:00:26. > :00:30.Hello and welcome back to Jodrell for Back to Earth, an extra half-
:00:30. > :00:38.hour of stargazing and chatting. There is still time for you to
:00:38. > :00:48.throw us a question to via e-mail - stargazing@bbc.co.uk. We have
:00:48. > :00:51.
:00:51. > :00:55.Professor Brian Cox, Dr Caroline Smith, Tim O'Brien, Dr Richard
:00:55. > :01:02.Greenwood from the Open University and Dr Chris Lintott. We will come
:01:02. > :01:10.to you very quickly. We will hand out drinks. Pass that on. There's
:01:10. > :01:17.some whisky tonight. The distillery have sent - this is whisky as it
:01:17. > :01:25.looks when it comes out initially. Some of this has been sent on to
:01:25. > :01:29.the ISS to see how terpenes in whisky mature in space! LAUGHTER
:01:29. > :01:35.For all those zero gravity whisky distilleries we are planning on
:01:35. > :01:42.building some time! Age? The one we are drinking was nothing to do with
:01:42. > :01:49.space, really! LAUGHTER It is a tenuous thing. It has "space" on
:01:49. > :01:55.the bottle. Really, it is more of a celebration. Congratulations to you.
:01:55. > :02:04.We will need whisky if we are going to go to Mars. It is 500 days there
:02:04. > :02:09.and back. It's just what you need in a confined space(!) As we are
:02:09. > :02:13.discovering tonight! LAUGHTER haven't slept because we have been
:02:13. > :02:18.processing these results. We have found amazing things on Mars.
:02:18. > :02:21.Trying to understand these explosions tells us about the
:02:22. > :02:24.evolution of Mars' atmosphere. It tells us about the changes that
:02:24. > :02:29.happen each season. This is important stuff if we want to
:02:29. > :02:35.understand how Mars works as a planet. Could you speculate about
:02:35. > :02:38.the discovery? The weird terrain? Yes. Those must be cracks, those
:02:38. > :02:43.dark areas. That must be stuff coming up from underneath. It is
:02:43. > :02:49.easy to do science when you know nothing! Stuff coming up to form
:02:49. > :02:53.cracks. Why is it regular? Why do they move? If they move, it must
:02:53. > :02:58.happen suddenly. There is no channels. On other images, we see
:02:59. > :03:03.the same patterns appear again and again. This is a very sudden change.
:03:03. > :03:08.Somewhere else I wouldn't recommend for a spring break. There is no
:03:08. > :03:13.geological parallel you could draw? We played a trick, a blinder on
:03:13. > :03:16.people. We sent you to the least Earth-like place on Mars. We want
:03:16. > :03:21.to understand Mars so you go to where the weird stuff is happening.
:03:21. > :03:31.In science you look for the unusual. There is a geological parallel.
:03:31. > :03:35.
:03:36. > :03:40.Richard and I were talking about it. They do look like December kaigs --
:03:40. > :03:44.dessication cracks. It sort of looks a bit like that. Why that
:03:44. > :03:49.would necessarily move around. see those in the North Pole of Mars.
:03:49. > :03:52.When Phoenix landed, that is what we saw. It is the boring bit of
:03:52. > :03:59.Mars. Phoenix told us it was interesting. These are different
:03:59. > :04:05.from that. They are not - they don't persist in the way that you
:04:05. > :04:10.would expect. The white dots? think they are ice. How large are
:04:10. > :04:14.those blocks? That whole image is two rugby fields. They are quite
:04:14. > :04:24.big. Depending on the actual surface, what the surface is made
:04:24. > :04:29.of. What rocks it is, how fine those rocks are. You could get very
:04:29. > :04:34.coarse dessication cracks like that. You need a liquid phase, don't you?
