Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Sat, 22 Jun 91 05:55:09 -0400 (EDT) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 22 Jun 91 05:55:04 -0400 (EDT) Subject: SPACE Digest V13 #684 SPACE Digest Volume 13 : Issue 684 Today's Topics: Re: Missing the point about tethers (was Re: SPACE Digest V13 #541) Information sources for frequent space questions (2 of n) Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 2 Jun 91 00:56:56 GMT From: agate!spool.mu.edu!think.com!rpi!news-server.csri.toronto.edu!utgpu!utzoo!utdoe!torag!w-dnes!waltdnes@ucbvax.Berkeley.EDU (Walter Dnes ) Subject: Re: Missing the point about tethers (was Re: SPACE Digest V13 #541) wreck@fmsrl7.UUCP (Ron Carter) writes: > In article waltdnes@w-dnes.UUCP (Walter Dnes) write ... > >assume that the first tether is a 1-meter-thick cable 500km long. > > What do you need a 1 meter thick cable for? And why 500 km? There are times when it's best to admit that I've goofed and cut my losses. I'll admit that when I jumped into this thread, I wasn't familiar with the concept of tether-tapering. The assumption of a non-tapered tether led to some ridiculous results in my calculations. I apologize for wasting bandwidth. I'll admit that tethers are theoretically possible. There will obviously be teething problems, as with any new technology. Assuming that we learn how to make properly tapered cables of sufficient length, the only question is whether the final operating version will result in sufficient energy savings to pay for itself. As for "beanstalks", I stand by my message of May 31. There are severe *PRACTICAL* challenges which look very daunting at the present moment. Walter Dnes ------------------------- waltdnes@w-dnes.guild.org 73710.3066@compuserve.com ------------------------------ Date: 2 Jun 91 11:32:07 GMT From: data.nas.nasa.gov!amelia!eugene@eos.arc.nasa.gov (Eugene N. Miya) Subject: Information sources for frequent space questions (2 of n) Subject: Planetary Probe posting for Frequently Asked Questions XXX asked the following questions about these planetary space probes: >> Viking 1,2 1975 Still sending any signals? >> If not, when did they stop? 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 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. The next United States Mars mission will be the Mars Observer, scheduled for launch in 1992. Although there are no definite U.S. Mars probe plans after that, some possibilities are a lander which will return samples of Martian soil to Earth (this may be a cooperative project with the Soviets), and a rover/walker vehicle, in preparation for manned missions, which may also be international in scope. >> Mariner 1,2 1962 Did we get any data? MARINER 1, the first U.S. attempt to send a spacecraft to Venus, was destroyed in 1962 over the Atlantic Ocean by the Range Safety Officer when its rocket veered off course due to a program command failure. 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 Farenheit, now revised to 900 degrees F.) world with a cloud-covered atmosphere composed primarily of carbon dioxide (sulfuric acid was later confirmed in 1973). >> 3-7 1963+ Do we even know where they are? 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. 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. It is now in solar orbit. MARINER 5 was sent to Venus in 1967, and 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. >> 8 Crashed in the ocean right? MARINER 8 ended up in the Atlantic Ocean in 1971 when the rocket launcher autopilot failed. >> 9 1971 What was the mission? 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, such as reveal 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 moon, Phobos and Deimos. >> 10 1973 Venus. Any data? 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. >> ?? That's all of them Right? Technically, yes, although VOYAGER 1 and 2 were originally going to be part of the MARINER series (11 and 12), but their names were changed partly to spark new public interest in the program, plus the fact that NASA also felt these vehicles were different in both design and mission scope from the MARINER craft before them to warrant a new designation. >> Pioneer 1-3 Failed moon trajectories? Although PIONEER 1 through 3 did fail to meet their main objective, to photograph the Moon close-up, 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. >> 4-9 All Moon related? 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 33 million miles in 1960, a record until MARINER 2. PIONEER 6 through 9 were placed into solar orbit from 1965 to 1968: PIONEER 6 and 8 are still transmitting information at this time. PIONEER E (would have been 10) suffered a launch failure in 1969. >> 10,11 Jupiter,Saturn Still operating? 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 are still functioning and are heading off into interstellar space, the first craft to do so. >> Pioneer >> Venus 1 1978 Where are they now? How do you know? >> Venus 2 Probes released? What about them? PIONEER Venus 1 (also known as PIONEER Venus Orbiter, or PIONEER 12) is still orbiting Venus and returning data to Earth. It is expected to enter the Venusian atmosphere and burn up by 1991. 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 minutes on the ground before succumbing to the intense surface heat. I only know what NASA tells me. :^) >> Ranger 3-9 1965+ All Moon related? Any data coming in? 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 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 also contained a capsule lander, but it too had launch problems that forced it to miss the Moon and go into solar orbit. RANGER 6 through 9 were 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, but RANGER 7 through 9 performed well, returning thousands of lunar images through 1965, the first U.S. Moon probes to do so. >> Lunar Orbiter ???? What was this for? 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 also the first U.S. probes to orbit the Moon. >> Surveyor 1968 Just for landing site research? 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. 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. >> SOVIET PROBES: Any info at all would be interesting. >> Luna >> Venera >> Mars >> Others? Since there have been so many Soviet probes to the Moon, Venus, and Mars, I will highlight only the primary missions: Moon - 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 SOYUZ-type lunar vehicle. The project was abandoned in 1975. 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. Venus - VENERA 1 - First acknowledged attempt at Venus mission. Transmissions lost enroute in 1961. 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 similar 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 1986. Mars - 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 Mars, Venus, and various comets are planned for the 1990s, and even a Mercury mission to orbit and land probes on the tiny world is planned for 2003. 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, 1981 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@advax.dec.com ------------------------------ End of SPACE Digest V13 #684 *******************