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00:00Once upon a time, way back in the 1950s, the world was a very different place.
00:14In those days, world news was old news by the time it reached the telly.
00:20You had to pre-book a line to telephone America.
00:26And unpredictable weather meant thousands of lives were lost every year as ships ran aground and hurricanes arrived unexpectedly.
00:39And then something happened that would change the world beyond recognition.
00:46We entered the satellite age. And nothing has been the same since.
00:59This is the story of how we built satellites. And how satellites built the modern world.
01:161957. The United States was on the march.
01:35No one was in any doubt that America, the ultimate frontier nation, was about to lead us boldly into the space age.
01:52Space travel became headline news with the announcement that the United States planned to launch their first satellite by 1957.
01:58This was followed by reports of a similar project underway in Russia.
02:02The American confidence that they would be first in space was based upon the assumption, which seemed to be rock solid,
02:09that Americans are better than Soviets at anything to do with science or technology.
02:15And therefore, they almost didn't really even need to think about this possibility of the Soviets being first in space.
02:23But American scientists have been developing a man-made space marvel, the first Earth satellite.
02:29They've designed apparatus for coating it with a protective covering to withstand the extremes of temperature in outer space.
02:35The satellite is due to be launched sometime before the end of next year.
02:39And then, out of the blue, came the news that no one in the West had been expecting.
02:44On October the 4th, 1957, the Soviet Union launched the world's first satellite.
02:56Yes, signals from the Russian satellite, the red moon.
03:00The news of whose launching burst on the world like a bolt from the blue.
03:03The Soviet satellite is said to be about ten times as heavy as America's projected moon,
03:07and it circles the Earth every 95 minutes, over 500 miles up, at a speed of 18,000 miles an hour.
03:17The launch of Sputnik 1, I think, was a major event in world history, really.
03:21For the very first time, something had been launched out beyond the Earth's atmosphere,
03:26orbiting the Earth once every couple of hours or so, and it was the beginning of the space age.
03:31This had never been seen before. There was nothing in space. There was no satellite.
03:41So, at last, you have something as exciting as something in outer space.
03:50Possibly the most graphic reaction to Sputnik was in the United States,
03:54and that was a mixture of fascination, shock, or all the sorts of terms we know and love.
03:59But, globally, people were just amazed that, actually, the space age, long predicted, was now beginning.
04:10The world went Sputnik crazy.
04:18In Red Square, thousands celebrated Sputnik's launch and revelled in the Soviet propaganda victory.
04:24Khrushchev and China's Mao Zedong watched as the Soviet satellite triumph was demonstrated for all to see.
04:31For the thousands of spectators, this was the highlight of the whole show.
04:34The loons tell the story of the great scientific achievement.
04:45And then, it seemed that everybody was launching a Sputnik over the Red Square.
04:52As the Soviets rejoiced, people around the world turned on their radios just to hear Sputnik's bleeping broadcasts.
05:03And anyone with a telescope tried to catch a glimpse of the world's first satellite.
05:12Observations of bleep in flight have been made in many parts of the world.
05:18Pictures, too. Here, in a composite story, are the first films of the Red Moon.
05:23A fascinating glimpse of a man-made moon blazing the trail of outer space.
05:27I doubt when they would have seen Sputnik itself. It was only about this sort of size.
05:32But the rocket that actually put the Sputnik into orbit, the third stage, was about 17 feet long.
05:37And that would have been, I think, visible.
05:39The American establishment could listen to the Red Moon as it flew over US airspace.
05:51They even believed they could see it.
05:54But they could not track it.
05:56In desperation, they turned to Britain, who had just finished building a new bit of space-age hardware.
06:02In another scientific field, the giant radar telescope at Jodrell Bank in Cheshire was built as an aid to probing of outer space.
06:15In the event, it had scarcely been completed before its services were urgently required in charting the course of the Russian Earth satellites.
06:22Surprisingly, the Americans didn't have any large radio telescopes that could do this job.
06:26The Mark I telescope here was the only one in the world at that time.
06:31And so we were used by the Americans before they were able to build their own large space-tracking antennas.
06:36The Americans had barely learnt of Sputnik's whereabouts before they were dealt another body blow.
06:56Sputnik 2.
07:03And on board was a living, breathing and barking passenger.
07:10Her name was Laika.
07:14The first animal in orbit, Laika became an international superstar.
07:19But Muttnik, or Pupnik as she was known, had little time to enjoy her celebrity.
07:26Laika's ticket to space was one way.
07:38The Soviets had the atom bomb.
07:40And now they clearly had advanced, powerful rocket technology.
07:43After seeing the Soviets conquer space, many Americans began to fear that they might be next.
