Journey Through The Solar System, Episode 09 - Jupiter Odyssey
Transcript
00:00Jupiter is the fifth planet from the Sun.
00:20The mass of Jupiter is twice that of all other planets in the solar system combined.
00:29I'm Larry Ross, Director of Space Programs at NASA's Lewis Research Center in Cleveland,
00:33Ohio.
00:34And I'm your host for this ninth program of the 13-part series called Journey Through
00:39the Solar System.
00:59During this program, you'll see the NASA film titled Jupiter Odyssey.
01:26It's about the Pioneer 10 spacecraft launched by the Lewis-managed Atlas-Centauri.
01:32The probe had the nearest approach to the planet on December 3, 1973.
01:38Today, we have a clearer picture of Jupiter and its moons than is presented in the upcoming
01:43film.
01:44The reason?
01:45The more advanced Voyager spacecraft later flew by the planet.
01:50We will look at the Voyager project in another program and learn newer details, such as the
01:55current count of 14 moons.
01:58This program's older film reports that there are 12 moons.
02:03Now let's see that movie, which shows our first good look at Jupiter in 1973.
02:18They used to be called heavenly bodies.
02:21Our local star, prime mover of the earthly environment, father of all life.
02:28Our almost twin satellite, phasing predictably through the night.
02:34Small wonder both were regarded as gods by the ancients.
02:38Today we know the moon as a place.
02:42Now picture, if you will, a fantastic world where not one, but 12 moons crisscross the
02:48sky, four of them moving backwards, four others the size of small planets.
02:55This is Jupiter, largest member by far of the sun's family, monarch of the outer planets,
03:02a thousand times the size of Earth.
03:05In fact, twice as large as all the other planets combined.
03:09It is nearly a small star, a second sun, Jupiter, named for the Roman god of gods.
03:17To our eyes, it reveals only its dazzling cloud tops, rivers of wild color, and its
03:23trademark, the great red spot, a perpetual storm of unknown origin.
03:29On Jupiter, day and night are each less than five Earth hours long, and a man would weigh
03:35500 pounds.
03:39In early 1972, mankind launched Pioneer 10, the first mission to the outer planets, the
03:45first to venture out beyond the orbit of Mars, out through the Jupiter system, and
03:51eventually out of our solar system completely.
04:02The planets of our solar system come in two varieties.
04:05The inner four, including Earth, are heavy, rocky cinders.
04:09Where the fifth should be, there's only a band of debris, the asteroid belt.
04:16Beyond ride the enormous outer four, the mysterious gas giants.
04:23Astronomers have studied them since the time of Galileo.
04:26It was he who discovered Jupiter's four large moons with his newly perfected telescope.
04:33Beautiful ring Saturn, third of the gas giants, Uranus, rotating on its side, it circles the
04:39sun like a fallen gyroscope.
04:43And finally, Neptune, one of Neptune's moons, and one moon belonging to Uranus, were discovered
04:50by this modern Galileo, the late Dr. Gerard Kuiper of the University of Arizona.
04:59His backyard in Tucson has flowers, a swimming pool, and a private observatory.
05:10Here at Catalina Peak, his studies have produced some of the most outstanding color photographs
05:15ever made of Jupiter from the Earth's surface.
05:21This is sort of a typical photograph which shows the red spot of the planets, which is
05:27the most prominent feature.
05:29This black spot here is the satellite shadow, is the satellite EO, which is the nearest
05:34of the four large satellites of the planet.
05:37The satellite itself is here and doesn't show very well contrasted to the planet itself.
05:45Now the first thing you see is first, of course, that the disk of the planet is elliptical.
05:50That is because of its rapid rotation, which is roughly 10 hours.
05:53The period is roughly 10 hours.
05:55The diameter of this planet is about 10 times the diameter of the Earth, so this is a gigantic
06:00planet.
06:01The total mass is not, however, a thousand times.
06:04The volume is a thousand times, but the mass is only about 300 times that of the Earth.
06:09So the mean density of this planet is somewhat like the Sun, and that is because it is largely
06:14composed of hydrogen.
06:15So the composition of this planet is very, very different from the Earth, and very similar
06:21in fact to the Sun, except the temperature, of course, is much lower than the Sun.
06:26And because the temperature is low, you get a chemistry here which is totally different
06:29from the Sun.
06:30So you have all these interesting colors here, and what we have been doing in recent years
06:36is to try to understand both the motions of all these clouds and their composition.
06:47Our odyssey to the outer planets begins here at Cape Kennedy.
06:52A good omen, under a mock Jupiter sunrise, the ungainly, pregnant guppy delivers a special
06:58cargo.
07:10The Jupiter Pioneers were built by TRW Systems of Redondo Beach, California, under contract
07:15to NASA�s Ames Research Center.
