Other Solar Systems

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0:00:27 > 0:00:29Good evening.

0:00:29 > 0:00:32You know, our solar system is one of many.

0:00:32 > 0:00:38One star - the sun, the planets - Venus, Mars, Jupiter and the rest,

0:00:38 > 0:00:40and, of course, our own Earth.

0:00:40 > 0:00:45Are there other solar systems? Surely the answer is yes.

0:00:45 > 0:00:49With me are two experts - Dr Chris Lintott

0:00:49 > 0:00:51- and Dr Lewis Dartnell. - Evening, Patrick.

0:00:51 > 0:00:55First of all, what do we think about finding other solar systems?

0:00:55 > 0:00:59Well, the first thing I think, Patrick, is it's incredibly difficult

0:00:59 > 0:01:02and for hundreds of years people have speculated

0:01:02 > 0:01:04that there might be planets around other stars

0:01:04 > 0:01:07but we haven't had the tools we've needed

0:01:07 > 0:01:11or the techniques we've needed to go after them, until recently.

0:01:11 > 0:01:16The key, it turns out, is to look very closely at the stars themselves.

0:01:16 > 0:01:20The first method that was used to discover planets

0:01:20 > 0:01:23is called the wobble method, the radio velocity method.

0:01:23 > 0:01:27I think I'm going to demonstrate this by picking up the sun over here -

0:01:27 > 0:01:28which we can only do on this scale.

0:01:28 > 0:01:31Actually this isn't the sun, this is a distant star.

0:01:31 > 0:01:34We've got a big, juicy, gaseous planet there.

0:01:34 > 0:01:37What I want you to imagine is that this planet is orbiting the star.

0:01:37 > 0:01:41What's happening is that the star's gravity is pulling on the planet

0:01:41 > 0:01:43but the planet's gravity is pulling on the star.

0:01:43 > 0:01:48And so the star is drawn towards the planet so we get the slow wobble

0:01:48 > 0:01:52back and forth as the planet moves. Now, it's not a very big wobble.

0:01:52 > 0:01:56In our solar system, more than 99% of the mass is the sun.

0:01:56 > 0:01:59But it does wobble nonetheless at about walking speed,

0:01:59 > 0:02:01a few metres per second.

0:02:01 > 0:02:04By looking very carefully at the light we get from the star,

0:02:04 > 0:02:07we don't see the planet but we do see this wobble.

0:02:07 > 0:02:10Then we can detect that there's a planet there

0:02:10 > 0:02:14and, Lewis, we can find out something about the planet itself.

0:02:14 > 0:02:16Well, we can because we work out, roughly,

0:02:16 > 0:02:17what the mass of the star is

0:02:17 > 0:02:20from the colour and how bright it is and characteristics...

0:02:20 > 0:02:24- We understand stars.- Well, we've been looking at them for thousands of years.

0:02:24 > 0:02:29Using this method, and we first discovered a planet orbiting at a main sequence

0:02:29 > 0:02:32a normal star back in 1995

0:02:32 > 0:02:38and so today we are very much in the golden age of discovering new worlds orbiting other suns in our galaxy.

0:02:38 > 0:02:41It's like being back in the 1500s and discovering new continents.

0:02:41 > 0:02:44We're discovering new worlds now.

0:02:44 > 0:02:47Have we any idea what these planets have been like?

0:02:47 > 0:02:52The very first planets we discovered were the easy ones to spot -

0:02:52 > 0:02:55they were the fat, gassy planets like Jupiter

0:02:55 > 0:02:57and they tend to be orbiting very closely to the star,

0:02:57 > 0:03:03because they had the greatest effect on the tugging back and forth.

0:03:03 > 0:03:07So the closer they are, the bigger the wobble, and so the first planets we found were these hot Jupiters -

0:03:07 > 0:03:11these very big planets often bigger than Jupiter,

0:03:11 > 0:03:13very, very close to their parent stars,

0:03:13 > 0:03:15orbiting in just a few days in many cases.

0:03:15 > 0:03:18- They must be weird worlds, don't you think?- Weird indeed.

0:03:18 > 0:03:22I am prepared to believe that somewhere in the universe

0:03:22 > 0:03:24there may be an intelligent astronomer

0:03:24 > 0:03:27who looks like a cabbage and squeaks like a mouse.

0:03:27 > 0:03:30- I can't actually prove it.- You'll need to find the right world.

0:03:30 > 0:03:33I was going to say, I thought you were describing

0:03:33 > 0:03:35some of our colleagues there, Patrick!

0:03:35 > 0:03:37We have started to read the chemistry

0:03:37 > 0:03:40- of some of these extra-solar planets, the atmospheres.- Oh, yes.

0:03:40 > 0:03:43People have spotted the signature, the fingerprint, in the spectrum

0:03:43 > 0:03:45and the colour of the light from the planet.

0:03:45 > 0:03:49They've detected water vapour and carbon dioxide and methane.

0:03:49 > 0:03:52So the beginnings of chemistry and characterising these planets.

0:03:52 > 0:03:54Those are the three things needed for life.