08:00The US space program went into overdrive.
08:05The date of America's first satellite launch was brought forward by 30 days.
08:16On the 6th of December 1957, the countdown began.
08:21America was finally going to enter the space age.
08:25The world's media gathered to watch.
08:27Is that a fuel leak there in the first section of the three-stage rocket?
08:35Disaster follows as this official film shows only too clearly.
08:44A big setback indeed, but probably more so in the realm of prestige and propaganda than in any other way.
08:50The Americans were terribly embarrassed, and the press called it oopsnik, flopnik, stay putnik.
09:03All playing, of course, on the Sputnik idea.
09:07But also drilling home this idea of American failure.
09:17Eventually, they got it right.
09:20In January 1958, at last, America entered the space age.
09:27But all that can be done to assure perfection has been done.
09:30The moment is at hand, the countdown reaches zero.
09:32Some three minutes later, Explorer is in orbit, broadcasting to the world its coded scientific data.
09:46The great era of the satellite was well and truly underway, and the driving force behind it was the military.
10:02Fantasists talked of lasers or missile launchers orbiting the Earth.
10:12But calmer minds realized that real potential lay in the realm of satellite surveillance.
10:17And surveillance, or spying, was a key weapon in the Cold War.
10:31Satellites played an important part in turning the Cold War from being a dangerous crisis, in which both sides were paranoid with fear about a surprise attack by the enemy, into a stable relationship.
10:45Before satellites, aerial surveillance was only possible in airplanes, but in May 1960, their vulnerability was dramatically exposed.
10:58An American U-2 spy plane, piloted by Gary Powers, was shot down over the Soviet Union.
11:11Three months later, the Americans launched Corona, the world's first spy satellite.
11:22Beyond the range of enemy missiles, Corona reassured the American military that it knew just what the Russians were up to.
11:33A year later, the Soviet Union countered with Zenit 1.
11:37A new era in Cold War espionage was born.
11:44That sense of paranoia, that sense of fear of what the other side was doing, that sense of the unknown, was suddenly removed.
11:52And you moved to a scenario where you knew everything that the other side was doing, or almost everything.
11:57Or almost everything.
12:04But spying was not the only area to benefit from satellite technology.
12:11Space promised the military much more.
12:13At the heart of the Cold War, the scenario involved firing hundreds of thousands of missiles over the North Pole.
12:27If you look at the surface of the globe, if you're firing an intercontinental ballistic missile,
12:31the shortest point between Moscow and Washington is over the top, not round the globe.
12:35The trouble with going over the North Pole is that the magnetic forces of the Pole can play havoc with a compass, sending missiles horribly off course.
12:47So, the American and the Russian military looked at trying to find a way to get round this.
12:58And using satellite-based navigation was one way to do it.
13:02In 1978, the Americans launched their solution, the Global Positioning System, or GPS.
13:15At the heart of the GPS system are 24 satellites, each constantly broadcasting the time and data about their location.
13:25Back on Earth, a GPS receiver can pick up these broadcasts.
13:29By calculating the distance between it and at least four satellites, the receiver can work out its precise location to within a meter.
13:42By putting a GPS receiver in a nuclear warhead, missiles could be guided accurately over the North Pole.
13:48Technology has miniaturized, and GPS receivers can now be mounted onto ever smaller weapons.
13:59Military commanders can now use GPS to guide battlefield missiles with pinpoint accuracy.
14:09But GPS has had other military applications, equally profound.
14:22GPS allowed army commanders to have an unprecedented degree of confidence in where they were on the battlefield.
14:29The best example of this in recent times has to be Operation Desert Storm in 1991, the famous invasion of Iraq by the US-led coalition.
14:45With GPS on their side, the coalition forces could attempt the previously impossible.
14:50400,000 American and allied troops advanced across the Iraqi desert at night and arrived unannounced at the back door of the Iraqi forces in Kuwait.
15:07The famous left hook led by General Norman Schwarzkopf.
15:10General Norman Schwarzkopf.
15:11Now this movement by so many troops, hundreds of thousands of vehicles and men, was all done because the lead tanks, the lead commanders of this force all had GPS devices in the turrets of their tanks.
15:25Satellites have given the West the ability to operate shock and awe tactics, destroying conventional armies and enemy governments with unprecedented speed and efficiency.
15:46GPS has been the biggest revolution in military affairs since the invention of the atom bomb in 1945.
15:52It's allowed what we now know today as the smart bomb scenario to be played out in so many wars.
16:01It's allowed military commanders to fight wars with a degree of precision, tempo and intensity that has not been seen before.
