Episode 1

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:00:18. > :00:26.The skies are clear, the stars are out and juptever -- Jupiter is

:00:26. > :00:36.shining in the sky. I'm Brian Cox. He's Dara O Briain and this is

:00:36. > :00:56.

:00:56. > :01:05.Welcome to a, well, slightly cold, but generally brilliantly clear,

:01:05. > :01:10.crisp evening here in Macclesfield. It's what you need, Jupiter shining

:01:10. > :01:16.crystal clear. It's beautiful. We're at the Jodrell Bank

:01:16. > :01:22.Observatory in Cheshire. This is one of the historic instruments of

:01:22. > :01:30.space exploration and astronomy. Here it is, 90 metres high, and 75

:01:30. > :01:37.metres in diameter. This was the only telescope of its time when it

:01:37. > :01:42.could detect Sputnik and it was used in the Apollo missions.

:01:42. > :01:48.back, relax and be amazed by what is above your heads. Over the next

:01:48. > :01:51.three nights we're going to be exploring the universe, looking at

:01:51. > :01:58.everything from the most distant stars and galaxies to our closest

:01:58. > :02:02.neighbour, the moon. We'll tackle the big questions like how do you

:02:02. > :02:08.find new planets outside of our solar system, and what would we say

:02:08. > :02:12.if we actually made contact with aliens? And there will be some very

:02:12. > :02:21.special guests, starting tonight with the last man to walk on the

:02:22. > :02:27.moon, Captain Eugene Cernan. And we're asking you to help find a

:02:27. > :02:33.planet. And we want you to turn off all the lights in this town, live

:02:33. > :02:38.on air. And we'll be showing you what kit you need to get started in

:02:38. > :02:44.star gazing. And we'll tell you what to see over the next three

:02:44. > :02:50.nights. Talking to Captain Eugene certainon. The Apollo missions are

:02:50. > :02:55.the greatest achievements in history. They just are. We've not

:02:55. > :03:01.even had a debate, don't e-mail in. You'll get no short change, they

:03:01. > :03:07.are. And we're talking to the last man on the moon. I can't wait.

:03:07. > :03:12.want to hear your questions for the Captain. E-mail them to us, or

:03:12. > :03:21.tweet. Jodrell Bank remains one of the

:03:21. > :03:26.most act ive astronomical research centres in the universe. This is a

:03:26. > :03:32.working observatory and Dr Tim O'Brien has joined us again. If you

:03:32. > :03:39.remember him from last year. And this telescope is working now.

:03:39. > :03:47.looking at an object somewhere over there about 4,500 light years away

:03:47. > :03:54.and rejoices in the name PO88 minus 1. What it is? It's the remains of

:03:54. > :03:58.a star that exploded some years go and as it spins it producers radio

:03:58. > :04:07.waves that have been travelling for thousands of years and are being

:04:07. > :04:11.picked up by that telescope. Now, you don't need a telescope like

:04:11. > :04:21.this to appreciate the night sky, there is plenty to see as Mark will

:04:21. > :04:26.show us now. I'm here with the members of the South Cheshire and

:04:26. > :04:32.Macclesfield astronomy group. We have a great group of people from

:04:32. > :04:37.beginners to experience people and people who have no equipment at all

:04:37. > :04:42.through binoculars and computers and telescopes with complex drive

:04:42. > :04:51.systems. The skies are still clear and we had fantastic views of Venus

:04:51. > :04:55.as it was setting in the west. And behind me we have Orion in the top,

:04:55. > :05:00.left corner. Hopefully the skies will stay clear. Check back later

:05:01. > :05:07.and we'll let you know how we're getting on. And the final member of

:05:07. > :05:14.our team, Liz Bonnin has travelled all the way to South Africa for us.

:05:14. > :05:19.But it's not as clear as this. love that. We were surrounded by

:05:19. > :05:25.rip-roaring storms later on, but thankfully they have appeased. We

:05:25. > :05:32.are here because of that. The Southern African Large Telescope,

:05:32. > :05:38.or SALT. We are operating on specialist star-light cameras so we

:05:38. > :05:44.don't interfere with their work. But you don't need a telescope like

:05:44. > :05:49.that to observe these beautiful skies. We used this telescope to

:05:49. > :05:55.get these pictures. Incredible images of the moon there. The moon

:05:55. > :05:59.is the only place that we have ever set foot apart from earth. And

:05:59. > :06:05.although it is familiar in our night sky it remains the most

:06:05. > :06:10.fascinating. The moon has been our closest

:06:10. > :06:15.celestial companion for almost the whole of our planet's history. But

:06:15. > :06:22.we've always speculated about where it came from and what it is made of.

:06:22. > :06:25.The moon started when the Earth was just a huge lump of rock and iron

:06:25. > :06:31.4.5 billion years ago. The environment in which the early

:06:31. > :06:36.earth existed was chaotic. In all that confusion it was hit by a

:06:36. > :06:40.smaller, rocky world. The collision almost broke both planets apart,

:06:40. > :06:46.but instead the two bodies began to merge.

:06:46. > :06:50.Some debris from the impact was flung into orbit around the earth.

:06:50. > :06:55.Gravity caused this mostly rocky material to come together, forming

:06:55. > :07:01.our moon. Back then, it was much closer to our world and would have

:07:01. > :07:06.looked spectacular, cooling on the horizon, the hot surface of earth.

:07:06. > :07:12.Over the next two billion years the earth and the moon exerted their

:07:12. > :07:17.gavtationial forces on each other. The rotation of the earth slowed.

:07:17. > :07:24.The moon's orbital speed stkreefed and it moved away from us. It now

:07:24. > :07:31.takes just over 37 days for it to orbit the earth. And today it is

:07:31. > :07:35.225,000 miles away. It is still drifting away at a rate of 3.87

:07:35. > :07:40.centimetres per year. When it is fool, the moon is the brightest

:07:40. > :07:46.thing in the night sky but through the month, its relation to the

:07:46. > :07:51.earth changes and we witness the shadow of lunar night-time passing

:07:51. > :07:56.over the surface. When it is in complete shadow, it is called a new

:07:56. > :08:02.moon. These different appearances are called the phases of the moon.

