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神经网络昆斯林的新闻组分类2006

        Unfortunately for Venus exploration, plans began to change in
    the Soviet Union.  In 1986 the Soviets decided to reroute the VESTA
    mission to the red planet Mars instead of Venus, keeping the comet
    and planetoid aspects intact.  By this time in the Soviet space 
    program interest was focusing on Mars.  Already under construction 
    was an entirely new probe design called PHOBOS.  Two members of this 
    class were planned to leave Earth in 1988 and orbit Mars the next 
    year.  PHOBOS 1 and 2 would then place the first instruments on
    Mars' largest moon, Phobos. 

        All this was a prelude to even more advanced Mars expeditions,
    including balloon probes, rovers, soil sample return craft, and 
    eventually human explorers in the early Twenty-First Century.
    The environment of Venus was just too hostile for any serious
    consideration of human colonization in the near future.

        But things began to look bleak for Soviet Venus and Mars
    exploration.  Both PHOBOS probes failed to complete their missions,
    one losing contact on the way to the Red Planet in 1988 and the other
    going silent in Mars orbit just one week before the planned moon
    landing in March of 1989. 

        In 1989 a plan was devised for a Venus orbiter to drop eight to
    ten penetrators around the planet in 1998.  Several years later the
    mission launch date was moved to the year 2005 and has now been put 
    on indefinite hold.  No other official Soviet missions to Venus have
    since been put forth, a sad commentary after twenty-five years of
    continuous robotic exploration of the planet. 

        During the late 1980s a drastic political and economic change
    was taking over the Soviet Union.  President Mikhail Gorbachev began 
    to "open up" his nation to the benefits of increased cooperation with 
    the rest of the nations, particularly those in the West.  While the 
    culture became less oppressive than in the past, the economy was taking 
    a very rough ride as it also underwent the effects of a "free market".

        These effects hit everywhere, including the space program.
    Missions at all levels were cut back.  The Soviets began making
    almost desperate attempts to cooperate with other space-faring
    nations either to keep their remaining programs alive or just to 
    make money.  

        In early 1992 it was reported that the Soviets were offering for 
    sale several fully-equipped VENERAs they had in storage for the price 
    of 1.6 million dollars each, an incredibly low price for any planetary 
    probe.  No nation took them up on the bargain.  Meanwhile the United 
    States was gearing up for new Venus missions of their own.

        MAGELLAN and GALILEO 

        The U.S. reactivated their long-dormant planetary exploration
    with the launch of the Space Shuttle ATLANTIS on May 4, 1989.
    Aboard the Shuttle was the MAGELLAN spacecraft, a combination of
    spare parts from other U.S. probes designed to make the most 
    detailed and complete radar-mapping of Venus in history.  When
    MAGELLAN reached the second world in August of 1990, it would be
    able to map almost the entire planet down to a resolution of 108
    meters (360 feet), surpassing the abilities of VENERA 15 and 16.

        In the interim another American probe was launched from a Space 
    Shuttle which would make a quick flyby of Venus on its way to orbit 
    the giant planet Jupiter in 1995.  On October 18, 1989, the Shuttle 
    ATLANTIS released its second unmanned planetary probe into space, 
    named GALILEO after the famous Italian astronomer who discovered the 
    probe's primary target's major moons in 1610.

        In the absence of a powerful enough booster to send GALILEO on
    a direct flight to the Jovian planet, the probe was sent around
    Venus and Earth several times to build up enough speed to reach
    Jupiter.  As a result, Venus became GALILEO's first planetary
    goal in February of 1990.  The probe radioed back images of the
    planet's swirling clouds and further indications of lightning in
    that violent atmosphere.

        On the Drawing Boards

        With the incredible success of MAGELLAN in the last few years,
    new plans have been laid out for further journeys to Venus.  Scien-
    tists in the U.S. have talked to space scientists in the former Soviet 
    Union - now the Commonwealth of Independent States since January 1, 
    1992 - of a cooperative effort to launch new VENERA lander missions 
    within in the next decade.  Japan, India, and the ESA have also
    considered their own Venus missions in the next few decades.

        In February of 1993 NASA came up with several new Venus projects 
    as part of their Discovery Program for launching inexpensive probes
    throughout the solar system.  For Venus two missions were selected
    for further study:  A Venus Multiprobe Mission involving the landing
    of fourteen small probes over one hemisphere to measure winds, air
    temperature, and pressure; and the Venus Composition Probe, designed
    to study Venus' atmosphere while descending through the thick air
    with the aid of a parachute, much as the Soviets had done since 1967.
    Final project decisions will be made in 1994.

        Humans on Venus      

        Will a human ever be able to stand on the surface of Venus?
    At present the lead-melting temperatures and crushing air pressure
    would be threatening to any Earth life not protected in something
    even tougher than a VENERA lander.  Plans have been looked into
    changing the environment of Venus itself into something more like
    Earth's.  However, it should be noted that any such undertaking
    will require the removal of much of the thick carbon dioxide 
    atmosphere, a major reduction in surface heat, and the ability 
    to speed up the planet's rotation rate to something a bit faster
    than once every 243 Earth days.  Such a project may take centuries
    if not millennia.