0:03:54 > 0:03:57What about Jupiter's moons? If you put one of these hot Jupiters

0:03:57 > 0:04:00and it has moons just like Jupiter and Saturn do,

0:04:00 > 0:04:02maybe they're worlds where life can exist.

0:04:02 > 0:04:05Exactly. You need the right kind of world to host life.

0:04:05 > 0:04:07Perhaps a rocky world like Earth

0:04:07 > 0:04:10or maybe an icy world with a molten water ocean beneath it,

0:04:10 > 0:04:11somewhere like Europa.

0:04:11 > 0:04:14But it's not just the kind of world you need

0:04:14 > 0:04:16but the location of that world in its solar system.

0:04:16 > 0:04:21So, we can perhaps demonstrate this. Keeping with our sun there.

0:04:21 > 0:04:22I'll pick up our Earth.

0:04:22 > 0:04:27Our Earth has a particular orbit around our sun. It takes one year

0:04:27 > 0:04:30and it's a surprisingly circular orbit around our sun.

0:04:30 > 0:04:33But the distance of the Earth away from our sun is very important.

0:04:33 > 0:04:36It's the right distance from the warmth of the campfire

0:04:36 > 0:04:38that the temperatures on Earth are just right for life.

0:04:38 > 0:04:42If the Earth was closer to the sun, perhaps like Venus or Mercury.

0:04:42 > 0:04:48- Do we have a Venus. There we go. - It would receive too much heat and now its oceans would've boiled away.

0:04:48 > 0:04:51It would be a hothouse, greenhouse world, as we find Venus today.

0:04:51 > 0:04:54If the Earth had formed further from the sun,

0:04:54 > 0:04:56from the heat of the campfire,

0:04:56 > 0:05:01- it would have frozen over and become like Mars.- We come to Mars.

0:05:01 > 0:05:03So, Earth is kind of in that sweet spot

0:05:03 > 0:05:06between being too hot and close like Venus

0:05:06 > 0:05:09and being too far away like Mars.

0:05:09 > 0:05:13Earth orbits in this magical region, this ring around every star.

0:05:13 > 0:05:15You can calculate it for different kinds of stars.

0:05:15 > 0:05:19The temperature on planets orbiting within that inhabitable zone

0:05:19 > 0:05:22would be conducive to liquid water and therefore possibly life.

0:05:22 > 0:05:25It's those kinds of planets we're most excited to find.

0:05:25 > 0:05:27- In fact, we've just found one. - Yes, indeed.

0:05:27 > 0:05:32The first planet in its habitable zone to be properly confirmed

0:05:32 > 0:05:34was announced just a few weeks ago.

0:05:34 > 0:05:37That was Kepler-22b - terrible name, but nevermind.

0:05:37 > 0:05:41That was found by a different method called the wink method.

0:05:41 > 0:05:44So, maybe I'll be the sun again.

0:05:44 > 0:05:48Imagine this Earth-like world is Kepler-22b.

0:05:48 > 0:05:51It can orbit in different ways.

0:05:51 > 0:05:54You can imagine in any solar system just like our own,

0:05:54 > 0:05:57you have all the planets orbiting at a particular plane.

0:05:57 > 0:06:00Just by chance, some of these alien solar systems

0:06:00 > 0:06:02will be inclined and angled directly towards us

0:06:02 > 0:06:04from our telescopes on Earth.

0:06:04 > 0:06:09So you'd see it orbiting around like this. From this point of view,

0:06:09 > 0:06:13you can see the planet passing in front of the star, blocking out

0:06:13 > 0:06:19some of its light as it transits or creates a mini-eclipse of that sun.

0:06:19 > 0:06:20We know its radius, its size.

0:06:20 > 0:06:25We know it's just over twice the width of Earth. We don't know its mass.

0:06:25 > 0:06:28We think it could be up to 30 Earth masses,

0:06:28 > 0:06:30if it's quite gassy, like Neptune.

0:06:30 > 0:06:33In a best-case scenario, it might be all the way down to ten Earth

0:06:33 > 0:06:38masses so it's still a super, a very heavy planet compared to our home world.

0:06:38 > 0:06:39If it's a waterworld,

0:06:39 > 0:06:42if it's covered in more ocean and less rock, it might be down to

0:06:42 > 0:06:46ten Earth masses, but it will still have substantially greater gravity.

0:06:46 > 0:06:49If there was life here, you'd be on an ocean world

0:06:49 > 0:06:52and to support all your weight, like a whale, the water buoyancy

0:06:52 > 0:06:55taking on that weight.

0:06:55 > 0:07:00It's a wonderful thought, the whales of Kepler-22b.

0:07:00 > 0:07:03I get sick of remembering catalogue numbers.

0:07:03 > 0:07:06Kepler-22b I can manage, but Gliese 581b, C, D and E...

0:07:06 > 0:07:08You have enough trouble with asteroids.

0:07:08 > 0:07:12Exactly. If people named asteroids, there would be plenty of those.

0:07:12 > 0:07:15- Would you name extra solar planets, Patrick?- I would, yes.

0:07:15 > 0:07:20- What would you call them? What's your first nomination?- Nemo.- Why Nemo?

0:07:20 > 0:07:23- The unknown.- OK. I like that.