:08:02. > :08:07.Whenever we look up at it, we always see the same side staring

:08:07. > :08:14.back at us. Not surprisingly, astronomers have speculated about

:08:14. > :08:22.what the far side was like. We never saw it until a Russian probe

:08:22. > :08:28.went round the far side in 19 59. These are the images it sent back,

:08:28. > :08:34.rough and grainy, less than ten years later, the Apollo astronauts

:08:34. > :08:41.were the first to see the far side of the moon with the naked eye.

:08:41. > :08:45.They witnessed a cratered landscape. In the beginning God created the

:08:46. > :08:51.heaven and the earth and the earth was without form and void. Less

:08:51. > :08:57.than a year later, Neil Armstrong and Buzz Aldrin took their first

:08:57. > :09:02.steps on the moon. One small step for man, one giant leap for mankind.

:09:02. > :09:07.There's no atmosphere to speak of there and the gravity is one sixth

:09:07. > :09:13.of the earth so the heavy space suits weighed less making it easy

:09:13. > :09:20.for them to bounce around on the moon's surface. When the rock

:09:20. > :09:27.samples were studied they were found to contain minute rals like

:09:27. > :09:33.magnesium, iron and iron. The temperature is 133 degrees

:09:33. > :09:40.centigrade. But some craters contain permanently shadowed

:09:40. > :09:45.regions that have not seen sunlight for billions as year and can get so

:09:45. > :09:49.cold that they are the coldest places in the solar system we know

:09:49. > :09:53.of. Most of our knowledge of the moon has been gained in the last 50

:09:53. > :09:59.years and we're still learning. Just two years ago, we discovered

:09:59. > :10:06.traces of water, frozen in the lunar soil. An intriguing discovery

:10:06. > :10:12.that adds to the mystery of our closest neighbour.

:10:12. > :10:17.Now, those of you watching last year will remember we had this high

:10:17. > :10:24.tech touch screen. No-one believed it was real. So we traded it in and

:10:24. > :10:28.we have this one, controlled by this. So if I press that...there we

:10:28. > :10:32.are! There we G I want to talk a little bit about current research

:10:32. > :10:36.into the moon. This is the face of the moon that we're all familiar

:10:36. > :10:41.with. You see the seas and the craters. And there are big

:10:41. > :10:49.questions about how the moon evolved and why it looks the way it

:10:49. > :10:58.does. We know these maria or seas are volcanic. They're a new surface

:10:58. > :11:01.so they're younger than the craters. And some of the uplands are higher

:11:01. > :11:07.than Everest. It's a remarkable feature. And there's a contrast

:11:07. > :11:11.with the side we don't see. This is the so-called dark side. But it

:11:12. > :11:16.isn't dark, it's just away from us. And that's completely different.

:11:16. > :11:20.You don't see the seas. And there's a new therapy, well, the old theory

:11:20. > :11:25.is that the moon formed in some kind of collision. But the new

:11:25. > :11:31.theory is that there was another collision with another moon. So

:11:31. > :11:35.four billion years ago, the earth had two moons and there was another

:11:35. > :11:39.collision. So you're seeing the debris of one moon on one or the

:11:39. > :11:49.other side. Yes, and that's a new theory. There is a video I want to

:11:49. > :11:55.show you. This is current research. We're still sending probes up, like

:11:55. > :11:59.the lunar reconnaissance. And this is from that now. This is only 600

:11:59. > :12:06.metres across. So you're seeing structure on the moon, things just

:12:06. > :12:11.a few metres across. A question we're asked a lot is could we see

:12:11. > :12:17.from earth through any kind of telescope the debris left behind by

:12:17. > :12:26.the Apollo missions? The answer is know. These are the landing sites

:12:26. > :12:31.of the Apollo missions. That is where Eugene certainon landed, you

:12:31. > :12:36.can't see that from the earth. You'd need a telescope the size of

:12:36. > :12:44.Manchester. But you can see it from the probe. This is a picture of the

:12:44. > :12:51.Apollo XI landing site. And what is interesting is how much more

:12:51. > :12:59.confident they were with time about staying on the moon. That is the

:12:59. > :13:07.footprint, just a few months ago, a picture of a foot print from Apollo

:13:07. > :13:13.14. 40 years ago! And this is remarkable. That is the moon buggy.

:13:13. > :13:20.The lunar rover and Challenger, Captain certainon's spacecraft. The

:13:20. > :13:27.bottom of it, the bit that didn't move off. Why did they park there

:13:27. > :13:31.and walk off. Is there a reason for that? I think we should ask him.

:13:31. > :13:37.And they have not eroded because there's no atmosphere. No wind or

:13:37. > :13:41.rain to erode them. That's right. It's a fossil. It's deep frozen.

:13:41. > :13:47.The formation of our solar system is written there and has been for

:13:47. > :13:55.billions of years. We can't tell you how proud we are, joining us

:13:55. > :13:58.live, from Houston in Texas, the Commander of Apollo 17, Captain

:13:58. > :14:03.Eugene certainon. Thank you very much for joining us. It's a

:14:03. > :14:08.pleasure to be with you. I'm just disappointed that I'm not with you.

:14:08. > :14:13.The description of the moon and what you're seeing there has to be

:14:14. > :14:19.unbelievable and I'm very proud to be with you today. Thank you very

:14:19. > :14:23.much. We're talking about 1961 when Kennedy made that speech" we choose

:14:23. > :14:29.to go to the moon" and he set America on a path to the moon

:14:29. > :14:32.within ten years. And you joined NASA in 1963. When you heard that

:14:32. > :14:38.visionon for American space exploration, did you immediately

:14:38. > :14:48.think, "I will apply to the astronaut programme?" Those were

:14:48. > :14:50.

:14:50. > :14:54.the days. The space speech SF Kennedy gave was about three weeks

:14:54. > :15:02.after there was the first flight. I wasn't even in the space programme.