:04:34. > :04:39.Yes. This is a spring image. So it is the point where that is turning
:04:39. > :04:45.back into gas. The way to check - we have some new images on the site
:04:45. > :04:50.and we have focused on these areas. We will see if they change. This is
:04:50. > :04:56.genuine semi-blind speculation occurring live(!) We call it
:04:57. > :05:05.science! You need to get somebody in the laboratory to get the
:05:05. > :05:10.conditions. Can we go back to the jets? They come out very fast. The
:05:10. > :05:17.faster they come out, the longer they get. I hope we have got the
:05:17. > :05:25.record-breaker we can show you. This goes out to 250, 300 metres
:05:25. > :05:30.and it comes out faster than Usain Bolt! Didn't we something like that
:05:31. > :05:34.on one of Neptune's moons? Yes. That's been suggested that is the
:05:34. > :05:41.same sort of mechanism. We have another one. You wanted a message
:05:41. > :05:50.from the Martians. We have got one. They love you! LAUGHTER This was
:05:50. > :05:53.found by Rob and Ellie Jones. is fantastic! This is the wind
:05:53. > :05:58.blowing material? The wind shifts and you get this change in
:05:58. > :06:02.direction. It is a message for Dara! It is great. They can still
:06:03. > :06:11.take part in this? That's right. We put new images up. We need more
:06:11. > :06:15.people to explore Mars. We have a million questions about how Mars.
:06:15. > :06:22.How has Mars retained any of its atmosphere? Is it on the way to
:06:22. > :06:26.losing it all? Very slowly. It is still losing materials. There are
:06:26. > :06:31.spacecraft measuring the loss of Mars' atmosphere. It's held on to
:06:31. > :06:38.what it's got because it's got gravity. What do you think Mars'
:06:38. > :06:43.atmosphere smells like? It is fairly thin, so very little. What
:06:43. > :06:48.is the composition? It is mostly CO2. There's nitrogen in there.
:06:48. > :06:51.That's one of the ways that we know that Martian meteorites are from
:06:51. > :07:00.Mars because within the Martian meteorites there is this atmosphere
:07:00. > :07:06.which is rich in CO2, nitrogen, things like that. We can measure
:07:06. > :07:13.the isotopic composition of that. How many Martian meteorites do we
:07:13. > :07:19.have? About 100. When I say 100, there are some in the pipeline that
:07:19. > :07:24.are being classified. Compared with the 60 from Vesta, we have five
:07:24. > :07:32.witnessed falls. How come we have got more Vesta than Mars?
:07:33. > :07:42.didn't watch the show! We have covered this topic. Maybe you want
:07:43. > :07:43.
:07:43. > :07:47.to move on! There is a subtle story behind that. It is to do with the
:07:47. > :07:53.solar radiation? They are drifting into the three to one resonance.
:07:53. > :07:57.Are they being pushed? Yes. There is a plan were we to see an
:07:57. > :08:03.asteroid heading towards us, we would paint it white or black in
:08:03. > :08:06.order to use the Sun... You might push it into a situation where it
:08:06. > :08:11.hits the Earth. You have to be certain you know... Or hit a
:08:11. > :08:16.certain part of the Earth! You can have the Americans painting it
:08:16. > :08:20.white and the Chinese painting it black! LAUGHTER You have to know
:08:20. > :08:27.what you are doing. A lot of asteroid questions. Can objects
:08:27. > :08:30.orbit around meteors? Yes, they can. In fact, there's - as we observe
:08:30. > :08:36.asteroids with radio telescopes and observational telescopes, we are
:08:36. > :08:43.finding that binary asteroids are more common than singular asteroids.
:08:43. > :08:49.How large would they have to be? You are talking sort of... Relative
:08:49. > :08:53.to planets? You are talking objects a few hundred metres in diameter.
:08:53. > :08:57.As we heard in the main programme, a few hundred metres wide doesn't
:08:57. > :09:01.sound very wide, but if that hit Earth, we would be in big trouble.
:09:01. > :09:09.Would it be possible for a big enough comet or asteroid to pull
:09:09. > :09:14.Earth out of its orbit? No. They are never that big. The Earth's far
:09:14. > :09:17.bigger... It would destroy life. That is all right then(!) Size
:09:17. > :09:23.always wins. In the past, the formation of the Moon is that we
:09:23. > :09:28.got hit by a planet-sized object. That is one of the most remarkable
:09:29. > :09:38.things in science. Papers came out recently, but the picture it paints
:09:39. > :09:39.
