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- From: leech@mahler.cs.unc.edu (Jon Leech)
- Newsgroups: sci.space,news.answers
- Subject: Space FAQ 10/15 - Planetary Probe History
- Keywords: Frequently Asked Questions
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- Date: 2 Dec 92 17:44:13 GMT
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-
- PLANETARY PROBES - HISTORICAL MISSIONS
-
- This section was lightly adapted from an original posting by Larry Klaes
- (klaes@verga.enet.dec.com), mostly minor formatting changes. Matthew
- Wiener (weemba@libra.wistar.upenn.edu) contributed the section on
- Voyager, and the section on Sakigake was obtained from ISAS material
- posted by Yoshiro Yamada (yamada@yscvax.ysc.go.jp).
-
- US PLANETARY MISSIONS
-
-
- MARINER (VENUS, MARS, & MERCURY FLYBYS AND ORBITERS)
-
- MARINER 1, the first U.S. attempt to send a spacecraft to Venus, failed
- minutes after launch in 1962. The guidance instructions from the ground
- stopped reaching the rocket due to a problem with its antenna, so the
- onboard computer took control. However, there turned out to be a bug in
- the guidance software, and the rocket promptly went off course, so the
- Range Safety Officer destroyed it. Although the bug is sometimes claimed
- to have been an incorrect FORTRAN DO statement, it was actually a
- transcription error in which the bar (indicating smoothing) was omitted
- from the expression "R-dot-bar sub n" (nth smoothed value of derivative
- of radius). This error led the software to treat normal minor variations
- of velocity as if they were serious, leading to incorrect compensation.
-
- MARINER 2 became the first successful probe to flyby Venus in December
- of 1962, and it returned information which confirmed that Venus is a
- very hot (800 degrees Fahrenheit, now revised to 900 degrees F.) world
- with a cloud-covered atmosphere composed primarily of carbon dioxide
- (sulfuric acid was later confirmed in 1978).
-
- MARINER 3, launched on November 5, 1964, was lost when its protective
- shroud failed to eject as the craft was placed into interplanetary
- space. Unable to collect the Sun's energy for power from its solar
- panels, the probe soon died when its batteries ran out and is now in
- solar orbit. It was intended for a Mars flyby with MARINER 4.
-
- MARINER 4, the sister probe to MARINER 3, did reach Mars in 1965 and
- took the first close-up images of the Martian surface (22 in all) as it
- flew by the planet. The probe found a cratered world with an atmosphere
- much thinner than previously thought. Many scientists concluded from
- this preliminary scan that Mars was a "dead" world in both the
- geological and biological sense.
-
- MARINER 5 was sent to Venus in 1967. It reconfirmed the data on that
- planet collected five years earlier by MARINER 2, plus the information
- that Venus' atmospheric pressure at its surface is at least 90 times
- that of Earth's, or the equivalent of being 3,300 feet under the surface
- of an ocean.
-
- MARINER 6 and 7 were sent to Mars in 1969 and expanded upon the work
- done by MARINER 4 four years earlier. However, they failed to take away
- the concept of Mars as a "dead" planet, first made from the basic
- measurements of MARINER 4.
-
- MARINER 8 ended up in the Atlantic Ocean in 1971 when the rocket
- launcher autopilot failed.
-
- MARINER 9, the sister probe to MARINER 8, became the first craft to
- orbit Mars in 1971. It returned information on the Red Planet that no
- other probe had done before, revealing huge volcanoes on the Martian
- surface, as well as giant canyon systems, and evidence that water once
- flowed across the planet. The probe also took the first detailed closeup
- images of Mars' two small moons, Phobos and Deimos.
-
- MARINER 10 used Venus as a gravity assist to Mercury in 1974. The probe
- did return the first close-up images of the Venusian atmosphere in
- ultraviolet, revealing previously unseen details in the cloud cover,
- plus the fact that the entire cloud system circles the planet in four
- Earth days. MARINER 10 eventually made three flybys of Mercury from 1974
- to 1975 before running out of attitude control gas. The probe revealed
- Mercury as a heavily cratered world with a mass much greater than
- thought. This would seem to indicate that Mercury has an iron core which
- makes up 75 percent of the entire planet.