:15:02. > :15:08.I was just a young, naval aviator and I kept thinking, "By the time I

:15:08. > :15:12.get good enough it will all be done" but the President himself was

:15:12. > :15:18.asking us to do what most thought couldn't be done, to do was most

:15:18. > :15:25.thought was probably impossible, go to the moon. I mean, think about

:15:25. > :15:30.that. We were not too many years after Sputnik. The earth was

:15:30. > :15:34.orbited about a month earlier and just put yourself back in into

:15:34. > :15:40.environment. It was an incredible challenge to mankind at that point

:15:40. > :15:46.in time, and particularly to the American people to even think about

:15:46. > :15:52.doing it. Can I ask about one trip you made before Apollo 17. You were

:15:52. > :15:56.on Apollo 10, because the whole programme advanced in successful

:15:56. > :16:01.steps and in Apollo 10 you took the lander within eight miles of

:16:02. > :16:09.landing on the moon and then came back again. What was that like?

:16:09. > :16:14.Well, you know, we were the second flight to ever go to the moon.

:16:14. > :16:21.Apollo 8 were the first human beings who left the confines of

:16:21. > :16:27.Earth to circle and orbit another planet. Well, I call the moon

:16:27. > :16:31.another planet so I take some licence. We were going to take the

:16:31. > :16:36.lunar module, the vehicle that was eventually going to take us down,

:16:36. > :16:41.and by the way, there was much talk that if we put ourselves in harm's

:16:41. > :16:47.way and go all that distance, maybe we ought to go all the way down.

:16:47. > :16:53.The decision was made "let's do everything but land" we painted a

:16:53. > :16:58.white line in the sky so the next lot wouldn't have to get lost and

:16:58. > :17:02.all they had to do was cover the last eight miles. But it was an

:17:02. > :17:07.incredible experience for me. I had no idea I would have a chance to go

:17:07. > :17:12.back. But just being a quarter of a million miles from home and here I

:17:12. > :17:19.was flying in and out of the shadows of another body out there

:17:20. > :17:26.in this universe of others. It was 200 light years and to be able just

:17:26. > :17:31.to look back at the Earth is a memory, I think, most of us can

:17:31. > :17:36.never forget. And Captain certainon, just under two years later you

:17:36. > :17:45.spent three days on the moon. How was that and what did you feel when

:17:45. > :17:49.you left the moon? The last man to stand on the moon, so far? Well,

:17:49. > :17:55.somewhat nostalgic, obviously. And those pictures you've been looking

:17:55. > :18:01.at are phenomenal. For me, it's the first time I've seen where we ent

:18:01. > :18:08.went, from that point of view, when I saw those pictures and I saw the

:18:08. > :18:15.tracks and where we walked. And I know exactly where I parked the

:18:15. > :18:21.lunar module because I put it there specifically so the television

:18:21. > :18:27.camera could get a picture of our lift off. Somebody asked, "Do you

:18:27. > :18:32.know what direction you pointed the front wheels?" and I said, "I think

:18:32. > :18:37.I pointed them a little to the left" and he said, "You're right."

:18:37. > :18:42.I don't know how you can see that from here, it's phenomenal. But I

:18:42. > :18:47.guess someone will go back and survey those sites and get a better

:18:47. > :18:52.picture than now. But it was mixed feelings. We'd come all that way.

:18:52. > :18:57.We wanted to stay longer. We knew we couldn't. We knew we were part

:18:57. > :19:03.of something significantly bigger than us, a great technologyy

:19:03. > :19:08.adventure. But here we are, half a century later and I still wonder

:19:08. > :19:13.what it means and what will it mean in the future? We will come back to

:19:13. > :19:17.you and we will talk about the future of space travel. Thank you

:19:17. > :19:24.very much for joining us for now. Now we're going back into the field

:19:24. > :19:33.to see what is right now. The skies are still clear for us.

:19:33. > :19:39.We have the constellations shining brightly over head. Gemini is

:19:39. > :19:46.shining brightly. And castor and poll yock are there. The guys have

:19:46. > :19:50.been picking up crazy things through the telescope. We've seen

:19:50. > :19:54.M31, the most distant object you can see with the naked eye. We're

:19:54. > :19:58.just keeping our fingers crossed that the skies will remain clear.

:19:58. > :20:03.Last year you sent thousands and thousands of photographs in and we

:20:03. > :20:08.want you to do the same this year, but we want to show you a few

:20:08. > :20:13.you've already sent in. If you want to send them in go to the website,

:20:13. > :20:17.bbc.co.uk/stargazing. Let's see a couple that we've seen

:20:17. > :20:26.because they are genuinely spectacular.

:20:26. > :20:29.This is remarkable. This is M42 and M43. It looks like a genuine

:20:29. > :20:36.professional photograph taken through a big telescope. This is

:20:36. > :20:46.what is happening above the skies in Wigan right now. These are star

:20:46. > :20:47.

:20:47. > :20:57.formations in Orion. Clouds of dust and gas? Will they event coaless

:20:57. > :20:57.

:20:57. > :21:02.into stars? Yes. This is from Mike in Swindon. OK, we'll be getting

:21:02. > :21:07.more as the show goes on and go on to the website if you want to join

:21:07. > :21:13.in the generally discussion about it. Take a look at this. This is

:21:13. > :21:18.what the full moon looks like in this country. The picture of the

:21:18. > :21:24.left. And on the right the moon was taken from South Africa last night.

:21:24. > :21:34.What is the difference? Obviously they are the other way round and

:21:34. > :21:35.

:21:35. > :21:40.Liz will explain. Thank you very much. I'm inside. More on that

:21:40. > :21:46.fantastic mirror later on. Now, imagine my face is the moon, no

:21:46. > :21:54.jokes please. If you stand on the northern hemisphere you're going to

:21:54. > :22:02.see me the right way up, but if I'm on the Southern hemisphere you'll

:22:02. > :22:08.see me upside down. It's not difficult. Last night I was

:22:08. > :22:17.watching the stars with somebody who has been studying the skies for

:22:17. > :22:23.ever ten years. Petris, we get a fantastic view of the Milky Way

:22:23. > :22:29.down here what else can't we see from the Northern hemisphere?