16:11Without GPS, the Western way of war as we know it today would not exist.
16:16Millions of us use a version of the military GPS system every day in our own civilian sat-nav kits.
16:27They get us from A to B easily.
16:34But no longer being late for dinner is not the end of it.
16:37Ambulances have cut their arrival times, no longer lost in unfamiliar back streets.
16:49The Coast Guard can locate sailors in distress by homing in on their GPS beacons.
16:54And on search and rescue missions, poor visibility and bad weather are no longer the obstacles they used to be.
17:09The civilian GPS industry is booming. Evidence of how the commercial value of satellites has been utilised.
17:15This desire to make money, to exploit the potential of space, has been behind some of the great satellite innovations of the last 50 years.
17:28In 1960, AT&T, the American telecoms giant, announced their intention to launch the first ever commercial satellite.
17:42Its job would be to relay television and telephone across the Atlantic.
17:47The satellite was Telstar.
17:50At Goonhillie in Cornwall, the post office built Arthur, a huge thousand-ton receiver whose job it was to pick up Telstar's first ever signal.
18:06But Arthur was not alone.
18:11The French also wanted to receive the historic transmission.
18:16They opted for a radical new design.
18:21The space-age equivalent of a giant ear trumpet.
18:31On July the 10th, 1962, Telstar took off.
18:36A television relay station in space.
18:39The British and the French sat down and waited for Telstar to appear over the horizon.
18:50Over half the nation tuned in to watch history be made.
18:56And it's four and a half minutes to go.
19:00The government even gave the BBC special dispensation to broadcast late into the night.
19:06At half past twelve, the live broadcast began.
19:11But whose receiver would pick up the signal best?
19:17Here we are.
19:19Here we are.
19:20There's a bar.
19:22Now, we are anticipating...
19:23That's a man's face.
19:25There it is.
19:27I remember staying up all night.
19:29I was in my sixth form to take photographs off the television screen of the very first pictures that actually arrived from America that night.
19:37So that was quite exciting.
19:39There's the unmistakable image.
19:41There is the first live television picture across the Atlantic with rather less than four minutes of available time left.
19:52While Britain had trouble adjusting Arthur, receiving only a few moments of poor quality reception, across the channel the minutely adjustable French ear trumpet was triumphant.
20:11Picking up 19 minutes of the broadcast.
20:20It was then that the French nearly sparked a diplomatic crisis.
20:25They made a surprise counter-broadcast back across the Atlantic via Telstar.
20:29Invading American screens was none other than legendary crooner Yves Montand.
20:38At that moment, a satellite star was born.
20:51Five weeks after the launch, British pop sensations the Tornadoes celebrated with Telstar.
20:58Now we take for granted the news reports broadcasting live transmissions from anywhere on earth.
21:15It's very easy to forget how remote everyone really was in the 1950s before the development of communication satellites.
21:25Events abroad no longer had to be filmed, packaged, put on board a plane and delivered to a broadcast centre.
21:31So, when a shocking event occurred across the Atlantic, Telstar united the world in grief.
21:38The BBC television news.
21:40At this moment, the national colours emerging from the rotunda.
21:50John F. Kennedy's funeral was broadcast live via Telstar around the world.
22:01Mourning became a global event, experienced simultaneously and collectively via satellite.
22:20Mourning was broadcast live via Telstar.
22:30Telstar sped around the Earth once every two and a half hours.
22:33It constantly came in and out of range of ground stations,
22:37providing only 20 minutes of transatlantic communication, once per orbit.
22:42So, Telstar was never intended to work alone in space.
22:45Telstar would have been one of a whole flotilla of dozens of medium-altitude communication satellites,
23:01providing telephone communication, TV broadcast around the world.
23:07Telstar cost AT&T 50 million dollars.
23:13Their plans to launch a further 40 were expensive and susceptible to technical glitches.
23:22The solution was to launch a satellite that would not move in and out of range.
23:29But to do that, scientists had not only to change the satellite's speed around the Earth,
23:34but also increase its altitude.
23:35In order to stay in orbit at a particular height above the Earth, you have to be travelling at the right speed.
23:49As you go further out, the speed has to change, and you go around the Earth more slowly.
23:54And it turns out that if you get out far enough, about 22,300 miles, then the speed at which you go means a spacecraft will stay above the same point in the Earth.
24:07The spacecraft will go around the Earth once per day, as underneath it the Earth rotates once per day,
24:13so the spacecraft stays in the same place.
24:15And this is basically what it's done with so-called geostationary satellites.
24:21This new breed of satellite no longer disappeared over the horizon, and there was an additional benefit.