07:18The project involves some 25 million man-hours of meticulous work by the government-industry-university
07:25Pioneer team.
07:26Each marvelously compact and reliable spacecraft weighs less than 600 pounds, including some
07:3265 pounds of scientific instruments.
07:36The 11 onboard sensors include five radiation and charged particle detectors, one magnetometer,
07:43and three light-measuring devices, one for the visible spectrum and one for either end
07:48of the visible range, the infrared and the ultraviolet.
07:53There's also an experiment to look for asteroids, and one to measure the number of times Pioneer
07:58is struck by space dust.
08:01All of these devices together use less electricity than one 25-watt bulb.
08:07That's energy conservation.
08:10Two other investigations dig out new information about the Jupiter system from ground tracking
08:15data.
08:18The question arises, what can 65 pounds of space-borne instruments tell us that Earth's
08:24finest facilities can't?
08:27For example, the famous Mount Palomar telescope with its 17-foot diameter glass eye.
08:42A scientist who uses both Pioneer and Palomar is Dr. Guido Munch of Caltech.
08:49We have used the 200-inch telescope extensively for planetary observations.
08:56This is the largest operating telescope that has ever been built.
09:01With this telescope, the planet Jupiter appears of the size of a 50-cent piece.
09:09The Pioneer infrared experiment will provide a map of the heat emitted by the planet with
09:20the 3-inch telescope, but at the distance of closest approach, the planet will cover
09:27one-fifth of the sky.
09:30And this is the advantage that we get from the 3-inch telescope to the ground-based really
09:38large telescope here.
09:40The need to measure the quantity of heat accurately is that all the meteorology, all the motion
09:48of the clouds that we see in Jupiter is governed by the amount of heat coming from the inside.
09:54And we hope that a real understanding of the meteorology of Jupiter will in fact provide
10:01us with a better way to handle our weather problems.
10:12The second day of March 1972, Pioneer 10 waits for launch atop a new three-stage version
10:19of the Atlas-Centaur rocket.
10:30Thirteen months later, a sister spacecraft, Pioneer 11, left the pad on its long and chancy
10:48voyage to Jupiter and Saturn.
10:57It's not easy to break out of the solar system.
10:59It requires enough speed to defeat the sun's gravity as well as Earth's gravity.
11:05Pioneer streaks away faster than any previous spacecraft, gulping distance at a million
11:10miles a day, passing the moon in just 11 hours.
11:16Still, Jupiter is nearly two years away.
11:22On the way out past Mars, the experiments are tested and calibrated.
11:26Their data add to mankind's understanding of the interplanetary climate of space.
11:37The asteroid belt, as some had imagined it.
11:40Before Pioneer 10, it was pictured as a region where great boulders grind together, creating
11:46a 40,000-mile-per-hour sandstorm.
11:49If so, it might have represented a perpetual barrier to outer planet flights.
11:56In fact, the Pioneers found very little space dust in the asteroid belt.
12:01True, there are several thousand asteroids, some as big as Texas, but they should offer
12:05no menace to navigation.
12:10Pioneer gets its electricity from small onboard atomic heat sources.
12:14At a half-billion miles, the sun is too weak to power solar cells.
12:19The spacecraft spins five times a minute for stabilization.
12:22On ground command, small thrusters fire to maintain the spin rate and to keep the large
12:27dish antenna precisely pointed at the receding Earth.
12:31This radio link is a two-way street.
12:33A constant stream of information flows back about the health of the Pioneer and its scientific
12:38observations.
12:43Pioneer is managed and controlled from Ames Research Center located at Mountain View,
12:48California, near San Francisco.
12:51The nerve center is in this building.
12:56Pioneer Project Manager Charles F. Hall.
12:59We're in the mission control area for Pioneer 10, and behind us is the mission control room.
13:08Right now they're preparing to send a few commands up to the spacecraft merely to change
13:14the attitude of one of the instruments, the operating mode, so that we can look on Jupiter.
13:20The interesting feature here is that the round-trip light time, the time to get a message
13:25from here up to the spacecraft, and then to get a return answer is an hour and a half.
13:31So our people in there have to be used to this hour and a half delay when they start
13:37planning the mission.
13:38Command to Arkan.
13:39To Arkan.
13:40We just received a stack clear message.
13:41Roger.
13:42Arkan Command will verify command stack loaded, block message number 9, first command IP Whiskey
13:522, time 141032.8.
13:53Roger.
13:54Copy.
13:55We're enabling message 10 at this time.
14:01The Pioneers are run by men who send commands from Earth, not by automatic systems on board.
14:08This cuts complexity and costs.
14:11During encounter, it's busy here.
