0:27:34It's an infrared image of our own galactic centre,
0:27:34 > 0:27:35and, if you look carefully,
0:27:35 > 0:27:40you can see this twisted loop of material around the centre itself
0:27:40 > 0:27:44and it's really quite difficult to explain why that material's there,
0:27:44 > 0:27:47or why it's in this twisted form, so I shall be staring at that
0:27:47 > 0:27:49and wondering for most of the next month.
0:27:49 > 0:27:53- I am quite sure you will. - And the image I've picked out
0:27:53 > 0:27:54is one from orbit around Earth,
0:27:54 > 0:27:57an image by an astronaut on the international space station,
0:27:57 > 0:28:00and what's stunning about this is quite how much is in there.
0:28:00 > 0:28:03You've got the solar panels of the space station,
0:28:03 > 0:28:05you've got a part of the space shuttle Atlantis,
0:28:05 > 0:28:08you've got the Earth and the aurora in the atmosphere
0:28:08 > 0:28:12and then you've got some of the star clusters and stars towards the centre of our galaxy.
0:28:12 > 0:28:14This is one of the last times we'll get an image
0:28:14 > 0:28:16with the space shuttle in orbit.
0:28:16 > 0:28:17Thank you both very much.
0:28:17 > 0:28:20When we come back next month,
0:28:20 > 0:28:24we'll be talking about the future of space exploration
0:28:24 > 0:28:27and we'll be joined by astronaut Piers Sellers,
0:28:27 > 0:28:30so, until then, good night.
0:28:41 > 0:28:44Subtitles by Red Bee Media Ltd
0:28:44 > 0:28:47E-mail subtitling@bbc.co.uk