:22:29. > :22:39.Southern Cross. Four bright stars within the plain of the Milky Way

:22:39. > :22:46.

:22:46. > :22:51.ever there. And close by are alpha Centauri; And where Now, how do you

:22:51. > :22:55.navigate in the Southern hemisphere? Yes, there is no

:22:55. > :23:01.Southern Cross. But you do it by taking the long diagonal of the

:23:01. > :23:06.cross and follow the line through the sky and take a pointer

:23:06. > :23:16.perpendicular to them and where the lines cross, that is exactly where

:23:16. > :23:19.

:23:19. > :23:28.the South Pole is. And what else can we see down here? OmegaCentarri.

:23:28. > :23:34.It's a cluster of stars, many of them just outside the Milky Way.

:23:34. > :23:39.10,000 light years away. How many stars in that cluster? About 10

:23:39. > :23:46.million and it's the brightest of the clusters associated with the

:23:46. > :23:56.Milky Way. And one of the things I was looking forward to see with my

:23:56. > :24:03.

:24:03. > :24:10.own eyes are the imagine lenic clouds. That is the -- --

:24:10. > :24:14.magellanic clouds. That is the pack pap of them there. And that is the

:24:14. > :24:19.tarantula nebular taken by this telescope in the Karoo Desert.

:24:19. > :24:27.We'll find out more tomorrow but come back to me tonight to find out

:24:27. > :24:33.how that mirror works. Now, there's a slight twist in this, we keep

:24:33. > :24:40.telling you, look at the moon. But there is no moon out yet. No, the

:24:40. > :24:47.moon doesn't rise until 2am. So we want people to enjoy it after the

:24:47. > :24:52.show. What are you looking at now? This is the Orion Nablus. Stars are

:24:52. > :25:00.forming. Look at that cloud of gas. You can really see it. Yes, you can

:25:00. > :25:07.see the glowing gas. And the greater the telescope the more

:25:07. > :25:14.detail you'll see. Let me introduce you to Helen. Hello. Helen, how

:25:14. > :25:18.long have you been interested in astronomy? Well, I got a telescope

:25:18. > :25:22.for Christmas and I've always been interested, but I wanted to see it

:25:22. > :25:27.with a bigger eye, hence the telescope. And it's only a few

:25:27. > :25:33.months you've been interested in it? Well, a few weeks, because it

:25:33. > :25:38.was Christmas. But I've learnt so much tonight. And what have you

:25:38. > :25:42.seen? The lines around Jupiter. And the other day I saw the moon and

:25:42. > :25:48.the craters, which was amazing. All of it is very, very exciting.

:25:48. > :25:54.you're enjoying it? I love it. year, we were asked what kind of

:25:54. > :25:59.equipment you need to get into astronomy. So we've put together a

:25:59. > :26:03.guide and what better place to start that where Captain certainon

:26:03. > :26:08.went to 40 years ago. The moon is a constant presence.

:26:08. > :26:14.It's close to the earth but visible nearly every day. While stars and

:26:14. > :26:18.planets come and go, our closest neighbour is with us throughout the

:26:18. > :26:22.year. These characteristics mean the moon is a fantastic object to

:26:22. > :26:28.focus on if you want to learn more about looking at the night sky. And

:26:28. > :26:33.the great thing is that observing the moon is really easy to do. Even

:26:33. > :26:38.just using your naked eye you can pick out markings on the moon's

:26:38. > :26:43.surface. And if you're inspired to take a closer look, it won't break

:26:43. > :26:48.the bank. You can even try it from your own back garden.

:26:48. > :26:55.A great way to begin observing the night sky is through a pair of

:26:55. > :27:02.binoculars. You can use any pair, but these are good for astronomy.

:27:02. > :27:08.They're known as 15X70. Which means they magnify 15 times and the lens

:27:08. > :27:15.is 70mm across. And I have them on a tripod to keep them steady. A

:27:15. > :27:18.zefpbt pair of binoculars will cost �30. You can find craters along the

:27:19. > :27:23.line of shadow between light and dark.

:27:23. > :27:26.And see the Sea of Tranquillity where the first men to land on the

:27:26. > :27:32.moon touched down. But that's just the be beginning.

:27:32. > :27:36.If you find yourself getting hooked, you might want to try using a

:27:36. > :27:42.telescope. I remember the first time I looked luing a telescope. I

:27:42. > :27:47.was ten years old and I was blown away by what I saw. And no matter

:27:47. > :27:55.how many pictures of space you look at, there's nothing that quite

:27:55. > :28:01.beats seeing it with your own eyes. The telescope will allow you to

:28:01. > :28:06.explore great, flat lunar plains at the top of the moon and mountain

:28:06. > :28:11.regions running between them. The surface appears to ripple because

:28:11. > :28:17.we're looking through the earth's atmosphere. You can see a rugged

:28:17. > :28:26.landscape marked by thousands of impacts over billions of years.

:28:26. > :28:34.Optical telescopes come in a range of sizes. A good amateur one costs

:28:34. > :28:42.between �150 and �300. The wider the apature the more you'll be able

:28:42. > :28:48.to see. A good starting apature is between three and six inches. And

:28:48. > :28:51.how much a telescope will magnify an object is determined by the

:28:51. > :29:01.length of the telescope and the length of the eye piece, which

:29:01. > :29:02.

:29:02. > :29:08.slots into the telescope. This is a crater known as

:29:08. > :29:16.Copernicus which has been magnified around 50 times and this is it with

:29:16. > :29:20.100 times mag fiction.Le it is the same telescope, but a more powerful

:29:20. > :29:24.eye piece. There are two basic types of telescope and which one

:29:24. > :29:30.you want depends partly on what you want to see. If you want to get the

:29:30. > :29:37.best view of bright objects, like the parents and the moon then a

:29:37. > :29:41.telescope with a refractor in it could be best for you, and you look

:29:41. > :29:51.along the tufpblt but if you're particular interested in looking

:29:51. > :29:54.