14:13For example, to command just the electronic camera that makes pictures of Jupiter, Pioneer
14:19control transmits some 15,000 commands in just two months.
14:25In response to these commands, the camera scans Jupiter's turbulent cloud tops as Pioneer
14:30spins toward encounter.
14:33Because the spacecraft is moving at up to 80,000 miles per hour, and because Jupiter
14:38is rotating at 22,000 miles per hour, the scans do not immediately form a pretty picture.
14:44They must be decoded and corrected for distortion.
14:51First, the scans are built up line by line on a television display.
15:00This gives a quick look at the operation of the system and a tantalizing hint to the spectacular
15:05pictures buried in the raw data.
15:09After the first stage of prettying up, Jupiter's first close-up portrait emerges.
15:18Late November 1973, 20 months after launch, Pioneer 10 closes in on Jupiter.
15:25Each hour brings the planet 20,000 miles closer.
15:30What lies below those inscrutable cloud tops?
15:34Could there be life in this maelstrom where pressures may reach 200,000 times Earth's?
15:40There are scientists who think that the answer might be yes, that deep in this raging atmosphere
15:46of ammonia, marsh gas, and helium, the self-replicating spark may have been struck.
15:54One believer is Dr. Carl Sagan of Cornell University.
15:59Jupiter has an atmosphere rich in hydrogen and its compounds, the same kind of atmosphere
16:04that the Earth had at the time of the origin of life.
16:07So we think that the building blocks of life, at least earthly life, are being produced
16:12on Jupiter today, raining down from the skies like manna from heaven.
16:18And Jupiter may be a vast planetary laboratory in the chemistry of the origin of life that's
16:22been working for about 5 billion years.
16:25It's by no means out of the question that there are forms of life in the clouds of Jupiter.
16:30And indeed, if you viewed the solar system from afar, I think you could make an argument
16:35that life on Jupiter was more likely than life anywhere else, including on the Earth.
16:39Dr. Sagan also provided for Pioneer the famous picture postcard to extraterrestrial life.
16:45But in the remote contingency that there are interstellar spacefaring societies which might
16:51someday pick up this derelict no longer radioing, we thought we would put a message on it to
16:58indicate a little bit of where we are, when we are, and who we are.
17:05We think that the information on where we are and when we are, indicated in this part
17:09of the message by the configuration of certain cosmic objects called pulsars, will be completely
17:15obvious to any society capable of traveling between the stars.
17:20These two objects will be more mysterious because it is unlikely that there will be
17:24human beings anywhere else, even though there may be other creatures elsewhere.
17:28And the practice served a very useful purpose in making us think about what sort of impression
17:34we might wish to give to the cosmos.
17:39Each morning, the key scientific investigators and the key spacecraft personnel meet in the
17:44office of Pioneer project manager Charlie Hall for a stand-up meeting.
17:50Why not a sit-down meeting?
17:52Because, says Charlie, people don't talk so long when their feet get tired.
17:56The lack of contrast, I guess, is a bit of a worry.
17:58I have the impression that it is all in the picture.
18:00I don't know for sure that it is all in the picture.
18:03With such accuracy, but just grossly, whether we can trust the angles on the SEDS.
18:06I'm afraid to say anything because I don't know.
18:08We'll have to get to it.
18:09Say 250 degrees or something like that, system three, which is not far from what the radio
18:14astronomers have inferred.
18:15We have three sets of accurate observations with the IPP this week since the last precession
18:22maneuver.
18:24What we're seeing here is that for both electrons and protons, we're seeing, in first approximation,
18:33an in-phase change.
18:34But don't you know, you're not at that, no, it's all right, you're doing it pretty consistently.
18:40December 2nd, 1973.
18:43Tomorrow, Pioneer will make its closest pass of Jupiter when this fantastic world will
18:48fill one-fifth of the sky.
18:51Today, Pioneer is being cooked by incredibly severe radiation, yet everything continues
18:57to work perfectly.
19:00This spectacular picture shows the shadow of the satellite Io, just as Dr. Kuiper's
19:05ground-based photo did.
19:07From this distance, new details in the cloud bands become evident, huge coiling storm areas
19:13larger than the Earth.
19:16Since launch, Pioneer has been slowing down.
19:19Now the pull of Jupiter's gravity speeds it up to a fantastic 82,000 miles per hour.
19:27In effect, this crack-the-whip left turn gives Pioneer another rocket stage to fling it out
19:33of the solar system.
19:35Unexpectedly, the space dust count soars a hundred times as many hits.
19:41Jupiter's gravity may act as a cosmic vacuum cleaner.
19:49December 3rd, Pioneer sweeps to within 81,000 miles of the cloud tops.
19:55Now things happen fast.