24:27Typically, one could use three satellites to be able to send communications to any point on Earth,
24:34because of the visibility that geostationary altitude provides.
24:37But having solved one set of problems, engineers now faced another.
24:47Their new high-flying satellites had a habit of not staying still.
24:56A geostationary spacecraft, unfortunately, the orbit isn't actually stable.
25:00This is because the Sun and the Moon disturb the orbit,
25:03and it moves, it pulls the spacecraft off the ideal position, out of the ideal position in space.
25:10Now, to an observer on the ground, that would, the spacecraft then appears to move in a 24-hour period against the background.
25:18Now, in an extreme case, that can look like the spacecraft draws a figure of eight in the sky.
25:23Now, that would be a real problem for people, say, for direct broadcast television,
25:27people with antennas on the side of their houses.
25:29These are, to make them low-cost, they're rigidly mounted to the wall of your house.
25:34Now, if the spacecraft is moving over 24 hours, your antenna would have to follow the spacecraft so that you could keep your picture.
25:41So it's very important to keep the spacecraft in the same place in the sky.
25:45This is traditionally performed using chemical thrusters.
25:49These manoeuvres are referred to as station-keeping manoeuvres.
25:52So they are performing little adjustments on the spacecraft to keep the spacecraft in the same place, in the correct place in its orbit.
25:59What this new breed of geostationary satellites provided was unprecedented.
26:09A permanent, immediate and global communication network.
26:17The change was felt initially in sports broadcasting.
26:20The World Cup, for example, one of the great sporting events for many people around the world.
26:27That was nothing before satellite technology enabled live football matches to be transmitted around the world.
26:34When the World Cup came to Britain in 1966, the BBC prided themselves on satellite broadcasting that allowed the world to watch the finals.
26:52It was the biggest broadcasting event yet mounted in Britain.
26:57All 32 matches are reaching 42 countries in the world.
27:02Their audience on Cup Final Day is expected to be 400 million people.
27:10Soon broadcasters were arranging lavish live spectaculars, allowing people to tune in and marvel at the idea of watching other parts of the world live in real time.
27:21Viewers were riveted by a mariachi band in Mexico City, a baseball game in Houston, and a game of cricket from Kidderminster.
27:36What a stroke.
27:38Satellite television made the world seem smaller.
27:42In the end, when there are more satellites still, you'll have television and telephones all over the globe, a shattering thought.
27:48The growing global demand for better coverage, and for more and more channels, saw hundreds of satellites put into orbit in an attempt to satisfy the needs of viewers.
28:04Critical to this revolution in communication was the ability to direct satellite beams with great precision.
28:23To get this right, engineers had to test them in a room like this.
28:27This is the planar antenna range, used primarily for the measurement of large radar antennas, and communications antennas for both science and telecommunications.
28:39If we haven't set up the antennas correctly on the satellite, the signals which are coming to the satellite or from the satellite may well not be in the right place.
28:54If you're putting them down onto the Earth, the important thing you have to remember is that at 25,000 miles up, where our geostationary communication satellites are, 7.7 degrees covers the whole of the Earth.
29:06So if you're out by a fraction of a degree, the signals that should sit over, say, London, could well be sitting over Dublin.
29:13Now, if the Irish government want your signals, that's very nice, but if the English government want your signals, that's not very good.
29:18By mounting a satellite antenna opposite a moving receiver, Brendan is able to measure precisely the alignment of the antenna's beam.
29:32The blue foam spikes absorb off-target beams, stopping them ricocheting off the walls, bouncing around the room and confusing the readings.
29:42In a planar range, the antenna which is under test is perfectly stationary, which means we can have very big antennas up there which we can't move about because if we move them, they may damage themselves in one way or another.
29:55And the probe, which is doing the measurements, is actually going to move up and down and we then capture this information and then look and see how well this antenna is working.
30:06Today, we no longer need ground stations the size of Goonhilly to receive or transmit pictures.
30:22Mobile broadcasting equipment means television can come live and direct from anywhere on Earth, so long as you can see the sky.
30:30Well, there's no such thing as a normal day, really, in this line of work. In the past, I've gone into work at 9 o'clock in the morning and by 5 that evening I've been in a different country.
30:45Using a bit of prior knowledge about the satellite that we're trying to access, such as its position in the sky and its beacon frequency, I can align our dish to the satellite.
30:55The thing is, the satellites are geostationary, so they're always in the same position in the sky.
31:00So, if you turn up at a location, the simplest way to find the direction of the satellite is using a standard compass that you buy in a camping shop.
31:09Our satellite that we're using today is at 12 and a half degrees west of south.