        In the meantime efforts should be made to better understand
    Venus as its exists today.  We still have yet to fully know how
    a world so seemingly similar to Earth in many important ways became
    instead such a deadly place.  Will Earth ever suffer this fate?
    Perhaps Venus holds the answers.  Such answers may best be found
    through international cooperation, including the nation which 
    made the first attempts to lift the cloudy veils from Venus.

        Bibliography -

         Barsukov, V. L., Senior Editor, VENUS GEOLOGY, GEOCHEMISTRY, AND 
           GEOPHYSICS: RESEARCH RESULTS FROM THE U.S.S.R., University of
           Arizona Press, Tucson, 1992

         Beatty, J. Kelly, and Andrew Chaikin, Editors, THE NEW SOLAR 
           SYSTEM, Cambridge University Press and Sky Publishing Corp.,
           Cambridge, Massachusetts, 1990

         Burgess, Eric, VENUS: AN ERRANT TWIN, Columbia University Press, 
           New York, 1985

         Burrows, William E., EXPLORING SPACE: VOYAGES IN THE SOLAR
           SYSTEM AND BEYOND, Random House, Inc., New York, 1990

         Chaisson, Eric, and Steve McMillan, ASTRONOMY TODAY, Prentice-
           Hall, Inc., Englewood Cliffs, New Jersey, 1993

         Gatland, Kenneth, THE ILLUSTRATED ENCYCLOPEDIA OF SPACE TECHNOLOGY, 
           Salamander Books, New York, 1989

         Greeley, Ronald, PLANETARY LANDSCAPES, Allen and Unwin, Inc.,
           Winchester, Massachusetts, 1987

         Hart, Douglas, THE ENCYCLOPEDIA OF SOVIET SPACECRAFT, Exeter 
           Books, New York, 1987

         Hartmann, William K., MOONS AND PLANETS (Third Edition), Wadsworth
           Publishing Company, Belmont, California, 1993

         Harvey, Brian, RACE INTO SPACE: THE SOVIET SPACE PROGRAMME, 
           Ellis Howood Limited, Chichester, England, 1988

         Henbest, Nigel, THE PLANETS: PORTRAITS OF NEW WORLDS, Viking
           Penguin Books Ltd., Harmondsworth, Middlesex, England, 1992

         Johnson, Nicholas L., SOVIET SPACE PROGRAMS 1980-1985, Volume
           66 Science and Technology Series, American Astronautical 
           Society, Univelt, Inc., San Diego, California, 1987

         Johnson, Nicholas L., THE SOVIET YEAR IN SPACE 1989/1990, 
           Teledyne Brown Engineering, Colorado Springs, Colorado,
           1990/1991

         Lang, Kenneth R., and Charles A. Whitney, WANDERERS IN SPACE:
           EXPLORATION AND DISCOVERY IN THE SOLAR SYSTEM, Cambridge 
           University Press, New York, 1991

         MAGELLAN: THE UNVEILING OF VENUS, JPL 400-345, March 1989

         Murray, Bruce, Michael C. Malin, and Ronald Greeley, EARTHLIKE
           PLANETS: SURFACES OF MERCURY, VENUS, EARTH, MOON, MARS, W. H.
           Freeman and Company, San Francisco, California, 1981

         Murray, Bruce, JOURNEY INTO SPACE: THE FIRST THREE DECADES OF
           SPACE EXPLORATION, W. W. Norton and Company, New York, 1989

         Newcott, William, "Venus Revealed", NATIONAL GEOGRAPHIC MAGAZINE, 
           Volume 183, Number 2, Washington, D.C., February 1993

         Nicks, Oran W., FAR TRAVELERS: THE EXPLORING MACHINES, NASA 
           SP-480, Washington, D.C., 1985

         Oberg, James Edward, NEW EARTHS: RESTRUCTURING EARTH AND OTHER
           PLANETS, A Meridian Book, New American Library, Inc., New
           York, 1983

         Robertson, Donald F., "Venus - A Prime Soviet Objective" (Parts 
           1/2), SPACEFLIGHT, Volume 34, Numbers 5/6, British Interplanetary
           Society (BIS), London, England, May/June 1992

         Smith, Arthur, PLANETARY EXPLORATION: THIRTY YEARS OF UNMANNED
           SPACE PROBES, Patrick Stephens, Ltd., Wellingborough, Northamp-
           tonshire, England, 1988

         VOYAGE THROUGH THE UNIVERSE: THE NEAR PLANETS, By the Editors
           of Time-Life Books, Inc., Alexandria, Virginia, 1990

         Wilson, Andrew, JANE'S SOLAR SYSTEM LOG, Jane's Publishing, Inc.,
           New York, 1987

        About the Author -

        Larry Klaes, EJASA Editor, is the recipient of the ASA's 1990 
    Meritorious Service Award for his work as Editor of the EJASA since 
    its founding in August of 1989.  Larry also teaches a course on
    Basic Astronomy at the Concord-Carlisle Adult and Community 
    Education Program in Massachusetts.

        Larry is the author of the following EJASA articles:

        "The One Dream Man: Robert H. Goddard, Rocket Pioneer" - August 1989
        "Stopping Space and Light Pollution" - September 1989              
        "The Rocky Soviet Road to Mars" - October 1989
        "Astronomy and the Family" - May 1991  
        "The Soviets and Venus, Part 1" - February 1993
        "The Soviets and Venus, Part 2" - March 1993


      THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC

                          April 1993 - Vol. 4, No. 9

                           Copyright (c) 1993 - ASA