:29:54. > :29:58.for faint objects, like galaxies or nebulae, you need a reflective

:29:58. > :30:02.telescope. And you look through a tube at the top because you're

:30:02. > :30:11.looking at reflected light through the mirror. Both types will give

:30:11. > :30:16.you a good view, but reflecting telescopes tend to be big er. If

:30:16. > :30:25.you wanted really easy and you have more cash to spare, you might think

:30:25. > :30:32.about this. This is a kuperised telescope. They -- computerised

:30:32. > :30:38.telescope. They cost around �300 and if they are set up correctly

:30:39. > :30:44.they will get you looking at what you want. So if I want to look at

:30:45. > :30:52.Jupiter I set "Jupiter" into this hand set and the telescope will

:30:52. > :30:58.swing around to get a good view. The telescope is attached to this

:30:58. > :31:04.laptop computer. And there it is! Any good amateur telescope will

:31:04. > :31:13.allow you to explore the solar system with your own eyes. You can

:31:13. > :31:19.find the moons that orbit Jupiter. View the planet Saturn, with its

:31:19. > :31:25.icy rings. And even make out the red glow of one of the smallest

:31:25. > :31:31.planets, Mars. And the best thing is that it is a

:31:31. > :31:36.real, live view. With a bit of research and some patience, there's

:31:36. > :31:46.nothing that beats looking up and realising that what you can see

:31:46. > :31:47.

:31:47. > :31:53.really is there, hanging in space, millions of miles away.

:31:53. > :31:58.Now, one other thing to think about, of course, is telescope mounts. You

:31:58. > :32:03.need to make sure that whatever mount you get is solid because the

:32:03. > :32:10.telescope needs to be held firmly to get a good image. If you're not

:32:10. > :32:16.sure go to the shop and they'll be able to help you out. We've put a

:32:16. > :32:21.guide on the website. On the website you'll also be able

:32:21. > :32:29.to download this year's Starguide which has a whole section dedicated

:32:29. > :32:36.to the moon. And there will be the Open University's virtual

:32:36. > :32:46.microscope. And you'll see a video explaining some of the myths, like,

:32:46. > :32:56.

:32:56. > :33:01.how the moon turns men into werewolfs. Stop it!

:33:01. > :33:05.Bbc.co.uk/stargazing is where you G and we'll be back for more

:33:05. > :33:12.discussion in Stargazing Liveback to earth immediately after this

:33:12. > :33:19.show. What star sign are you? don't know. Now, this is not the

:33:19. > :33:28.biggest moon in the solar system. This is Jupiter and we are fairly

:33:28. > :33:35.sure that that point of light is Ganymeade which is bigger than the

:33:35. > :33:43.planet Mercury. If that is Ganymeade that could harbour life

:33:43. > :33:49.because it's so big and it has tidal influences so it may have a

:33:49. > :33:54.liquid ocean beneath its surface. That tells you about the magic of

:33:54. > :33:59.astronomy. Because our moon is so big in relation to the earth it has

:33:59. > :34:07.profound effects, not least in the way it controls the movements of

:34:07. > :34:12.our oceans. Have you ever wondered what causes

:34:12. > :34:17.the tides? Well, of course, it's got something to do with the moon

:34:17. > :34:24.but what exactly is it that causes the ocean to roll up the beach and

:34:24. > :34:30.roll back again twice a day? The tides are caused mainly by the

:34:30. > :34:38.gravitational pull of the moon. So here is the earth and here is the

:34:38. > :34:43.moon. Now, the gravitational force on any point on the earth depends

:34:43. > :34:46.on the distance between that point and the moon. That's Newton's law

:34:46. > :34:51.of gravity. Imagine the ocean surrounding the earth and take a

:34:51. > :35:00.point on the ocean. What you have to do to calculate the

:35:00. > :35:04.gravitational pull would be to work out what that distance is. Or say

:35:04. > :35:09.that point. It's further away from the moon so the gravitational pull

:35:09. > :35:13.of the moon will be less. So we have to calculate that distance. So

:35:13. > :35:17.you can see that the gravitational pull on the moon on the water

:35:17. > :35:24.changes depending on where you are. Both the direction changes and the

:35:24. > :35:29.strength of the pull. The up shot of all that is that the ocean gets

:35:29. > :35:33.deformed. The shape of the water gets pulled and squashed into a

:35:33. > :35:40.kind of rugby-ball shape. So you get a bulge of water facing the

:35:40. > :35:45.moon. And, because of the way the difference in gravitational pull

:35:45. > :35:50.works, you get a bulge of water on the opposite side of the earth to

:35:50. > :35:55.the moon and these bulges here, are the high tides. So, today, the moon

:35:55. > :36:00.is just over there, actually, somewhere close to the sun. So

:36:00. > :36:04.we're in this position, almost directly beneath the moon so that

:36:04. > :36:09.means we're beneath this tidal bulge and that is why on this beach,

:36:09. > :36:16.at this moment, there is a high tide. But what about a low tide?

:36:16. > :36:22.Why does the water go back out again? Well, the tide goes out

:36:22. > :36:27.because the earth is rotating. You see, at high tide then I am

:36:27. > :36:33.standing here, on the beach beneath the tidal bulge. And the moon is

:36:33. > :36:38.just positioned in the sky over there. But if I wait six hours,

:36:38. > :36:45.give or take a bit of movement of the moon, then the earth will have

:36:45. > :36:50.rotated. So this beach will have moved. I'll be stood here. That is

:36:50. > :36:56.low tide. So it's tempting to think that it's the water that is moving.

:36:56. > :37:01.You know, it's in the language, the sea is going out. Well, it's not

:37:01. > :37:06.the sea going out. The tidal bulge is in the same place, what is

:37:06. > :37:13.happening rather than the water going away from me, I am going away

:37:13. > :37:20.from it. Water is fluid, it moves and flows.

:37:20. > :37:27.So it's easy for the moon to distort the shape of our oceans.