:09:39. > :09:45.is of an horrendous one. The atmosphere was up to 6,000 degrees
:09:45. > :09:50.Kelvin. That is the heat of the Sun! I do want to get you to do
:09:50. > :09:57.something for me, which is to go to the photographs we have received.
:09:57. > :10:07.There's lots more on the website. Please go and check those out.
:10:07. > :10:13.
:10:13. > :10:23.Chris, you have three? I liked these three. This one is M81 Bode's
:10:23. > :10:29.
:10:29. > :10:35.Galaxy. We have the Veil Nebula. It's taken by Rob Preston in July
:10:35. > :10:45.2012. This is often called the Witch's Broom. My favourite - this
:10:45. > :10:52.is from Richard Taylor. We have the beautiful astronomical little
:10:53. > :11:02.startrail there. And a mystic stone circle! Which constituency are you
:11:02. > :11:08.appealing to? They are all watching! We traditionally
:11:08. > :11:18.antagonise these people. We don't mean to! I got a tweet saying why
:11:18. > :11:24.didn't you say anything about astrology being a complete drivel?
:11:24. > :11:30.We are not going to say anything! say half of them - I know people
:11:30. > :11:39.mistake the word s astronomy and astrology. Say the word out loud
:11:39. > :11:49.and it is all in the word. Astronomy, nom, nom, Brian Cox is
:11:49. > :11:59.delicious! LAUGHTER We have discussed meteorites... Carry on!
:11:59. > :12:07.That's for Buzz Lightyear, my friend! Meteorites can tell us the
:12:07. > :12:11.story of our universe. Dr Caroline Smith has brought in some of the
:12:11. > :12:15.rocks from our universe. What do we have here? We shouldn't touch them.
:12:15. > :12:18.I will pull them over here, if that is all right, camera people? We
:12:19. > :12:24.have four meteorites here from the collection. You can see Brian and I
:12:24. > :12:29.have put our gloves on. That is not for any weird sexual interest later
:12:29. > :12:35.on! LAUGHTER It is important to clear that up. This is because
:12:35. > :12:38.these are all actively research specimens by scientists at the
:12:38. > :12:45.museum. What we want to do is try and minimise any contamination that
:12:45. > :12:50.we might add to the meteorites by handling them. I have whisky on
:12:50. > :12:52.that one! Put a new one on. I think in no particular order, this is one
:12:52. > :12:58.in no particular order, this is one here, this is the Murchison
:12:58. > :13:03.meteorite. It fell in Australia in September of 1969. This is a very
:13:03. > :13:06.important specimen because it is full of organic molecules. Full of
:13:06. > :13:16.all the chemical building blocks you need for life to start.
:13:16. > :13:17.
:13:17. > :13:22.Including things like amino-acids. So I know on Tuesday you were
:13:22. > :13:26.talking about this. One of the theories which is a popular theory
:13:26. > :13:29.is that meteorites like this seeded the early Earth with all the
:13:29. > :13:39.chemical building blocks that you need for life. How would they have
:13:39. > :13:39.
:13:39. > :13:44.formed? You need stable conditions. You need temperature gradient. You
:13:44. > :13:48.probably need water? Exactly. This meteorite, very early in its life.
:13:48. > :13:54.This is one that dates back to the first stages of the Solar System
:13:54. > :14:01.forming. This meteorite is full of clay minerals. These are minerals
:14:01. > :14:08.that have interacted with water. So we know that there was water on the
:14:08. > :14:13.parent body of this meteorite. Yes, complex chemistry was going on.
:14:13. > :14:17.Liquid water? Exactly. It's dry now. It would have been - one of the
:14:17. > :14:25.suggestions is that meteorites similar to this, not the same type,
:14:25. > :14:35.may be from comets. This may be part of a comet? Possibly. We think
:14:35. > :14:36.