0:07:23 > 0:07:26I'm going for Chris and Lintott would be a good second one.

0:07:26 > 0:07:32- For its moon maybe.- Names are memorable and these are worlds.

0:07:32 > 0:07:36There's a lot of imagination and they've got their own climates and atmospheres.

0:07:36 > 0:07:39What was surprising though, and that's the recent discovery -

0:07:39 > 0:07:41if you believe the results,

0:07:41 > 0:07:45that everything we've been saying, all of these planets orbiting stars,

0:07:45 > 0:07:49they may be in a minority in the galaxy or at the very least

0:07:49 > 0:07:52there may be a whole other class of planet out there,

0:07:52 > 0:07:55and these are the free-floating planets.

0:07:55 > 0:07:56What can these worlds be like?

0:07:56 > 0:08:01Well, they must be reasonably large to account for the signal we see.

0:08:01 > 0:08:04They must be freezing cold,

0:08:04 > 0:08:05cos they don't have star light.

0:08:05 > 0:08:09What happens to Jupiter if you chill it down to minus 270,

0:08:09 > 0:08:11- does it solidify? - Not all the way through,

0:08:11 > 0:08:14so the point about a lot of these free-floating planets

0:08:14 > 0:08:17is that they've still got an atmosphere around them.

0:08:17 > 0:08:22They've still got an insulating atmosphere, and so at the bottom of this it may still remain warm.

0:08:22 > 0:08:25- Of course, they've still got their heat source.- They've still got an internal heat.

0:08:25 > 0:08:28Just like Jupiter and Saturn give out more heat than they receive.

0:08:28 > 0:08:29So, perhaps even a super earth,

0:08:29 > 0:08:32if it gets ejected to the cold depths of interstellar space

0:08:32 > 0:08:36will cool down - it's atmosphere will condense onto the surface

0:08:36 > 0:08:39but underground we've still got all that internal warmth being insulated

0:08:39 > 0:08:42and possibly habitable conditions,

0:08:42 > 0:08:50and so possibly these free-floaters are the most frequent habitable areas - the most frequent life-bearing planets in our galaxy.

0:08:50 > 0:08:53The estimate I saw was that there might be a hundred billion of these things.

0:08:53 > 0:08:55A hundred billion free-floating planets!

0:08:55 > 0:08:58What strange astronomy these people must have.

0:08:58 > 0:09:01If you could develop intelligent life on them...

0:09:01 > 0:09:03Imagine if they did and they got to the stage we're at now

0:09:03 > 0:09:06they would only now be realising

0:09:06 > 0:09:09that there are planets around stars.

0:09:09 > 0:09:11Which would be freaks for them, obviously.

0:09:11 > 0:09:13We would be the anomalies of the galaxy.

0:09:13 > 0:09:16That's a bizarre and slightly scary thought, don't you think?

0:09:16 > 0:09:20We should talk about... Whenever we talk about extra-sol planets, there's something

0:09:20 > 0:09:24slightly unsatisfactory that we can't see them.

0:09:24 > 0:09:26We've got the wobble and the wink,

0:09:26 > 0:09:29- but there's no real substitute for seeing these things.- There isn't.

0:09:29 > 0:09:32One of my favourite results from the last few years

0:09:32 > 0:09:35was the first images of extra-solar planets.

0:09:35 > 0:09:38- I agree on that one.- Particularly...

0:09:38 > 0:09:40I don't know if you can remember the Fomalhaut picture?

0:09:40 > 0:09:43It looked like the Eye of Saruman.

0:09:43 > 0:09:48The image looks odd cos you've got to mask out the light from the star,

0:09:48 > 0:09:50but then you can see it move.

0:09:50 > 0:09:52For me, that's real.

0:09:52 > 0:09:55I say that I believe in these things once I've seen one.

0:09:55 > 0:09:58- And now we have.- That's right.

0:09:58 > 0:10:01We've been talking about life as we understand it.

0:10:01 > 0:10:03What about entirely alien life

0:10:03 > 0:10:06of the kind you find in fiction stories?

0:10:06 > 0:10:09Well as an astrobiologist you need to keep quite an open mind,

0:10:09 > 0:10:11you don't want to get too blinkered

0:10:11 > 0:10:15and think about only the things that we already know because as scientist

0:10:15 > 0:10:16you want to keep your options open

0:10:16 > 0:10:19and look elsewhere and look into other possibilities.

0:10:19 > 0:10:22But I think, at least for the time being, as we're exploring Mars

0:10:22 > 0:10:26and places like Eurpoa and Titan again in the not-too-distant future,

0:10:26 > 0:10:28you want to be focused on what you know works.

0:10:28 > 0:10:31We know that water-based life, and carbon organic life works,

0:10:31 > 0:10:33and perhaps in the further future

0:10:33 > 0:10:36if we don't find any organic life on a place like Mars,

0:10:36 > 0:10:40we might want to think about exotic life on a place like Titan.

0:10:40 > 0:10:42What about looking at the atmospheres of these planets

0:10:42 > 0:10:45cos we're not far off the next generation of big,

0:10:45 > 0:10:48REALLY big telescopes, might be able to take a very close look

0:10:48 > 0:10:50at the atmospheres of these planets.