-
-
- PIONEER (MOON, SUN, VENUS, JUPITER, and SATURN FLYBYS AND ORBITERS)
-
- PIONEER 1 through 3 failed to meet their main objective - to photograph
- the Moon close-up - but they did reach far enough into space to provide
- new information on the area between Earth and the Moon, including new
- data on the Van Allen radiation belts circling Earth. All three craft
- had failures with their rocket launchers. PIONEER 1 was launched on
- October 11, 1958, PIONEER 2 on November 8, and PIONEER 3 on December 6.
-
- PIONEER 4 was a Moon probe which missed the Moon and became the first
- U.S. spacecraft to orbit the Sun in 1959. PIONEER 5 was originally
- designed to flyby Venus, but the mission was scaled down and it instead
- studied the interplanetary environment between Venus and Earth out to
- 36.2 million kilometers in 1960, a record until MARINER 2. PIONEER 6
- through 9 were placed into solar orbit from 1965 to 1968: PIONEER 6, 7,
- and 8 are still transmitting information at this time. PIONEER E (would
- have been number 10) suffered a launch failure in 1969.
-
- PIONEER 10 became the first spacecraft to flyby Jupiter in 1973. PIONEER
- 11 followed it in 1974, and then went on to become the first probe to
- study Saturn in 1979. Both vehicles should continue to function through
- 1995 and are heading off into interstellar space, the first craft ever
- to do so.
-
- PIONEER Venus 1 (1978) (also known as PIONEER Venus Orbiter, or PIONEER
- 12) burned up in the Venusian atmosphere on October 8, 1992. PVO made
- the first radar studies of the planet's surface via probe. PIONEER Venus
- 2 (also known as PIONEER 13) sent four small probes into the atmosphere
- in December of 1978. The main spacecraft bus burned up high in the
- atmosphere, while the four probes descended by parachute towards the
- surface. Though none were expected to survive to the surface, the Day
- probe did make it and transmitted for 67.5 minutes on the ground before
- its batteries failed.
-
-
- RANGER (LUNAR LANDER AND IMPACT MISSIONS)
-
- RANGER 1 and 2 were test probes for the RANGER lunar impact series. They
- were meant for high Earth orbit testing in 1961, but rocket problems
- left them in useless low orbits which quickly decayed.
-
- RANGER 3, launched on January 26, 1962, was intended to land an
- instrument capsule on the surface of the Moon, but problems during the
- launch caused the probe to miss the Moon and head into solar orbit.
- RANGER 3 did try to take some images of the Moon as it flew by, but the
- camera was unfortunately aimed at deep space during the attempt.
-
- RANGER 4, launched April 23, 1962, had the same purpose as RANGER 3, but
- suffered technical problems enroute and crashed on the lunar farside,
- the first U.S. probe to reach the Moon, albeit without returning data.
-
- RANGER 5, launched October 18, 1962 and similar to RANGER 3 and 4, lost
- all solar panel and battery power enroute and eventually missed the Moon
- and drifted off into solar orbit.
-
- RANGER 6 through 9 had more modified lunar missions: They were to send
- back live images of the lunar surface as they headed towards an impact
- with the Moon. RANGER 6 failed this objective in 1964 when its cameras
- did not operate. RANGER 7 through 9 performed well, becoming the first
- U.S. lunar probes to return thousands of lunar images through 1965.
-
-
- LUNAR ORBITER (LUNAR SURFACE PHOTOGRAPHY)
-
- LUNAR ORBITER 1 through 5 were designed to orbit the Moon and image
- various sites being studied as landing areas for the manned APOLLO
- missions of 1969-1972. The probes also contributed greatly to our
- understanding of lunar surface features, particularly the lunar farside.
- All five probes of the series, launched from 1966 to 1967, were
- essentially successful in their missions. They were the first U.S.
- probes to orbit the Moon. All LOs were eventually crashed into the lunar
- surface to avoid interference with the manned APOLLO missions.
-
-
- SURVEYOR (LUNAR SOFT LANDERS)
-
- The SURVEYOR series were designed primarily to see if an APOLLO lunar
- module could land on the surface of the Moon without sinking into the
- soil (before this time, it was feared by some that the Moon was covered
- in great layers of dust, which would not support a heavy landing
- vehicle). SURVEYOR was successful in proving that the lunar surface was
- strong enough to hold up a spacecraft from 1966 to 1968.