:14:37. > :14:43.there's pros and cons for that They originated outside the solar
:14:43. > :14:51.system. There is an active debate. Maybe they formed in the cold out
:14:51. > :14:57.parts of the solar system. You need carbon, nitrogen, oxygen, close
:14:57. > :15:01.together, cold, presumably. We see this chemistry. On Tuesday you
:15:01. > :15:06.showed us there was water in the Orion nebula. If we looked at
:15:06. > :15:14.different wavelength we would have seen hydrogen cyanide, ammonia, and
:15:14. > :15:17.we see complicated molecules. Alcohol! Organic chemistry, you
:15:17. > :15:23.think of it as being very, very special, but it is found all over
:15:23. > :15:29.the place. Theatre reaches of the solar system and in interstellar
:15:29. > :15:39.space. Choose one more. This is another super special one. My
:15:39. > :15:44.microphone has fallen off! This is one of our stars of the museum. A
:15:45. > :15:54.meteorite that fell in Egypt in 1911 and it is one of a handful, 60
:15:54. > :15:58.meteorite from Mars. This is a piece of the planet Mars. There's a
:15:58. > :16:03.story that a dog got killed by this, but it's apocryphal. A piece of
:16:03. > :16:10.Mars. If you could scrape off the rusted surface of Mars, you would
:16:10. > :16:14.get this beautiful green/grey rock. This is similar to Roxy would find
:16:14. > :16:20.on her. Similar to volcanic rocks, like you would find on the Western
:16:20. > :16:25.Islands of Scotland. Like the places you get whisky from! We
:16:25. > :16:30.spoke about water and water on Mars, there's a story that a lot of
:16:30. > :16:36.people don't know. Gnats -- NASA announced regularly that they have
:16:36. > :16:39.found water on Mars. In the 1970s a scientist studying this meteorite
:16:39. > :16:46.was the first person to conclusively show that water had
:16:46. > :16:50.existed on Mars in the past. changed the rock. Exactly. There
:16:50. > :17:00.are clay minerals in this rock for a show it has to have interacted
:17:00. > :17:01.
:17:01. > :17:11.with water at some point. Thank you. A question now. It is a relevant
:17:11. > :17:15.
:17:15. > :17:25.Greetings, master, I am a K9. Tonight, as you say, which is the
:17:25. > :17:34.
:17:34. > :17:44.Please furnish me with the correct answer. Who is the odd one out?
:17:44. > :17:45.
:17:45. > :17:55.didn't listen! It was brilliant on Tuesday. World of sport with Dickie
:17:55. > :18:01.Davies. A do you want an answer? Was one of them hit by a meteorite?
:18:01. > :18:06.Yes. Anyone know the odd one out? The lady on the left. Why? She has
:18:06. > :18:14.not been hit by a meteorite. What was she hit by? I don't know.
:18:14. > :18:20.find out. This is the answer. All three of these humans have been hit
:18:20. > :18:30.by objects falling from space. Mrs Hodges and the boy from Uganda were
:18:30. > :18:35.both struck by meteorites, but Rhys Williams is the only known -- Miss
:18:35. > :18:45.Williams is the only known human to be hit by man-made space debris.
:18:45. > :18:47.
:18:47. > :18:54.Now I must return. Farewell. Keep return to his cupboard! How often a
:18:54. > :19:01.people hit by a meteorite? For Ozil the only two people we know what. -
:19:01. > :19:07.- there's a car. There might be others. If they dropped down dead
:19:07. > :19:14.in a quiet area, nobody would know. It increases the value of the car.