0:10:50 > 0:10:52Will we be able to see if life exists from them?

0:10:52 > 0:10:55In principal we could, so if we look at some of these Earth-like planets

0:10:55 > 0:10:58that Kepler or other techniques we've been talking about

0:10:58 > 0:11:00and can discover, and in the next five, ten years

0:11:00 > 0:11:04we'll have a shortlist of Earth-like, habitable worlds

0:11:04 > 0:11:06nearby us and we want to check them,

0:11:06 > 0:11:08one by one, with next generation telescopes,

0:11:08 > 0:11:10and look for signs of oxygen in the atmosphere.

0:11:10 > 0:11:14I think the problem of whether there's life in the universe,

0:11:14 > 0:11:16with the discovery of all these planets

0:11:16 > 0:11:19and with the imminent discovery of Earth-like planets

0:11:19 > 0:11:23of habitable zones in sunlight systems, I think has probably shifted

0:11:23 > 0:11:25from being an astronomer's problem,

0:11:25 > 0:11:29to being an astrobiologists problem or maybe even a biologists problem.

0:11:29 > 0:11:32It's about what do we understand about evolution, how does life get started,

0:11:32 > 0:11:35but it's all the more fascinating for that,

0:11:35 > 0:11:37just a little harder to get the answers.

0:11:37 > 0:11:40Patrick, we've been talking about these marvellous

0:11:40 > 0:11:43discoveries from the Kepler spacecraft and just a few months ago,

0:11:43 > 0:11:48I caught up with Bill Borucki who's the man behind it and he was fascinating.

0:11:48 > 0:11:53Since 2009, Kepler spacecraft has been staring

0:11:53 > 0:11:58at a small patch of sky monitoring 150,000 stars.

0:11:58 > 0:12:01It's looking for tiny dips of light as planets

0:12:01 > 0:12:04pass in front of those stars and it needs three of those winks

0:12:04 > 0:12:08to be seen before the team can be sure they're onto something.

0:12:08 > 0:12:11Bill Borucki is the leading light of the Kepler mission

0:12:11 > 0:12:15and is proud to have discovered a multitude of worlds,

0:12:15 > 0:12:18some normal, some exotic and strange.

0:12:18 > 0:12:21I caught up with him at the recent planetary conference in France.

0:12:21 > 0:12:24Of course, we have a lot of candidates and we go through

0:12:24 > 0:12:28a lot of processing to make them announcements but the ones we've

0:12:28 > 0:12:33announced firmly as planets, I think my favourites are the fact that

0:12:33 > 0:12:36we now have one that has six planets orbiting it, transiting.

0:12:36 > 0:12:41We have one where the planet orbits a pair of stars,

0:12:41 > 0:12:44- just like in Star Wars. - Oh, yeah!

0:12:44 > 0:12:45You'd see two stars at sunrise

0:12:45 > 0:12:47and two stars setting at sunset.

0:12:47 > 0:12:51In Star Wars, you see Luke Skywalker looking into the distance,

0:12:51 > 0:12:56you see these two stars setting on the horizon.

0:12:56 > 0:13:00What Lucas got wrong was that he made the blue star small

0:13:00 > 0:13:03and the red star big. Just the opposite case.

0:13:03 > 0:13:05The blue star's the big one. The red star is small.

0:13:05 > 0:13:11We talked to him about that. He said he'll try to get it right next time.

0:13:11 > 0:13:12That's rather nice.

0:13:12 > 0:13:14So, what this is telling us, really,

0:13:14 > 0:13:17is that planets are rather easy to form, I would think,

0:13:17 > 0:13:21if you see them around many stars and you see the diversity.

0:13:21 > 0:13:23Is that the correct conclusion?

0:13:23 > 0:13:29If we want to find an Earth around a star like the sun, if it's a small size, like the size of the Earth,

0:13:29 > 0:13:31you can find that in a week or a month,

0:13:31 > 0:13:34but a habitable sun where the temperature isn't boiling

0:13:34 > 0:13:37then you have to have an orbit very much like the Earth's orbit,

0:13:37 > 0:13:39you have to wait three years for those

0:13:39 > 0:13:40but we are finding small planets,

0:13:40 > 0:13:43and we are finding them around stars like the sun

0:13:43 > 0:13:44but their orbits are too short.

0:13:44 > 0:13:47We're beginning to think about how many large planets

0:13:47 > 0:13:50and Earth-like planets there are.

0:13:50 > 0:13:53Do we have a sense yet of which are more common?

0:13:53 > 0:13:56Is a typical planet like Jupiter or are there more small rocky bodies?

0:13:56 > 0:14:02All the evidence that we have is that the Jupiters are rare.

0:14:02 > 0:14:07The Neptunes and the planets that are super-sized Earths

0:14:07 > 0:14:10seem to be much more plentiful, like ten to one.

0:14:10 > 0:14:13So that would be from a few times the Earth?

0:14:13 > 0:14:17- When you think about these objects, you're asking are they rocky?- Right.