31:14So, I turn up at a location, jump out of the van with my compass and point it at 12 and a half degrees west.
31:19And if there's a skyscraper in the way or a huge tree or any other kind of obstruction, I know that I have to move the van elsewhere so I can achieve a clear line of sight to the sky.
31:33So, the thing we do now is, we just tweak the dish and align it so we get maximum signal strength out of it.
31:41And what you want to do is get this spike as high as possible, which will give you the best signal transfer.
31:47Hello, SatOps, it's UPI 888 here, booked on K Kilo.
31:53Broadcasting by satellite used to be a newsworthy event in itself. Today, it's a standard part of the news chain.
32:05Live broadcasts from the most remote, most hazardous locations have changed our news, and through that, our view of the world.
32:13I think this sort of technology has really changed people's perception of news, because it's improved the immediacy of it.
32:23Whereas in the past, it took days to get pictures back from some far remote war zone, disaster zone, whatever.
32:30Now you can do it really within a matter of hours. As soon as your satellite terminal is on the ground and transmitting, that's it. You're on the air.
32:37Nowadays, satellites are constantly passing overhead. On a clear night, anyone can see them. In fact, a whole new hobby has been born.
32:53Phil, we've got a pass of one of the American spy satellites in just a couple of minutes now.
33:12Meet Phil and Mike, two of the world's leading amateur satellite spotters.
33:17We expect this satellite to come up in 50 seconds. It's coming up in the southwest.
33:25The satellite's 2,000 kilometers away, but closing about 8 kilometers a second.
33:32Three, two, one.
33:38Yep, got it in the main camera.
33:40We're going to zoom in.
33:41We just need a bit of adjustment on the focus there.
33:47This is a spy satellite called LaCrosse 5.
34:00And we can just about begin to see a little bit of structure.
34:05We can usually resolve the large solar panel or radar panel on this satellite.
34:10We observe this quite a bit because it's one of the few satellites that we can actually resolve some shape on.
34:17So it's one of our favorites.
34:19The orbit of these satellites is not actually published by the governments that own them.
34:24But there are a number of amateurs around the world who make observations as they go through the sky.
34:29And with enough patience and computing, you can then work out the orbit from those observations.
34:37But we're not actually giving away any military secrets here.
34:42But the LaCrosse satellite is not the only one that's been keeping them busy.
34:47We've been concentrating on the space station, which has had a continual construction program since about 1998, in fact.
34:57And over the last six years, they've been gradually adding to it, taking up various parts of the structure in the space shuttle cargo bay.
35:04And adding the various panels and crew habitation modules to it, gradually building it up.
35:08It's really great to be able to see the space station in that detail and to know that not many people around the world are able to get these types of images using amateur equipment that we've got.
35:19And to know that the software and so on was written by us as well.
35:25Recent footage shot by Mike and Phil shows the shuttle docked with the International Space Station.
35:31No other amateurs in the world have been able to create such stunning images.
35:41We're quite unique in the world in being amateurs and producing this quality of footage.
35:47There are some semi-professional people around the world who achieve this.
35:51But we're leading the field for the amateur fraternity.
35:54As we look up at them, satellites peer down at us.
36:08Their view of the world has changed the way we picture our planet and has transformed the way we understand its weather.
36:14In the 1950s, meteorology was more art than science.
36:25Forecasting was stuck in the past, occasionally with tragic results.
36:33In 1954, the Toya Maru, a Japanese ocean liner, sailed directly into a typhoon that forecasters thought had dispersed.
36:42Over 1,200 lives were lost.
36:46It was one of the worst maritime disasters of the century.
36:51As international trade and travel boomed, the modern world demanded better forecasts.
36:58Satellites offered just that.
37:00The first dedicated weather satellite was Tyros-1, launched in 1962.
37:18Its photos were assembled into mosaics, which provided a whole new way of picturing the world's weather systems.
37:24But despite the early promise, forecasters faced a problem.
37:30The problem was, you could only get that image when the satellite was passing overhead, which turned out to be about twice a day at maximum.
37:38So they weren't available all the time.
37:42And then you had to disseminate it.
37:45And quite honestly, in the early 60s and 70s, we didn't really have the ability to disseminate it to the people that mattered.
37:51And the people that really needed these pictures were the forecasters themselves, so they could analyse the atmosphere and make predictions.
37:59In the days before the internet, images had to be sent via fax, which further reduced the quality of the pictures.
38:06When the meteorologists, even at the universities, looked at pictures like we have here from Tyros, we can see swirls of clouds.
38:16You can see the overall view that there's a depression there.
38:19But what you can't see is the detail.
38:20You can't see the detailed cloud structures, where there's frontal systems, for example, where there's heavy convection as opposed to light convection.