:37:27. > :37:33.But the moon's gravity doesn't just pull on the oceans it pulls on our

:37:33. > :37:39.entire planet. Now, at high tide I'm next to that bulge of water.

:37:39. > :37:43.But I'm also on a bulge of solid rock. The whole earth is being

:37:43. > :37:47.stretched and squashed by the gravitational pull of the moon. So

:37:48. > :37:54.at the same time as the oceans, the whole earth is being stretched into

:37:54. > :37:59.a rugby-ball shape by the moon. But it's much harder for the moon to

:37:59. > :38:04.distort the shape of solid rock than water, so the distortion is

:38:04. > :38:09.tiny. We don't even realise it's happening. But it is a different

:38:09. > :38:15.story for the moon. Because just as the moon raises tides on the earth,

:38:15. > :38:19.the earth raises tides on the moon. Ever since it was first formed,

:38:20. > :38:25.over four billion years ago, the solid body of the moon has been

:38:25. > :38:30.skreched and squashed by the tidal forces of the earth. If I was able

:38:30. > :38:36.to stand on the lunar surface four billion years ago, and looking up

:38:36. > :38:41.at the earth, I would see a giant rock tide raised by the earth's

:38:41. > :38:45.gravity on the surface of the moon. It would have been about seven

:38:45. > :38:50.metres high. And as the moon rotated, that bulge of rock would

:38:50. > :38:55.sweep across the surface of the moon, just as the oceans sweep I

:38:55. > :38:59.cross the surface of our planet. So the earth raises that tidal bulge

:38:59. > :39:07.on the moon but because of the moon's rotation, that bulge is

:39:07. > :39:11.always slightly ahead of where the earth is. So that meant the earth's

:39:11. > :39:16.gravity acted like a brake. It pulled on the bulge to slow the

:39:16. > :39:22.rotation of the moon down. Now, over time, millions, billions of

:39:22. > :39:25.years, that meant that the moon's rotation rate slowed. And in turn,

:39:25. > :39:29.that meant that the moon drifted further and further away, until you

:39:30. > :39:35.get to the situation we have today, where the moon has slowed so much,

:39:35. > :39:43.the time it takes to complete one orbit is almost exactly the same as

:39:43. > :39:48.the time it takes to rotate once on its axis. So the moon's rotations

:39:48. > :39:54.have become sychronised so one face of the moon is always pointing to

:39:54. > :39:59.the earth and that's why we only see one face when we look up into

:39:59. > :40:03.the night's sky. Tides are caused but one of the

:40:03. > :40:09.fundamental forces of the universe, gravity. And they bend and stretch

:40:09. > :40:14.rocks as well as oceans. Tides distort the shape of our entire

:40:14. > :40:18.planet and they've slowed down the rotation of our moon. So tides are

:40:18. > :40:22.much more than just the gentle roll of water up and down the beaches of

:40:22. > :40:31.the world. Now you can see the effects of tides all over the solar

:40:31. > :40:41.system. In 1979, the Voyager spacecraft showed graphically the

:40:41. > :40:42.

:40:42. > :40:49.power of tides. This is the inner of the moons of Jupiter, called Io,

:40:49. > :40:55.and it's the most volcanic place in the solar system. So it's not like

:40:55. > :41:04.a volcano we would have on earth. It's not molten rock bursting

:41:04. > :41:10.through the surface? No, but it is molten rock. And Io is maintained

:41:10. > :41:15.in an elliptical orbit around the other planets, it passes close to

:41:15. > :41:22.the planet and far away, close and far away, and that means it gets

:41:22. > :41:28.skreched and squashed and heated by the immense fors of Jupiter and Io

:41:28. > :41:34.can turn itself inside out. So its rocks are constantly spilling out

:41:34. > :41:41.on to the surface. Yes, and it's kept in orbit by the interaction of

:41:41. > :41:46.the other moons. It's so complex but it shows the power of tides.

:41:46. > :41:52.We've had a number of questions coming through. Shaun in Tipperary

:41:52. > :41:55.asks why is the moon slowly moving away from earth. In physicals

:41:55. > :42:02.language it's called the conservation of angular momentum.

:42:02. > :42:07.The reason is because there's a fixed amount of speed in the

:42:07. > :42:11.earth's-moon system. And, as we spoke about in the film, the moon

:42:11. > :42:18.is slowing down and the spin has to go somewhere, so the moon moves

:42:18. > :42:25.further away and that takes the spin that is lost. And why does the

:42:25. > :42:31.moon look like it's made from uniform dusty rock, while the earth

:42:31. > :42:36.is made from red rock and yellow rock, et cetera. Well, the red is

:42:36. > :42:43.caused by rust, so you need atmosphere. And there's no oxygen,

:42:43. > :42:50.so it's unchanging. That's it. And the oxygen in our atmosphere came

:42:50. > :42:55.from life. It isn't there naturally. Now, Liz is in South Africa, which

:42:55. > :43:00.has one of the finest collection of telescopes.

:43:00. > :43:06.I'm still inside the SALT telescope and tonight, light from millions of

:43:06. > :43:12.light years away will be filtering down on to this mirror. Downstairs

:43:12. > :43:18.astronomers are gearing up for a night of star gazing. But how did

:43:18. > :43:24.the telescope end up in the middle of the desert and what is it

:43:24. > :43:30.looking at? This is where modern astronomy began in South Africa.