0:14:17 > 0:14:20If the planet's a gas planet, even though it's small, there can be

0:14:20 > 0:14:24no surface and we don't think there's any life cos it's hydrogen.

0:14:24 > 0:14:27- They have moons, though. - It might have moons.

0:14:27 > 0:14:28That's interesting.

0:14:28 > 0:14:31We're finding a fair number of Neptunes

0:14:31 > 0:14:35and Jupiters that in the habitable zone of their stars, but we don't

0:14:35 > 0:14:38think there's life on the planet, but if it had moons, the moons

0:14:38 > 0:14:42are round the planet and therefore, they are in habitable zone.

0:14:42 > 0:14:45You can imagine that you had a Jupiter inhabitable zone

0:14:45 > 0:14:47and had three or four moons like our Jupiter does.

0:14:47 > 0:14:49They are all the size of the Earth.

0:14:49 > 0:14:51They have atmospheres, people on them

0:14:51 > 0:14:55and they go to places for vacations, or visit relatives and so on.

0:14:55 > 0:14:57Do you have a sense of when we will have

0:14:57 > 0:15:00a sense of what the population of planets are out there?

0:15:00 > 0:15:02We still haven't got to the point where

0:15:02 > 0:15:05we're finding Earths in the habitable zone.

0:15:05 > 0:15:08We don't have a lot of confirmed objects in the habitable zone

0:15:08 > 0:15:09so we certainly need more there.

0:15:09 > 0:15:13People sometimes say, "You've found quite a few Jupiters now.

0:15:13 > 0:15:15"Don't you have enough?"

0:15:15 > 0:15:19It's like asking Darwin, "You've seen one finch.

0:15:19 > 0:15:23- "Haven't you seen them all?"- Yeah. Whereas, the variety is the point. - The variety is the point.

0:15:23 > 0:15:26Those differences tell you about their formation, their structure.

0:15:26 > 0:15:30Well, in the meantime, more finches and I hope you'll come back

0:15:30 > 0:15:31and tell us about them.

0:15:31 > 0:15:34- Thanks a lot.- I'll look forward to that.- My pleasure.

0:15:35 > 0:15:39Kepler has recently found Kepler-20e and -20f,

0:15:39 > 0:15:43two rocky planets orbiting the same star, each roughly the same size

0:15:43 > 0:15:47as Earth, but neither of them in that magic Goldilocks zone.

0:15:47 > 0:15:51As the mission rolls on, discoveries like these means it's just a matter

0:15:51 > 0:15:55of time before Kepler finds a planet like Earth, not too hot

0:15:55 > 0:16:00and not too cold and then, the hunt will be on to see if there's life out there.

0:16:00 > 0:16:06We've been talking about other planets, but how are they formed?

0:16:06 > 0:16:09With me are the two Chrises.

0:16:09 > 0:16:12This used to be so simple, we thought we understood how our solar system formed

0:16:12 > 0:16:15but the presence of things like hot Jupiters and so on

0:16:15 > 0:16:17have really confused the picture.

0:16:17 > 0:16:20I think we need to start with star formation.

0:16:20 > 0:16:23- Before you form a planet, you've got to form a star.- Yes.

0:16:23 > 0:16:27A star forms from a huge cloud of gas and dust and the general stuff

0:16:27 > 0:16:31that's out in space and over hundreds of millions of years,

0:16:31 > 0:16:36that collapses down just by gravity and the density

0:16:36 > 0:16:40and the temperature get so hot in the centre that you form stars,

0:16:40 > 0:16:44but that's just the centre cos you've still got this entire cloud of stuff around it.

0:16:44 > 0:16:49Over, again, tens, hundreds, millions of years,

0:16:49 > 0:16:55that flattens down into a disc of gas and dust, so no planets yet.

0:16:55 > 0:16:58If I'm right, the tricky bit is going from dust to gas.

0:16:58 > 0:17:01- Yes.- All the way up to beautiful planets.

0:17:01 > 0:17:05I'm going to give you a wooden spoon. No insult intended by that.

0:17:05 > 0:17:08Stir the bowl in a nice, even manner.

0:17:08 > 0:17:14The water in the bowl is the disc of gas that is orbiting the star.

0:17:14 > 0:17:17- Is that the right speed? - That looks about right.

0:17:17 > 0:17:21We have some pepper and the pepper is going to be the dust

0:17:21 > 0:17:22and we shall see what happens.

0:17:22 > 0:17:27If you take the spoon out... The water's the gas.

0:17:27 > 0:17:30I'm going to sprinkle some pepper on there and very quickly,

0:17:30 > 0:17:34the grains of pepper group together into clumps.

0:17:34 > 0:17:37They sort of do, don't they? It's a bit spiral-galaxyesque.

0:17:37 > 0:17:40What happens to a proto-planetary disc, as we call them, is not

0:17:40 > 0:17:44too dissimilar to what happens in a disc of gas and dust in a galaxy.

0:17:44 > 0:17:46So why is the pepper clumping together?

0:17:46 > 0:17:48Because the tiny grains stick together.

0:17:48 > 0:17:54In a similar way to little grains of dust in a solar system sticking together.