38:28So, tremendously exciting because it's the first time that forecasters or meteorologists have seen a view from space.
38:33But in terms of the detail required to get very detailed weather forecasting, it's not quite there.
38:42As technology improved, it was clear that satellites had the potential to revolutionise weather forecasting.
38:49But first, meteorologists had to develop the skills to understand the pictures.
38:57Now this was a whole new ball game. They had these images.
39:00They had to develop conceptual models so these images meant something to them in terms of what the atmosphere was doing, meant something about the dynamics of the atmosphere.
39:10They had developed that using conceptual models looking at frontal chart pictures.
39:15Now they had to do the same thing using satellites.
39:18Developing these conceptual models took time.
39:28In October 1987, they were put to a stern test.
39:33On Thursday the 15th, the satellite showed something big brewing in the Bay of Biscay.
39:39The problem the forecasters faced on the Thursday afternoon was the models were giving conflicting signals.
39:47Some had been going for a great storm or some had been going for a very good gale from as early as Sunday.
39:53And some were going for nothing happening at all with just a sort of gale up the channel.
39:58Michael Fish presented what would become an infamous forecast.
40:08Earlier on today, apparently, a woman rang the BBC and said she heard that there was a hurricane on the way.
40:13Well, if you're watching, don't worry, there isn't.
40:15But having said that, actually, the weather will become very windy.
40:18But most of the strong winds, incidentally, will be down over Spain and across into France.
40:22It was one of the worst storms Britain had ever endured.
40:39I think with hindsight, I think we can see that a fairly intense feature is developing in Biscay.
40:45But in these days, satellites were still only just one tool.
40:48They weren't as important as they are today.
40:50Nowadays, forecasters would be much more alert to this being a severe storm than they were back in 87.
40:59Modern satellites have made weather forecasts more accurate than ever.
41:03They've allowed us to see, in incredible detail, weather patterns around the world.
41:08And even to study patterns invisible to the naked eye.
41:19It will prompt thunderstorms.
41:20And through Northern England and Northern Ireland, persistent rain.
41:23You're used to that sort of forecast and what you see here, you're familiar with.
41:28The blue is a forecast of rain and the brown, the amount of cloud expected to go with it.
41:33All from a pretty accurate Met Office model, which covers the entire world now and is pretty reliable,
41:39largely helped now by the excellent resolution, accuracy and reliability of satellite-derived data, satellite imagery.
41:46Again, you're fairly familiar with that, I dare say.
41:50This, for example, is a picture you would see if you were sitting on the satellite and looking down.
41:55That is what the eye picks up, the top of the clouds, if you like.
41:58And the brighter it is, so the more ice it contains.
42:02Lovely picture, but only of any use when the sun is up.
42:05Which in the height of summer could be 16 hours a day.
42:07But in a gloomy winter, it could be 2 hours a day if you're lucky.
42:11So clearly it's a very limited use, from my point of view as a forecaster, from your point of view, to see what's going on.
42:17So we need to shift the channel, shift the frequency the satellite looks at, which is pretty easy to do, of course.
42:23It's only electronics.
42:25And then you have an infrared picture.
42:27Now this can be used even if there's no sunup, because it's detecting the temperature, if you like, of the cloud,
42:32which is shown by different shades of white.
42:34The brighter the white, the lower the temperature.
42:35So I can get an idea of either how high in the sky a layer of cloud is, or how deep the entire layer is.
42:42Which is quite useful, from a forecasting point of view.
42:45And pretty picturesque as well, you can get the swirls.
42:48And obviously there's nothing round the edges.
42:51Or is there?
42:53Just tune to a different channel and you catch water vapour.
42:57Of course the atmosphere is full of water vapour.
42:59And watching where that goes is quite useful for me.
43:02You're never going to see this on television.
43:03You know, it's just a grey mess.
43:04There's nothing very exciting going on.
43:06But you might see different shades of grey.
43:08And that's what interests me.
43:10Where that grey gets darker and darker, or even goes black,
43:14well the air is dry.
43:15Now why would the air be dry?
43:17Usually because it's being drawn down from above from the stratosphere by a rapidly developing depression.
43:22Big area of low pressure. A big storm.
43:23Which will produce rain and extremely strong winds.
43:31Satellites can't stop the weather.
43:33But they can allow us to prepare for the worst.
43:38In the summer of 2007, as rainfall approached record levels,
43:41satellite data prompted the Met Office to issue severe weather warnings.
43:50So when the devastating floods arrived, the emergency services were ready to swing into action.
43:56Weather forecasting is not just about taking your mark on whether you want to play golf.