:43:30. > :43:36.The first Royal Observatory was built in Cape Town in 1820 and for

:43:36. > :43:42.the next 150 years it's where stargazers from all over Africa

:43:42. > :43:47.came for the best view of the night sky. But eventually the night sky

:43:47. > :43:53.got drowned out by the cities and they had to look for somewhere more

:43:53. > :44:00.remote. And it doesn't get much more remote than this. Over 200

:44:00. > :44:05.miles north-east of Cape Town, the Karoo Desert is one of the most

:44:05. > :44:11.inhospitable places in Africa, but almost a mile above sea level and

:44:11. > :44:19.with unpolluted skies it is almost the perfect place for an

:44:19. > :44:24.observatory. That is why hundreds of people come here. It is a global

:44:24. > :44:30.operation. Astronomers from all over the world use the ISS

:44:30. > :44:39.telescope. They peer through the Milky Way to gain a new view of our

:44:39. > :44:46.galaxy. These telescopes are run from Poland and they're looking for

:44:46. > :44:52.planets outside of our solar system. This extremely little telescope run

:44:52. > :44:57.by America surveyed large parts of the sky, and it is quite possibly

:44:57. > :45:02.the smallest professional telescope in the world. This is the 1.9m

:45:02. > :45:06.telescope, a pineer is helping us to understand the centre of our

:45:06. > :45:11.galaxy. At one point this was the largest telescope in the Southern

:45:11. > :45:16.hemisphere. But now...they've got this.

:45:16. > :45:23.A telescope with the ability to look much deeper into our universe.

:45:23. > :45:29.One of the biggest telescopes on earth the Southern African Large

:45:29. > :45:36.Telescope or SALT. David Buckley is in charge of what has been

:45:36. > :45:44.nicknamed Africa's giant eye. the largest telescope in the

:45:44. > :45:50.Southern hepls fare. It consists of 91 mirrors held in precise

:45:50. > :45:54.alignment it allows us to look at objects one billion times fainter

:45:54. > :46:01.than you can detect with the human eye. That means you can look at

:46:01. > :46:08.objects on the very edge of the universe. The very first things to

:46:08. > :46:12.emerge after the Big Bang. So how do you analyse it? We have a fancy

:46:12. > :46:18.digital camera that takes a picture of a part of the sky. For example,

:46:18. > :46:22.this is an image of what is called a Gamma Ray Burst. That is a very

:46:22. > :46:27.distant energetic object that suddenly exploded. Looking at that

:46:27. > :46:35.image on its own tells you have little, but when you disperse the

:46:35. > :46:43.light with a spectrograph you get this sort of picture and this tells

:46:43. > :46:48.me immediately that this is a very distant galaxy and the spectrum

:46:48. > :46:55.tells us what is absorbing the light between it and us and how

:46:55. > :47:00.fast it is moving. So you need a great camera and something that

:47:00. > :47:07.splits up the light to learn more about the properties of the object?

:47:07. > :47:13.Indeed. What are you looking at now? Everything from the closest

:47:13. > :47:17.objects, near-earth objects, which are asteroids that possibly could

:47:17. > :47:23.threaten the earth in the future. We're even discovering planets

:47:23. > :47:28.around other stars. And the nearest neighbouring galaxies to the Milky

:47:28. > :47:34.Way, so the magellanic clouds. They're particularly interesting.

:47:34. > :47:41.There is just a whole zoo of different types of galaxies that

:47:41. > :47:46.interest astronomers in many different ways.

:47:46. > :47:51.And that huge mirror is above us. This is the control room where all

:47:52. > :47:57.that light is processed. David, you observe the night skies for many

:47:57. > :48:04.institutions all over the planet, is that right? That's right. We

:48:04. > :48:11.observe ten proposals a night. are you looking at tonight and for

:48:11. > :48:16.whom? Tonight we're looking at one of the distant galaxies that formed

:48:16. > :48:22.after the Big Bang and that's for The University of Nottingham.

:48:22. > :48:27.That's great. And you take images of all sorts of things. This is

:48:27. > :48:34.beautiful. This is the lagoon Nablus and it's a big cloud of gas

:48:34. > :48:39.in our Milky Way which is embedded with hot stars which have a lot of

:48:39. > :48:47.ultraviolent light which cause all that colouration. And this is the

:48:47. > :48:52.other end of the spectrum. Some stars go through a period in which

:48:52. > :48:58.they expel a huge amount of their material into a sort of shell but

:48:58. > :49:05.the whole star doesn't disintegrate. In the centre of the Nablus is the

:49:05. > :49:15.object. Is that the dwarf star? a compact object like a dwarf star.

:49:15. > :49:17.

:49:17. > :49:24.And what is this? This is NGC 1365. A snappy name! It has a spiral very

:49:24. > :49:28.similar to our Milky Way galaxy. Fantastic. And we'll be talking

:49:28. > :49:36.about galaxies tomorrow night. I will see you then. Thank you very

:49:36. > :49:41.much. And I'm delighted to say that Captain certainon is still with us.

:49:41. > :49:45.You referred to you earlier on as the last man to walk on the moon

:49:45. > :49:51.and that was 40 years later. Are you disappointed that you are still

:49:51. > :49:58.the last man to walk on the moon? Well, I'd like to think of myself

:49:58. > :50:03.as the last man of the 20th century. We're going to go back, curiosity

:50:03. > :50:07.will take us. I'm listening to your show and I'm trying to visualise

:50:07. > :50:12.what you're saying, and the universe is so full of things we

:50:12. > :50:16.want to know something about and, you know, going back to the moon is

:50:16. > :50:23.just the first next step. I think we'll go from there without

:50:23. > :50:29.question, tomorrow. So we ask ourselves who are we? Where are we?

:50:29. > :50:34.Where did we come from? How did we get here? Is there life in outer

:50:34. > :50:38.space? And you could find life as we know it, or maybe there's some

:50:38. > :50:42.other definition of life, I do not know. But there is no question that

:50:42. > :50:50.mankind will continue to explore and move out of his universe. And

:50:50. > :50:59.there's no end, from my point of view, so this could go on for ever,

:51:00. > :51:09.how ever long forever is. There was a confirmation last year called the

:51:09. > :51:18.1hunhunyaer starship confirmation. And the -- 100 year star stip

:51:18. > :51:23.conference. So what can we do to make human society come together to

:51:23. > :51:28.make those grand leaps into the unknown, in the way that building a

:51:28. > :51:33.cathedral was 1,000 years ago? know, if you look back at what

:51:33. > :51:41.space has done, it has brought human society as we know it here on

:51:41. > :51:46.earth much closer together. I mean, we can share everything, like

:51:46. > :51:50.athletic events so disasters that occur on this earth almost

:51:50. > :51:57.instantaneous. We can share the enjoyment and the challenge already.