19:57Fifteen minutes after closest approach, the spacecraft is targeted to pass out of Earth's
20:02sight behind the orange moon Io for a critical two minutes.
20:07This ultra-precise maneuver will use radio effects to reveal new information about Io
20:13if the signal can be picked up again on the other side, and if Pioneer will obey commands
20:19again.
20:21Back at mission control, there's a maternity hospital atmosphere.
20:25They won't know what happened in space until 45 minutes later.
20:29The speed of light is much too slow for the anxious parents.
20:59We missed the Io occupation by one second, and I was just sort of kidding him or telling
21:17him that you have to go through the ecliptic at the right time when the Io goes in front
21:24of you.
21:25We're three Jupiter radii away, Io's six Jupiter radii.
21:28You've got to get all this thing lined up, and we missed it by a second.
21:33Next time we'll do better.
21:34An hour later, Pioneer passes out of sight of both Earth and Sun, this time behind Jupiter.
21:42The spacecraft is collecting its worst radiation exposure now.
21:46Tension is even greater this time, and so is the relief.
21:53Now Pioneer views a sight never before seen by man, the crescent Jupiter.
21:58From Earth, we can see only its full phase, like a full moon.
22:02These lighting angles give scientists new information.
22:07On the television system, the images rapidly become smaller.
22:10Now several consecutive pictures can be stored on the tube at once.
22:15Thanks to energy literally stolen from Jupiter, Pioneer 10 departs more than twice as fast
22:21as it arrived.
22:26Now the world wants to know, what have we learned?
22:32The scientists readily admit to newsmen that for each question answered, a hundred new
22:37ones have been raised.
22:41Project scientist Dr. John Wolfe reports.
22:44Forty-four Jovian radii, we had the indication of very strange plasma distribution.
22:52We're taking back with us to our laboratories data which essentially are puzzling to us
22:59and will take a long time to work out.
23:03Some points are clear.
23:07The whole Jupiter system is heavier than we thought by about the weight of two Earth moons.
23:14Io has a thin atmosphere, thus Jupiter's four large moons probably all have atmospheres.
23:23Seeing relatively abrupt decreases in the field magnitude to much lower values.
23:29A compass on Jupiter would point to the south pole instead of the north pole.
23:36The infrared experiment successfully mapped Jupiter's heat in fine detail.
23:41The planet gives off more than twice as much heat as it receives from the sun.
23:47Why?
23:48Possibly its enormous gravity makes it contract like a slow motion star.
23:55The white belts are cooler and therefore higher bands of clouds stretched around basically
24:00darker colored material below.
24:04Also the night side and the day side appear the same temperature.
24:09Studies like these flash out to the world.
24:16To experimenters, some of the most interesting findings concern Jupiter's radiation belts
24:21and magnetic field.
24:23Pioneer first broke into the magnetic field an incredible four million miles in front
24:28of the planet.
24:30Because of the pressure of the solar wind, this field streams out much farther behind
24:35Jupiter.
24:38Closer in, Pioneer indicates that Jupiter's intense radiation belts wobble up and down
24:44around a magnetic center some 10,000 miles from the center of the planet.
24:50In brief, Jupiter is much different from Earth and much more complex than researchers imagined.
24:56However, Pioneer proved that a spacecraft could survive the radiation.
25:05Another encounter, the data tapes for the imaging experiment go to the University of
25:10Arizona for computer enhancement.
25:15In a meticulous process, millions of data points are juggled up and down the scale.
25:21And what emerges is a portrait of Jupiter to challenge the most imaginative artist.
25:32The Pioneers, first to brave this land of giants, first to fly forever among the lonely
25:39and endless stars of our galaxy, carry mankind's message, we're on our way.
25:49Theory holds that Jupiter is so big and so far from the sun that the huge planet retains
25:56most of the material from which it was formed about four and one half billion years ago.
26:02Scientists think that beneath the clouds, Jupiter is an ocean of mostly liquid hydrogen.
26:08Theory says that above the ocean is a 600 mile high, mostly hydrogen atmosphere.
26:15Jovian clouds also contain water, ammonia, and methane.
26:20Between very cold cloud tops and the very hot interior are probably regions of Earth's
26:26normal temperatures.
26:29Jupiter's lightning could be a catalyst in the formation of organic compounds in these
26:34regions.
26:35During our next program, Jupiter, a clearer picture, we will see how NASA plans to send
26:41the Galileo mission to Jupiter in 1986.
26:45Galileo, launched from a shuttle by the Lewis Managed Centaur, will orbit the planet and
26:51send a probe into the clouds.
26:54We will also see the very sharp pictures which Voyager showed us of Jupiter and its moons.
27:01This is Larry Ross saying goodbye from NASA's Lewis Research Center in Cleveland, Ohio.