44:04Weather forecasting is about saving lives.
44:06Not just in the United Kingdom, but globally.
44:09It's very important to track hurricanes, tornadoes, thunderstorms,
44:12any form of severe weather that could be a hindrance to transport systems,
44:17cause chaos on the roads, cause loss of life.
44:20Weather forecasting is an extremely serious business.
44:22Satellite imagery allows us to see our world from a fresh perspective.
44:43These are irrigation circles in Saudi Arabia.
44:52This is the Thames, flowing out of London.
45:06Here are the canals of Venice.
45:10To do this, camera technology has had to evolve.
45:14Today, modern space cameras barely resemble their counterparts on Earth.
45:19One of the unique things about this camera is there are actually no lenses.
45:25This camera consists of just three mirrors.
45:27And three mirrors is really the minimum number of mirrors that you need in order to achieve an acceptable image.
45:33The camera works by light entering from the front of the camera here.
45:38It then comes in onto the primary mirror, which you can see is the outer annulus of this large mirror here.
45:45It's then reflected back onto a secondary mirror.
45:49It then gets reflected a second time onto the third mirror, the tertiary mirror here,
45:55which is then brought to a focus where we place the detector.
45:59And it's the detector that then turns this light from photons into electrons that can then be read by the computer.
46:06The detector is very similar to the detectors that you have in your cameras at home.
46:09It takes an image and then stores it down to a memory card.
46:13And then in the case of this camera, that's then downloaded back to Earth.
46:18And these mirrors are actually flight quality mirrors.
46:21They're very, very expensive mirrors.
46:23They actually cost the same as an Aston Martin.
46:25They cost about £200,000.
46:27And the reason for that is because they are extremely high quality.
46:30They have to be in order to achieve the image quality that we need.
46:33The internet is just a little bit different.
46:35And again, it's like a high quality perfect,
46:36and that's our time to see if they are on board.
46:37And the lights are bright, and we don't have to be in order to be in order to be in order to be in order.
46:38So let's see if they are in order to be in order to be in order to be in order to be in order to be in order to be in order to be in order.
46:41Satellites haven't just changed our view of the Earth and its weather.
47:06They've changed the way we understand the entire universe.
47:11Four, three, two, one, and liftoff of the space shuttle Discovery with the Hubble Space Telescope, our window on the universe.
47:23The most famous of all space telescopes is Hubble.
47:29Costing one and a half billion dollars, Hubble was one of NASA's greatest undertakings.
47:36Its mission was to help scientists unlock the secrets of the universe.
47:42But Hubble was very nearly a disaster.
47:46When Hubble finally sent back its first images, it was actually a very, very big disappointment.
47:52The images were good, and they were in many ways better than what you get with a ground-based telescope.
47:56But they were nowhere near as good as people were expecting.
47:58And what had happened was that the images just weren't sharp enough.
48:01They just seemed a bit blurry and a bit out of focus.
48:04The conclusion we've come to from that is that there's a significant spherical aberration that appears to be present in the optics, in the optical telescope system optics.
48:17Hubble's problems stemmed from its primary mirror, and this had been incredibly precisely ground, but to ever so slightly the wrong specification.
48:26And eventually, working back, the team worked out that the edge of the mirror was just slightly too flat.
48:33And only about two micrometers too flat, that's less than a 20 at the thickness of a human hair.
48:38So it's a very, very tiny, a tiny error.
48:45With their pride at stake, NASA launched a daring rescue mission.
48:50In 1993, Space Shuttle Endeavour rendezvoused with Hubble.
48:57Orbiting the Earth at 16,000 miles per hour, the astronauts installed CoStar, an optic system designed to compensate for the floor in the mirror.
49:09And I'm happy to announce today, the trouble with Hubble is over.
49:15I think you got it.
49:16When the correct images came down, it was a huge relief.
49:21And they were spectacular, and they were as the telescope had originally been envisaged.
49:25And the difference between before and after, it's like it's a different telescope looking at the images.
49:29They're much, much clearer.
49:32Hubble showed us wonders like the Eagle Nebula, 7,000 light-years away.
49:39There, in columns of dust and gas trillions of miles high, stars are born.
49:46Hubble has even helped astronomers estimate the age of the Universe to be 15 billion years old.
49:55And it confirmed that the Universe is still expanding rapidly.
50:01But Hubble is just one of many space telescopes.
50:07Today, there are over 3,000 satellites in orbit, and more are being launched every month.
50:19They're tracked here at Filingdales, the RAF's Space Surveillance Centre, and for good reason.
50:26With every rocket launch, hundreds of bits of debris are jettisoned into orbit.