:19:14. > :19:17.If your car is hit by a meteorite, it increases the value. Please
:19:17. > :19:23.donated to the Natural History Museum! We can put it on public
:19:23. > :19:30.display. At a man came up to me in Oxford and handed me these,
:19:30. > :19:37.cufflinks made from meteorite. Lee? That was what he said. He said
:19:37. > :19:43.the beans were magic and I gave him the money. We have received any
:19:43. > :19:52.number of serious and semi-serious suggestions for what that image was
:19:52. > :19:56.you were looking for a reason for. Will says, a rock maze created by
:19:56. > :20:01.Martians for thanksgiving. Tomato it -- tomato soup spilled on a
:20:02. > :20:10.picture. My head under a microscope! A Marshin brain. Kilos
:20:10. > :20:15.of people have said it is a Marshin brain. A Martian skate park! And
:20:15. > :20:24.shadows of sand dunes. Is there wind on Mars? Yes, but no shadows.
:20:24. > :20:33.Cobalt and chloride crystallising in funnels. Good for him. Salt
:20:33. > :20:36.plains like in Bolivia, but bigger. Would they be tectonic plate?
:20:36. > :20:42.It is one of the reasons it is different from the earth. It
:20:42. > :20:46.doesn't have moving plates. Rocky debris on top of a glacier? We know
:20:46. > :20:56.there's ice underneath so that is a good description. But how. More
:20:56. > :20:58.
:20:58. > :21:08.detail in your tweet! Only 140 characters! I have to buy a point.
:21:08. > :21:11.
:21:11. > :21:18.-- a pint. Everyone. Everyone on Twitter! What are we going to do?
:21:18. > :21:25.Other questions about asteroids. Some strike and make creators --
:21:25. > :21:29.craters, but we don't see any debris. There was a chap who tried
:21:29. > :21:33.drilling a crater in the 1930s, but the idea he was under the ground,
:21:33. > :21:43.he found nothing. When they get a certain size, the atmosphere does
:21:43. > :21:43.
:21:43. > :21:48.not stop them so they plough in and explode. The desert plains around
:21:48. > :21:53.Arizona were covered Int shrapnel from a meteorite. They play
:21:53. > :21:56.themselves to pieces. Tim, it is not only these massive things
:21:56. > :22:00.coming from space, it's a much smaller things are coming.
:22:00. > :22:04.thought we would scare people. We said meteorites don't often hit
:22:04. > :22:09.people, but what are hitting us all the time of particles from outer
:22:09. > :22:15.space. Very small particles, sub- atomic particles. The interesting
:22:15. > :22:18.bits of the universe. Yeah! We've got a machine built by some
:22:18. > :22:27.colleagues and students from the University of Manchester physics
:22:27. > :22:32.department. If we switch it on, it should detect a... These are heavy
:22:32. > :22:37.a electrons. 200 times heavier than an electronic and they are created
:22:37. > :22:40.when the cosmic ray particles hit the top of the atmosphere at moving
:22:40. > :22:45.at almost the speed of light and it creates a cascade of the secondary
:22:45. > :22:48.particles and radiation floods down through was all the time. Thousands
:22:48. > :22:54.of these things to pass through every square metre of the Earth
:22:54. > :23:04.surface every minute. We have detectors 100 metres below ground.
:23:04. > :23:08.They are massive. You can align all the bits. Even 100 metres down, we
:23:08. > :23:11.use those, they come straight through in a straight line. If your
:23:11. > :23:17.measurement shows it has done that, you know that bit of the Tetra is
:23:17. > :23:22.misaligned. They are very, very useful. There used to be a research
:23:22. > :23:26.area. Now we use them to a line detectors. The highest energy ones,
:23:26. > :23:30.we have no idea where they come from. The highest energy one of the
:23:30. > :23:37.measured was a single proton, probably from outside the Galaxy,
:23:37. > :23:41.that came in and it had the energy of a professional tennis serve. One
:23:41. > :23:48.proton. Can you imagine how one lucky you would be to get hit by
:23:48. > :23:52.that? -- how unlucky. These are ultra-high energy. They would
:23:52. > :23:55.normally decay and other particles within a few microseconds and they
:23:55. > :24:01.would never reached the ground. Because they are travelling at such
:24:01. > :24:08.high speed, especially relativity and time dilation, time slows for
:24:08. > :24:14.them and they lived for longer. and a stick. 2013 promises to be a
:24:14. > :24:19.bumpy year for stargazers. Mark has some of the biggest events to look
:24:19. > :24:24.out for. Come in as soon to a Scaini you.