0:17:54 > 0:17:59I believe we now have our first ever image of a proto-planetary disc

0:17:59 > 0:18:00- around Beta Pictoris.- Oh, lovely,

0:18:00 > 0:18:03and this is one of the ones that has planetary systems to it.

0:18:03 > 0:18:06Yeah, so the first amateur image of a solar system

0:18:06 > 0:18:10which has come out recently, which is quite amazing really.

0:18:10 > 0:18:13And your own solar system in a bowl.

0:18:13 > 0:18:16Chris and Chris, thank you very much.

0:18:16 > 0:18:19We have planets on view this month and we still have.

0:18:19 > 0:18:24Peter and Paul are waiting outside to show us Jupiter.

0:18:28 > 0:18:30- Happy New Year.- Thank you.

0:18:30 > 0:18:34It's a bit of a wet, windy one and cold as well.

0:18:34 > 0:18:37We were hoping to see Mars and Jupiter earlier, but I'm not sure now.

0:18:37 > 0:18:40I've set up a pot of tea in the observatory so we can sit

0:18:40 > 0:18:43and wait and see if the clouds part for us.

0:18:43 > 0:18:44- Aren't you a good chap?- I am indeed.

0:18:48 > 0:18:51Some interesting things happening this year.

0:18:51 > 0:18:53We've got that transit of Venus

0:18:53 > 0:18:57and we have some good meteor showers this year.

0:18:57 > 0:18:58The moon's out of the way.

0:18:58 > 0:19:01I'm looking forward to the meteor showers.

0:19:01 > 0:19:03They have been ruined this year

0:19:03 > 0:19:05by the moon being in the way.

0:19:05 > 0:19:06They've been awful.

0:19:06 > 0:19:08We've also got the sun which is waking up at the moment.

0:19:08 > 0:19:11It has looked quite exciting

0:19:11 > 0:19:16and there's been lost of prominences and flares.

0:19:16 > 0:19:18That is exciting because if it carries on building throughout

0:19:18 > 0:19:21the year, that gives us the chance of seeing an aurora.

0:19:21 > 0:19:24Let's start off with the planets

0:19:24 > 0:19:27and the first planet which is Mercury.

0:19:27 > 0:19:28A difficult object to see,

0:19:28 > 0:19:32especially from cities cos it's always rather low down.

0:19:32 > 0:19:35It's said only 1% of the population have ever seen it

0:19:35 > 0:19:36and I don't think that's true.

0:19:36 > 0:19:38It's probably much less!

0:19:38 > 0:19:41It's pointed out month after month, but, during January,

0:19:41 > 0:19:45it can be seen in the first part of January in the early morning sky.

0:19:45 > 0:19:47If you look to the south-east just before sunrise,

0:19:47 > 0:19:49you might be able to pick it up.

0:19:49 > 0:19:52But much more prominently than that is the next planet.

0:19:52 > 0:19:54Of course, the planet Venus, and quite good this year -

0:19:54 > 0:19:58it's going to get reasonably high in the sky for the planet Venus

0:19:58 > 0:20:02and it's one of those friendly objects for amateurs with all scopes,

0:20:02 > 0:20:05or even binoculars cos you can follow the phases, really, with binoculars

0:20:05 > 0:20:07and certainly with a large telescope.

0:20:07 > 0:20:11You can, but the other thing about Venus is that it's so bright,

0:20:11 > 0:20:15I mean, it can cast shadows, it's so bright

0:20:15 > 0:20:18that with the naked eye it looks really stunning.

0:20:18 > 0:20:21In fact, if you go right towards the end of January, there is actually

0:20:21 > 0:20:24a lovely crescent moon very close to Venus in the twilight sky

0:20:24 > 0:20:27and that's one of my favourite sights of all, I think.

0:20:27 > 0:20:31Mars is at opposition in March so it is then visible all night

0:20:31 > 0:20:33and well-placed for being able to see it.

0:20:33 > 0:20:38It's actually not too bad cos it's not moving about a lot in the sky.

0:20:38 > 0:20:39It's close to the rear legs

0:20:39 > 0:20:41of Leo the lion.

0:20:41 > 0:20:44It looks like a bright orangey star.

0:20:44 > 0:20:47This time round, Mars' northern face is presented to us

0:20:47 > 0:20:50so we get a good view of the north polar cap

0:20:50 > 0:20:54and as it's now spring, that enormous polar cap is starting to evaporate

0:20:54 > 0:20:57and fills the air with fogs and mists.

0:20:57 > 0:21:01You get that interesting appearance to Mars.

0:21:01 > 0:21:04One of the most prominent dark features on the surface,

0:21:04 > 0:21:07that V-shaped dark feature, the Syrtis Major,

0:21:07 > 0:21:10which I think always looks like a pair of Y-fronts.

0:21:11 > 0:21:14- Says a lot about your imagination, Pete.- Possibly.

0:21:14 > 0:21:16Let's carry on out of the solar system now

0:21:16 > 0:21:19and go to the biggest planet in the solar system, Jupiter.

0:21:19 > 0:21:21Still blazing away in the sky.

0:21:21 > 0:21:24It's been magnificent over the last few months,

0:21:24 > 0:21:27but there's still plenty to be had with Jupiter.