-
- Only SURVEYOR 2 and 4 were unsuccessful missions. The rest became the
- first U.S. probes to soft land on the Moon, taking thousands of images
- and scooping the soil for analysis. APOLLO 12 landed 600 feet from
- SURVEYOR 3 in 1969 and returned parts of the craft to Earth. SURVEYOR 7,
- the last of the series, was a purely scientific mission which explored
- the Tycho crater region in 1968.
-
-
- VIKING (MARS ORBITERS AND LANDERS)
-
- VIKING 1 was launched from Cape Canaveral, Florida on August 20, 1975 on
- a TITAN 3E-CENTAUR D1 rocket. The probe went into Martian orbit on June
- 19, 1976, and the lander set down on the western slopes of Chryse
- Planitia on July 20, 1976. It soon began its programmed search for
- Martian micro-organisms (there is still debate as to whether the probes
- found life there or not), and sent back incredible color panoramas of
- its surroundings. One thing scientists learned was that Mars' sky was
- pinkish in color, not dark blue as they originally thought (the sky is
- pink due to sunlight reflecting off the reddish dust particles in the
- thin atmosphere). The lander set down among a field of red sand and
- boulders stretching out as far as its cameras could image.
-
- The VIKING 1 orbiter kept functioning until August 7, 1980, when it ran
- out of attitude-control propellant. The lander was switched into a
- weather-reporting mode, where it had been hoped it would keep
- functioning through 1994; but after November 13, 1982, an errant command
- had been sent to the lander accidentally telling it to shut down until
- further orders. Communication was never regained again, despite the
- engineers' efforts through May of 1983.
-
- An interesting side note: VIKING 1's lander has been designated the
- Thomas A. Mutch Memorial Station in honor of the late leader of the
- lander imaging team. The National Air and Space Museum in Washington,
- D.C. is entrusted with the safekeeping of the Mutch Station Plaque until
- it can be attached to the lander by a manned expedition.
-
- VIKING 2 was launched on September 9, 1975, and arrived in Martian orbit
- on August 7, 1976. The lander touched down on September 3, 1976 in
- Utopia Planitia. It accomplished essentially the same tasks as its
- sister lander, with the exception that its seisometer worked, recording
- one marsquake. The orbiter had a series of attitude-control gas leaks in
- 1978, which prompted it being shut down that July. The lander was shut
- down on April 12, 1980.
-
- The orbits of both VIKING orbiters should decay around 2025.
-
-
- VOYAGER (OUTER PLANET FLYBYS)
-
- VOYAGER 1 was launched September 5, 1977, and flew past Jupiter on March
- 5, 1979 and by Saturn on November 13, 1980. VOYAGER 2 was launched
- August 20, 1977 (before VOYAGER 1), and flew by Jupiter on August 7,
- 1979, by Saturn on August 26, 1981, by Uranus on January 24, 1986, and
- by Neptune on August 8, 1989. VOYAGER 2 took advantage of a rare
- once-every-189-years alignment to slingshot its way from outer planet to
- outer planet. VOYAGER 1 could, in principle, have headed towards Pluto,
- but JPL opted for the sure thing of a Titan close up.
-
- Between the two probes, our knowledge of the 4 giant planets, their
- satellites, and their rings has become immense. VOYAGER 1&2 discovered
- that Jupiter has complicated atmospheric dynamics, lightning and
- aurorae. Three new satellites were discovered. Two of the major
- surprises were that Jupiter has rings and that Io has active sulfurous
- volcanoes, with major effects on the Jovian magnetosphere.
-
- When the two probes reached Saturn, they discovered over 1000 ringlets
- and 7 satellites, including the predicted shepherd satellites that keep
- the rings stable. The weather was tame compared with Jupiter: massive
- jet streams with minimal variance (a 33-year great white spot/band cycle
- is known). Titan's atmosphere was smoggy. Mimas' appearance was
- startling: one massive impact crater gave it the Death Star appearance.
- The big surprise here was the stranger aspects of the rings. Braids,
- kinks, and spokes were both unexpected and difficult to explain.