:51:57. > :52:04.And we will go to Mars and where we go, I think it will certainly be an

:52:04. > :52:10.international adventure, with a combination of our intelligent, our

:52:10. > :52:15.capabilities put together in one pot and that's just the very next

:52:15. > :52:20."near step" it might be a generation away, but that's not

:52:20. > :52:24.that far. We've had questions from viewers coming in. And this one

:52:24. > :52:30.says, "When I go to start my car in the morning, there's always a

:52:30. > :52:35.moment when I think it's not going to start. Did Captain certainon

:52:35. > :52:41.have any thoughts like that when he was on the moon?" That's a good

:52:41. > :52:45.question. I grew up in Chicago where the weather gets pretty cold

:52:45. > :52:49.and you go to start the car in the morning and you're not sure it will

:52:49. > :52:55.turn over. You know, if you worry about that, you worry about it

:52:55. > :53:01.before and if it really bothers you, you don't G but once you're there,

:53:01. > :53:07.you've bit the bullet. Enjoy it, enjoy the three days, make the most

:53:07. > :53:11.of it and get as much done as you can, and of course we'd built

:53:11. > :53:17.redundancy into the spacecraft and there's only one engine and things

:53:17. > :53:24.have to work right. I never, ever went to the moon not to come home.

:53:24. > :53:29.Did I ever think about it? Yes. But what would I have done if when you

:53:29. > :53:35.turn the key it didn't start, frankly, I don't know and I'm glad

:53:35. > :53:41.I didn't have to answer that question. We've run out of time,

:53:41. > :53:48.but it's been a pleasure to talk to you. 2457 you very much for joining

:53:48. > :53:53.Well, it's a pleasure. I really feel like I missed the best part of

:53:53. > :53:57.the show by not being there with you because I was listening and I'm

:53:57. > :54:01.fascinated by what you're talking about. The element of time in our

:54:01. > :54:07.lack of understanding of time is so important to what we see out there.

:54:07. > :54:12.So, you know, open it up to these young kids. Inspire them to dream

:54:12. > :54:19.the impossible and the impossible will happen. Thank you very much,

:54:19. > :54:27.Captain Eugene certainon joining us from Texas. How is it holding up

:54:27. > :54:32.outside here? High I'm here with Andrew Green who is the Chair of

:54:32. > :54:35.the astronomy society. What do you get out of the society? It's just

:54:35. > :54:40.great to bring lots of people together under the stars and the

:54:40. > :54:44.planets, as we're doing now and just experience the camaraderie.

:54:44. > :54:51.It's exciting, enjoyable. Just get out there and do it. And you can

:54:51. > :54:57.learn so much from each other. We've seen some brilliant sights in

:54:57. > :55:02.the skies tonight and if you want to know what is going on, tune into

:55:02. > :55:09.the show that follows immediately after this, and I have some special

:55:09. > :55:13.guides for what to look out on. But, as always, it's reliant on whether

:55:13. > :55:17.as always, it's reliant on whether we get clear skies. So here's the

:55:17. > :55:21.weather Thank you very much. It's pretty clear out there, country-

:55:21. > :55:26.wide at the moment. I'm going to show you the picture from space

:55:26. > :55:30.down to the UK this afternoon. It shows largely clear skies, however,

:55:30. > :55:34.this line of white is cloud spilling into parts of Northern

:55:34. > :55:41.Ireland and western Scotland so here conditions are far from

:55:41. > :55:47.perfect. But across the bulk of England, Wales and much of skhral

:55:47. > :55:51.Scotland there are clear -- central Scotland there are clear skies. But

:55:51. > :55:57.that means it's also pretty cold right now. So if you are heading

:55:57. > :56:00.out after the show, put some layers on. Tomorrow night is nowhere near

:56:00. > :56:05.as cold, but unfortunately that is because there will be much more

:56:05. > :56:12.cloud in the sky. Eastern areas could have clear skies for a time,

:56:13. > :56:18.but overall, exact it to be cloudy. And that blue means rain. Perfect

:56:18. > :56:23.conditions tonight, though. Thanks, Alex. Now, as we mentioned

:56:23. > :56:29.at the start of the show, this year we want to try something very

:56:29. > :56:35.special indeed. With your help we want to try and find our own exo-

:56:35. > :56:43.planet, that's a planet around a distant star. To do this, we've

:56:43. > :56:53.joined up with the Planet Hunters joined up with the Planet Hunters

:56:53. > :56:55.

:56:55. > :57:02.project. What are you trying to do? We have to look at the brightness

:57:02. > :57:10.of stars down to earth and we look at the data and look at the tiny

:57:10. > :57:17.dips in the brightness when a planet goes in front of its star.

:57:17. > :57:23.The obvious question is why are we doing it? Computers have a stab at

:57:23. > :57:31.this data. But we know humans can find things computers can. We're

:57:31. > :57:37.good at pattern recognition. Let's have a look at a pattern. It's dips

:57:37. > :57:41.like that that you want to find. That's it. Each point is a

:57:41. > :57:49.measurement of the star and a computer missed this one. But a

:57:49. > :57:56.human found it. And what do the viewers have to do? Go to the

:57:57. > :58:02.website. Six-year-olds can do this and just click. The more clicks you

:58:02. > :58:08.have an opportunity to find your own planet and you will be a God!

:58:09. > :58:14.We'll send you there, Dara. We need as many of you as possible to take

:58:14. > :58:20.part. You don't have to register if you don't want to and you can spend

:58:20. > :58:27.as little or as much time on there. Why wouldn't you want to spend a

:58:27. > :58:37.little bit of time to find your own planets. Go to the website and

:58:37. > :58:38.

:58:38. > :58:48.click on the box that says "find an exo-planet." Tomorrow night we're

:58:48. > :58:50.

:58:50. > :58:57.back with John Caulshaw. He's getting better and better at an

:58:57. > :59:01.impression of me. Now, get on to the website hunting for planets.

:59:01. > :59:07.This is real science we can really add to the sum total of human