0:21:27 > 0:21:29It's actually in Aries.

0:21:29 > 0:21:31I think it flips into the neighbouring

0:21:31 > 0:21:34constellation of Pisces, just jumps over the border this month.

0:21:34 > 0:21:36With the naked eye, it looks quite stunning.

0:21:36 > 0:21:39With a pair of binoculars, you can make out those four moons,

0:21:39 > 0:21:42the bright Galilean moons which dance around the planet

0:21:42 > 0:21:45and then with a telescope, you can make out all manner of detail.

0:21:45 > 0:21:47On the subject of Jupiter,

0:21:47 > 0:21:51we have had a lot of wonderful images in to our BBC Sky Flikr site,

0:21:51 > 0:21:54a lot of them illustrating what we've been talking about -

0:21:54 > 0:21:58those really dark barges, the intense brown colour in some of them,

0:21:58 > 0:21:59and of course the great red spot.

0:21:59 > 0:22:01And that region of turbulence

0:22:01 > 0:22:04which is behind the great red spot, it's an amazing thing.

0:22:04 > 0:22:08t is, we're so lucky to have an enormous gas giant like that nearby.

0:22:08 > 0:22:12Let's move onto one of my favourite planets of the entire solar

0:22:12 > 0:22:14system and that is Saturn.

0:22:14 > 0:22:20As you remember, there was that tremendous storm on Saturn.

0:22:20 > 0:22:23We've never seen anything like it.

0:22:23 > 0:22:25It appears it's still going.

0:22:25 > 0:22:28The easiest way to find it is to use that familiar

0:22:28 > 0:22:30pattern of the plough or saucepan.

0:22:30 > 0:22:34- Yes.- You follow the curving handle of the saucepan round,

0:22:34 > 0:22:37you come to a bright orange star known as Arcturus.

0:22:37 > 0:22:39You carry on going and you end up at Spica

0:22:39 > 0:22:41and Saturn is right next to Spica.

0:22:41 > 0:22:43In the constellation of Virgo.

0:22:43 > 0:22:46This time round, now, Saturn has, again,

0:22:46 > 0:22:49got quite a tilt on it now, about 14 or 15 degrees.

0:22:49 > 0:22:53It's northern face is well titled so we're getting a really good view

0:22:53 > 0:22:55of the rings and it looks quite pretty, I think.

0:22:55 > 0:22:59It is quite pretty and if you've got a telescope have a look and see

0:22:59 > 0:23:02if you can find that gap that's between the two bright rings.

0:23:02 > 0:23:04It's a good test of seeing actually,

0:23:04 > 0:23:07you should be able to see it in a six inch reflector.

0:23:07 > 0:23:09OK, so let's move out from the solar system -

0:23:09 > 0:23:12you have an interesting little deep sky thing for us.

0:23:12 > 0:23:17Well, I think it's very sad, as we go into the spring months

0:23:17 > 0:23:21because the gorgeous constellation of Orion

0:23:21 > 0:23:25- rapidly disappears from view. - It does, he's gone!

0:23:25 > 0:23:29It gradually moves to the west and the encroaching twilight

0:23:29 > 0:23:32swallows him up really quickly and we lose him.

0:23:32 > 0:23:35If you go out towards the end of January, don't forget to go outside

0:23:35 > 0:23:39and have a look at Orion hanging there in the night sky. Gorgeous.

0:23:39 > 0:23:42Plenty to look at in the night sky in January, Pete.

0:23:42 > 0:23:44We must have tea in the observatory more.

0:23:44 > 0:23:48- I think it's getting cold. - Let's try it.

0:23:48 > 0:23:50And now for our News Notes.

0:23:50 > 0:23:54Chris and Chris, what's happening in the universe?

0:23:54 > 0:23:58Well, let's start close to home as ever, let's start in the solar system with Vesta

0:23:58 > 0:24:02where we've got these amazing images coming back from the Dawn probe.

0:24:02 > 0:24:04Which has been in orbit now for a few months.

0:24:04 > 0:24:07In fact, it's just reached its lowest orbit which is

0:24:07 > 0:24:11just 130 miles above the surface of this tiny little world.

0:24:11 > 0:24:14And Vesta turns out to be an interesting place.

0:24:14 > 0:24:17But the most remarkable thing is, down near one of the poles,

0:24:17 > 0:24:22this giant mountain, nearly as big as Olympus Mons,

0:24:22 > 0:24:25one of the largest in the solar system, on such a small world.

0:24:25 > 0:24:29- I don't think that was expected. - No-one thought about that.

0:24:29 > 0:24:31Vesta's proved to be a big surprise

0:24:31 > 0:24:35and some of the stuff we've seen happening on the surface -

0:24:35 > 0:24:37little rockslides, landslides,

0:24:37 > 0:24:39and the world is incredibly fascinating.

0:24:39 > 0:24:43I was lucky enough to speak to Chris Russell,

0:24:43 > 0:24:47the lead scientist of the Dawn mission, back in October.

0:24:47 > 0:24:51The Dawn spacecraft went into orbit around Vesta in August 2011,

0:24:51 > 0:24:56and is giving is a unique view of the solar system's second biggest asteroid.