-
- VOYAGER 2, thanks to heroic engineering and programming efforts,
- continued the mission to Uranus and Neptune. Uranus itself was highly
- monochromatic in appearance. One oddity was that its magnetic axis was
- found to be highly skewed from the already completely skewed rotational
- axis, giving Uranus a peculiar magnetosphere. Icy channels were found on
- Ariel, and Miranda was a bizarre patchwork of different terrains. 10
- satellites and one more ring were discovered.
-
- In contrast to Uranus, Neptune was found to have rather active weather,
- including numerous cloud features. The ring arcs turned out to be bright
- patches on one ring. Two other rings, and 6 other satellites, were
- discovered. Neptune's magnetic axis was also skewed. Triton had a
- canteloupe appearance and geysers. (What's liquid at 38K?)
-
- The two VOYAGERs are expected to last for about two more decades. Their
- on-target journeying gives negative evidence about possible planets
- beyond Pluto. Their next major scientific discovery should be the
- location of the heliopause.
-
-
- SOVIET PLANETARY MISSIONS
-
- Since there have been so many Soviet probes to the Moon, Venus, and
- Mars, I will highlight only the primary missions:
-
-
- SOVIET LUNAR PROBES
-
- LUNA 1 - Lunar impact attempt in 1959, missed Moon and became first
- craft in solar orbit.
- LUNA 2 - First craft to impact on lunar surface in 1959.
- LUNA 3 - Took first images of lunar farside in 1959.
- ZOND 3 - Took first images of lunar farside in 1965 since LUNA 3. Was
- also a test for future Mars missions.
- LUNA 9 - First probe to soft land on the Moon in 1966, returned images
- from surface.
- LUNA 10 - First probe to orbit the Moon in 1966.
- LUNA 13 - Second successful Soviet lunar soft landing mission in 1966.
- ZOND 5 - First successful circumlunar craft. ZOND 6 through 8
- accomplished similar missions through 1970. The probes were
- unmanned tests of a manned orbiting SOYUZ-type lunar vehicle.
- LUNA 16 - First probe to land on Moon and return samples of lunar soil
- to Earth in 1970. LUNA 20 accomplished similar mission in
- 1972.
- LUNA 17 - Delivered the first unmanned lunar rover to the Moon's
- surface, LUNOKHOD 1, in 1970. A similar feat was accomplished
- with LUNA 21/LUNOKHOD 2 in 1973.
- LUNA 24 - Last Soviet lunar mission to date. Returned soil samples in
- 1976.
-
-
- SOVIET VENUS PROBES
-
- VENERA 1 - First acknowledged attempt at Venus mission. Transmissions
- lost enroute in 1961.
- VENERA 2 - Attempt to image Venus during flyby mission in tandem with
- VENERA 3. Probe ceased transmitting just before encounter in
- February of 1966. No images were returned.
- VENERA 3 - Attempt to place a lander capsule on Venusian surface.
- Transmissions ceased just before encounter and entire probe
- became the first craft to impact on another planet in 1966.
- VENERA 4 - First probe to successfully return data while descending
- through Venusian atmosphere. Crushed by air pressure before
- reaching surface in 1967. VENERA 5 and 6 mission profiles
- similar in 1969.
- VENERA 7 - First probe to return data from the surface of another planet
- in 1970. VENERA 8 accomplished a more detailed mission in
- 1972.
- VENERA 9 - Sent first image of Venusian surface in 1975. Was also the
- first probe to orbit Venus. VENERA 10 accomplished similar
- mission.
- VENERA 13 - Returned first color images of Venusian surface in 1982.
- VENERA 14 accomplished similar mission.
- VENERA 15 - Accomplished radar mapping with VENERA 16 of sections of
- planet's surface in 1983 more detailed than PVO.
- VEGA 1 - Accomplished with VEGA 2 first balloon probes of Venusian
- atmosphere in 1985, including two landers. Flyby buses went on
- to become first spacecraft to study Comet Halley close-up in
- March of 1986.
-
-
- SOVIET MARS PROBES
-
- MARS 1 - First acknowledged Mars probe in 1962. Transmissions ceased
- enroute the following year.
- ZOND 2 - First possible attempt to place a lander capsule on Martian
- surface. Probe signals ceased enroute in 1965.