:24:24. > :24:31.The first date for your diary is fair pre- 15th. That is the day the
:24:31. > :24:38.45 metre wide asteroid 2012 DA14 will visit and, approximately
:24:38. > :24:43.35,000 miles from our surface. -- and come. 28th April, the
:24:43. > :24:47.spectacular ring of Saturn will be in opposition. That means it is at
:24:47. > :24:53.its closest point to the air. It will reach its highest point at
:24:53. > :24:57.midnight. One month later on April -- made 28th, Venus and Jupiter has
:24:57. > :25:02.turned to put on a brilliant show. The two brightest planets we can
:25:02. > :25:07.see will be in conjunction, lining up in the sky. Look up in August
:25:07. > :25:14.and you could see up to 90 meteors in an hour. It is the annual
:25:14. > :25:22.prescient -- Perseid meteor shower. Last but by no means least, what
:25:22. > :25:27.some are calling the comet of the century. At the end of the year,
:25:27. > :25:31.Comet ISON could be dazzling and possibly brighter than the full
:25:31. > :25:38.moon in daylight. But this one might still turn out to be a damp
:25:38. > :25:42.squib. Why would it be so spectacular?
:25:42. > :25:46.is on its first visit to the inner solar system and it is bright now.
:25:46. > :25:52.We can't predict comets, they are like cats, they have tails and they
:25:52. > :25:56.are unpredictable. Fingers crossed. We don't know how .. Does that mean
:25:56. > :26:03.we are in danger of it breaking up? Do it is probably too big because
:26:03. > :26:06.it is so bright already and it is close to last. Because it is on its
:26:06. > :26:13.first week in, it has no track record and anything can happen.
:26:13. > :26:16.don't know if it has enough material that might create a tale.
:26:16. > :26:22.There are some spectacular -- spectacular fizzled, it's from the
:26:22. > :26:26.past. We had many questions. One young man said he was not able to
:26:26. > :26:34.sleep last night because he was worrying about this question. His
:26:34. > :26:42.name is Jamie from Hampshire. How you? Kenya hear asked? You were
:26:42. > :26:47.worried about one question. Ask our panel. Well, it could there be any
:26:48. > :26:55.other universes other than our own and if so could they be outside the
:26:55. > :27:02.laws of physics? Yes, I think is the answer. It is possible, as you
:27:02. > :27:06.go beyond our visible horizon, there could be many other universes.
:27:06. > :27:11.It is possible there could be other universes and the laws of physics
:27:11. > :27:14.could be local to how a Barbour. But within our bubble, with
:27:14. > :27:22.individual horizon, the laws of physics identical in this universe.
:27:23. > :27:27.But yes. But don't lose any sleep over it! There could well be. It is
:27:27. > :27:33.becoming a much more accepted model in cosmology that there are other
:27:33. > :27:38.universes. You could say the laws of physics in this universe
:27:38. > :27:42.appeared beautifully set up. What is the reason why? The reason could
:27:42. > :27:47.be that there are many universes and many different laws of physics
:27:47. > :27:52.and we live in the one where the laws of physics... If the universe
:27:52. > :28:00.is infinite, could there be a region of a universe there would
:28:00. > :28:06.have different laws of physics? think so. We are finding it hard to
:28:06. > :28:10.Test that idea. Yes, it could be, but how can we tested? A fantastic
:28:10. > :28:20.question, Jamie. I hope we have given you an answer that allows you
:28:20. > :28:20.
:28:20. > :28:27.to rest worry-free! Thank you. thought the most accurate was
:28:27. > :28:31.somebody saying it could be the Martian equivalent of the glacier.
:28:31. > :28:37.I will buy two points. We should say thank you to Jodrell Bank
:28:37. > :28:43.because every year wonderful hospitality and I am going to drink
:28:43. > :28:51.to Jodrell Bank! We have to thank so many of our panel. Go to the