0:24:56 > 0:25:00I caught up with Professor Chris Russell at a recent planetary science conference.

0:25:00 > 0:25:02Chris is in charge of the mission

0:25:02 > 0:25:05and is loving the surprises Vesta is throwing at us.

0:25:05 > 0:25:09We've learned it was a good place to go to.

0:25:09 > 0:25:11And that's important to me,

0:25:11 > 0:25:16because we're trying to go back in time

0:25:16 > 0:25:20and to learn more about the earliest part of the solar system.

0:25:20 > 0:25:25So, did the surface record all of these events?

0:25:25 > 0:25:28We believe, when we look at the surface, it's been a good recorder.

0:25:28 > 0:25:32So this impact crater is about the same size of Vesta itself.

0:25:32 > 0:25:35Its diameter is comparable to that?

0:25:35 > 0:25:40It's very large, we're trying to understand things like,

0:25:40 > 0:25:42what is the age of this structure?

0:25:42 > 0:25:47Is it more recent than the other surface or not?

0:25:47 > 0:25:50We haven't figured that out because there are some areas

0:25:50 > 0:25:52that don't look like they have enough craters.

0:25:52 > 0:25:56But in general, surfaces with fewer craters are considered young?

0:25:56 > 0:26:00Young, and the ones who are heavily cratered are the old ones.

0:26:00 > 0:26:04And, we think we can use the cratering record

0:26:04 > 0:26:07to figure out how old the surface is.

0:26:07 > 0:26:11Dawn has seen more recent features too such as landslides,

0:26:11 > 0:26:15but the scientists are also looking for craters being formed today.

0:26:15 > 0:26:20One of our team members asked us just before we got there and said,

0:26:20 > 0:26:23"could everybody keep their eyes open for fresh craters

0:26:23 > 0:26:26"that appear while we're in orbit.

0:26:26 > 0:26:28"Take a look at those images when we get there

0:26:28 > 0:26:33"and take a look at the images just before we leave and see if anything happens."

0:26:33 > 0:26:36So we might get one so we should be keeping our eyes open.

0:26:36 > 0:26:41Craters expose what's underneath the surface and the fresher the better.

0:26:41 > 0:26:44Looking at craters on Vesta is our way of seeing what the solar system

0:26:44 > 0:26:47was made of 4 billion years ago.

0:26:47 > 0:26:51And seeing something for the first time is always exciting.

0:26:51 > 0:26:53When you see something in high resolution

0:26:53 > 0:26:55you've never seen before, you're surprised.

0:26:55 > 0:26:58Your imagination is great but you can't

0:26:58 > 0:27:00imagine what the surface is going to be like.

0:27:00 > 0:27:05The team is doing a lot of thinking right now and exchanging ideas.

0:27:05 > 0:27:07Sort of like a bunch of kids at Christmas.

0:27:07 > 0:27:11Open a present and say "Look what I got here."

0:27:11 > 0:27:16And then they share and then they opened something else up and share the information.

0:27:16 > 0:27:20Dawn will explore Vesta until later this year,

0:27:20 > 0:27:24and then it's on to pastures new at the solar system's largest asteroid, Ceres.

0:27:24 > 0:27:28Where no doubt, we'll be surprised and amazed yet again.

0:27:28 > 0:27:32There's one other story we have to mention this month, Patrick,

0:27:32 > 0:27:37and that is the first image from a rather obscure camera called SCUBA-2

0:27:37 > 0:27:40which we featured on The Sky at Night a few years ago.

0:27:40 > 0:27:43It's an enormous thing cos it has to be cooled right down cos

0:27:43 > 0:27:45it's going to look in what we call the sub-milimetre -

0:27:45 > 0:27:50the region of the spectrum that allows us to look at some of the coolest things in the universe -

0:27:50 > 0:27:54the places where stars are about to form. They've had a huge struggle,

0:27:54 > 0:27:56it's incredibly technologically complicated,

0:27:56 > 0:28:00at one point they couldn't even get access to their camera

0:28:00 > 0:28:03cos somebody else in the laboratory had poured plutonium down the sink,

0:28:03 > 0:28:06or at least there had been a spillage,

0:28:06 > 0:28:07they just had horrible luck

0:28:07 > 0:28:09and so I've got to show you this image

0:28:09 > 0:28:12which is the first results form SCUBA-2:

0:28:12 > 0:28:14You've got the optical image there

0:28:14 > 0:28:16and then filling in the gaps the detection of light

0:28:16 > 0:28:19from this wonderful camera which is going to help us understand

0:28:19 > 0:28:21star formation and these dark galaxies.

0:28:21 > 0:28:28Of course, we can always find more news on the website:

0:28:28 > 0:28:32You'll also find newsletter 124 which you wrote with Pete Lawrence

0:28:32 > 0:28:34about what to see in the sky.

0:28:34 > 0:28:37Thank you both very much.

0:28:37 > 0:28:41Next month, I will be talking about infra-red astronomy.

0:28:41 > 0:28:44Until then, good night.

0:29:00 > 0:29:03Subtitles by Red Bee Media Ltd