- MARS 2 - First Soviet Mars probe to land - albeit crash - on Martian
- surface. Orbiter section first Soviet probe to circle the Red
- Planet in 1971.
- MARS 3 - First successful soft landing on Martian surface, but lander
- signals ceased after 90 seconds in 1971.
- MARS 4 - Attempt at orbiting Mars in 1974, braking rockets failed to
- fire, probe went on into solar orbit.
- MARS 5 - First fully successful Soviet Mars mission, orbiting Mars in
- 1974. Returned images of Martian surface comparable to U.S.
- probe MARINER 9.
- MARS 6 - Landing attempt in 1974. Lander crashed into the surface.
- MARS 7 - Lander missed Mars completely in 1974, went into a solar orbit
- with its flyby bus.
- PHOBOS 1 - First attempt to land probes on surface of Mars' largest
- moon, Phobos. Probe failed enroute in 1988 due to
- human/computer error.
- PHOBOS 2 - Attempt to land probes on Martian moon Phobos. The probe did
- enter Mars orbit in early 1989, but signals ceased one week
- before scheduled Phobos landing.
-
- While there has been talk of Soviet Jupiter, Saturn, and even
- interstellar probes within the next thirty years, no major steps have
- yet been taken with these projects. More intensive studies of the Moon,
- Mars, Venus, and various comets have been planned for the 1990s, and a
- Mercury mission to orbit and land probes on the tiny world has been
- planned for 2003. How the many changes in the former Soviet Union (now
- the Commonwealth of Independent States) will affect the future of their
- space program remains to be seen.
-
-
- JAPANESE PLANETARY MISSIONS
-
- SAKIGAKE (MS-T5) was launched from the Kagoshima Space Center by ISAS on
- January 8 1985, and approached Halley's Comet within about 7 million km
- on March 11, 1986. The spacecraft is carrying three instru- ments to
- measure interplanetary magnetic field/plasma waves/solar wind, all of
- which work normally now, so ISAS made an Earth swingby by Sakigake on
- January 8, 1992 into an orbit similar to the earth's. The closest
- approach was at 23h08m47s (JST=UTC+9h) on January 8, 1992. The
- geocentric distance was 88,997 km. This is the first planet-swingby for
- a Japanese spacecraft.
-
- During the approach, Sakigake observed the geotail. Some geotail
- passages will be scheduled in some years hence. The second Earth-swingby
- will be on June 14, 1993 (at 40 Re(Earth's radius)), and the third
- October 28, 1994 (at 86 Re).
-
-
- PLANETARY MISSION REFERENCES
-
- I also recommend reading the following works, categorized in three
- groups: General overviews, specific books on particular space missions,
- and periodical sources on space probes. This list is by no means
- complete; it is primarily designed to give you places to start your
- research through generally available works on the subject. If anyone can
- add pertinent works to the list, it would be greatly appreciated.
-
- Though naturally I recommend all the books listed below, I think it
- would be best if you started out with the general overview books, in
- order to give you a clear idea of the history of space exploration in
- this area. I also recommend that you pick up some good, up-to-date
- general works on astronomy and the Sol system, to give you some extra
- background. Most of these books and periodicals can be found in any good
- public and university library. Some of the more recently published works
- can also be purchased in and/or ordered through any good mass- market
- bookstore.
-
- General Overviews (in alphabetical order by author):
-
- J. Kelly Beatty et al, THE NEW SOLAR SYSTEM, 1990.