50:35In the vastness of space, collisions may seem unlikely, but they have happened.
50:41When Cerise, a spy satellite, unexpectedly went offline, Filingdales had a bit of detective work to do.
50:52Satellites often go wrong, but usually it's caused by batteries going flat, circuit boards blowing.
51:00Cerise turned out to be a bit more of an unusual event than that.
51:04We knew what it looked like. It was basically a small box of electronics with a boom sticking out of the top,
51:14called a gravity gradient boom, which kept it nice and steady on orbit.
51:18When we came to track it, after we got the phone call, we found that it wasn't stable in orbit.
51:24It was tumbling end over end.
51:26By analysing the orbits of thousands of satellites and space junk, Filingdales unearthed a clue,
51:36a piece of debris from a French rocket.
51:40It had been stably orbiting the Earth for ten years, but mysteriously, it was no longer where it should have been.
51:47Its orbit had shifted.
51:49We found that the time it changed orbit was exactly the time it had been close proximity with the Cerise payload.
52:02Which rather led us to the belief that there'd been a collision at that time.
52:12Collisions are rare, but just one major impact could create a million pieces of junk.
52:19Putting our entire fleet of satellites at risk.
52:24One can imagine that collisions between spacecraft, the creation of space debris,
52:29can itself trigger almost an exponential effect where that debris causes other collisions and so it goes on.
52:38And we can end up with clouds of debris that effectively could preclude the utilisation of those areas of space for any application.
52:46For most of us, satellites are out of sight and out of mind, and a collision in space seems a remote threat to our way of life.
52:59But in fact, it's just one of a growing number of dangers which could put everything satellites have brought us at risk.
53:06If you look at communication satellites, for example, then it is relatively easy, both accidentally but also deliberately, to jam the signals out of these satellites.
53:21Typically, it's not deliberate, it's something that's accidental and that can be sorted.
53:25But in other cases, more rare cases, but very importantly, it can be deliberate.
53:32China, a well-ordered and highly regulated society.
53:38China, a well-ordered and highly regulated society.
53:41Where the government keeps a close eye on what people do, read and watch on TV.
53:49in 2002 the state broadcast the World Cup via satellite hundreds of millions
54:01were allowed to tune in but suddenly the channel broadcasting the football came
54:10under attack someone was hacking into the signal the government accused the
54:16Falun Gong an outlawed religious organization instead of the football
54:23millions of viewers found themselves watching outlawed exercise routines the
54:31government could do nothing to stop it the satellite was jammed for eight days as
54:43the global network of communication has been built so an underground network of
54:48hackers and jammers is emerging
54:54any well-organized terrorist group could now hijack our communication satellites
54:59and appear without warning on our screens
55:04hacking is no longer the only way to attack a satellite
55:08China is facing international criticism after it used a ballistic missile to destroy a satellite in
55:23space that news sent shockwaves around the globe an entirely new way of fighting wars had emerged and our satellites were now on the front line
55:37the 2007 Chinese anti-satellite weapon test is perhaps a major turning point in the 21st century for the first time a weapon has been used in space to destroy a satellite
55:56the attack was ingenious and perfectly executed what was most frightening was that it didn't require any new technology
56:07to understand this test you have to get out of your mind concepts of missiles lasers and all that sort of science fiction type portrayal of war in space
56:19the phrase kill vehicle has been coined to describe the Chinese weapon test this involved another satellite another space vehicle being maneuvered in space onto a similar orbit and then directed to collide with the target vehicle
56:44the physical collision caused enough damage to put the target vehicle out of action
56:53a first strike attack on our satellites could blind the western military and cripple resources crucial to modern society
57:04merely launching satellites is no longer enough
57:12our futures now depend on protecting those already up there
57:16space could become a battleground for a whole new type of warfare
57:2250 years on from the launch of the world's first satellite sputnik we have an event of similar significance
57:30we now have a situation where the world's reliance on satellites to provide communications reconnaissance and many other things that we take for granted today are under threat
57:41orbiting the world at a height of 500 miles sputnik ushered in the space age
57:49the satellites that followed spawned a new era here on earth and helped build the modern world
57:57initially the preserve of the military satellites went on to herald the information age
58:05a time of broadcasts and instant communication
58:10and they gave us security to the weather is easier to predict and forecasts save thousands from storms
58:17we can safely navigate our way across deserts or unfamiliar seas
58:24satellites once safe in the sanctuary of space
58:32are now the vulnerable outposts of our modern society
58:36after 50 years of progress their future is now uncertain
58:41next tonight marcus brigstock is back with another late edition
58:53we'll see you
59:06Amen.
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