-
- Merton E. Davies and Bruce C. Murray, THE VIEW FROM SPACE:
- PHOTOGRAPHIC EXPLORATION OF THE PLANETS, 1971
-
- Kenneth Gatland, THE ILLUSTRATED ENCYCLOPEDIA OF SPACE
- TECHNOLOGY, 1990
-
- Kenneth Gatland, ROBOT EXPLORERS, 1972
-
- R. Greeley, PLANETARY LANDSCAPES, 1987
-
- Douglas Hart, THE ENCYCLOPEDIA OF SOVIET SPACECRAFT, 1987
-
- Nicholas L. Johnson, HANDBOOK OF SOVIET LUNAR AND PLANETARY
- EXPLORATION, 1979
-
- Clayton R. Koppes, JPL AND THE AMERICAN SPACE PROGRAM: A
- HISTORY OF THE JET PROPULSION LABORATORY, 1982
-
- Richard S. Lewis, THE ILLUSTRATED ENCYCLOPEDIA OF THE
- UNIVERSE, 1983
-
- Mark Littman, PLANETS BEYOND: DISCOVERING THE OUTER SOLAR
- SYSTEM, 1988
-
- Eugene F. Mallove and Gregory L. Matloff, THE STARFLIGHT
- HANDBOOK: A PIONEER'S GUIDE TO INTERSTELLAR TRAVEL, 1989
-
- Frank Miles and Nicholas Booth, RACE TO MARS: THE MARS
- FLIGHT ATLAS, 1988
-
- Bruce Murray, JOURNEY INTO SPACE, 1989
-
- Oran W. Nicks, FAR TRAVELERS, 1985 (NASA SP-480)
-
- James E. Oberg, UNCOVERING SOVIET DISASTERS: EXPLORING THE
- LIMITS OF GLASNOST, 1988
-
- Carl Sagan, COMET, 1986
-
- Carl Sagan, THE COSMIC CONNECTION, 1973
-
- Carl Sagan, PLANETS, 1969 (LIFE Science Library)
-
- Arthur Smith, PLANETARY EXPLORATION: THIRTY YEARS OF UNMANNED
- SPACE PROBES, 1988
-
- Andrew Wilson, (JANE'S) SOLAR SYSTEM LOG, 1987
-
- Specific Mission References:
-
- Charles A. Cross and Patrick Moore, THE ATLAS OF MERCURY, 1977
- (The MARINER 10 mission to Venus and Mercury, 1973-1975)
-
- Joel Davis, FLYBY: THE INTERPLANETARY ODYSSEY OF VOYAGER 2, 1987
-
- Irl Newlan, FIRST TO VENUS: THE STORY OF MARINER 2, 1963
-
- Margaret Poynter and Arthur L. Lane, VOYAGER: THE STORY OF A
- SPACE MISSION, 1984
-
- Carl Sagan, MURMURS OF EARTH, 1978 (Deals with the Earth
- information records placed on VOYAGER 1 and 2 in case the
- probes are found by intelligences in interstellar space,
- as well as the probes and planetary mission objectives
- themselves.)
-
- Other works and periodicals:
-
- NASA has published very detailed and technical books on every space
- probe mission it has launched. Good university libraries will carry
- these books, and they are easily found simply by knowing which mission
- you wish to read about. I recommend these works after you first study
- some of the books listed above.
-
- Some periodicals I recommend for reading on space probes are NATIONAL
- GEOGRAPHIC, which has written articles on the PIONEER probes to Earth's
- Moon Luna and the Jovian planets Jupiter and Saturn, the RANGER,
- SURVEYOR, LUNAR ORBITER, and APOLLO missions to Luna, the MARINER
- missions to Mercury, Venus, and Mars, the VIKING probes to Mars, and the
- VOYAGER missions to Jupiter, Saturn, Uranus, and Neptune.
-
- More details on American, Soviet, European, and Japanese probe missions
- can be found in SKY AND TELESCOPE, ASTRONOMY, SCIENCE, NATURE, and
- SCIENTIFIC AMERICAN magazines. TIME, NEWSWEEK, and various major
- newspapers can supply not only general information on certain missions,
- but also show you what else was going on with Earth at the time events
- were unfolding, if that is of interest to you. Space missions are
- affected by numerous political, economic, and climatic factors, as you
- probably know.
-
- Depending on just how far your interest in space probes will go, you
- might also wish to join The Planetary Society, one of the largest space
- groups in the world dedicated to planetary exploration. Their
- periodical, THE PLANETARY REPORT, details the latest space probe
- missions. Write to The Planetary Society, 65 North Catalina Avenue,
- Pasadena, California 91106 USA.
-
- Good luck with your studies in this area of space exploration. I
- personally find planetary missions to be one of the more exciting areas
- in this field, and the benefits human society has and will receive from
- it are incredible, with many yet to be realized.
-
- Larry Klaes klaes@verga.enet.dec.com
-
-
- NEXT: FAQ #11/15 - Upcoming planetary probes - missions and schedules
-