Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v16_4/v16no494.txt

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Date: Wed, 28 Apr 93 05:05:11
From: Space Digest maintainer <[e-mail]>
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Subject: Space Digest V16 #494
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Space Digest                Wed, 28 Apr 93       Volume 16 : Issue 494

Today's Topics:
          Command Loss Timer (Re: Galileo Update - 04/22/93)
          Electronic Journal of the ASA (EJASA) - April 1993
                    Ranking of SPACE mailing list
              Space Station Redesign, JSC Alternative #4
                    Surviving Large Accelerations?
                         Vandalizing the sky

    Welcome to the Space Digest!!  Please send your messages to
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Date: Mon, 26 Apr 1993 19:39:24 GMT
From: Jim Cobban <[e-mail]>
Subject: Command Loss Timer (Re: Galileo Update - 04/22/93)
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Having read in the past about the fail-safe mechanisms on spacecraft, I had
assumed that the Command Loss Timer had that sort of function.  However I
always find disturbing the oxymoron of a "NO-OP" command that does something.
If the command changes the behavior or status of the spacecraft it is not
a "NO-OP" command.

Of course this terminology comes from a Jet Propulsion Laboratory which has
nothing to do with jet propulsion.

--
-------------------------------------------------------------------------------
Jim Cobban   |  [e-mail]                        |  Phone: [phone]
BNR Ltd.     |  bnrgate.bnr.ca!bcars5!jcobban         |  FAX:   [phone]

------------------------------

Date: Mon, 26 Apr 1993 23:18:59 GMT
From: Larry Klaes <[e-mail]>
Subject: Electronic Journal of the ASA (EJASA) - April 1993
Newsgroups: sci.astro,sci.space,sci.misc,sci.geo.geology,alt.sci.planetary

                          THE ELECTRONIC JOURNAL OF
                  THE ASTRONOMICAL SOCIETY OF THE ATLANTIC

                       Volume 4, Number 9 - April 1993

                         ###########################

                              TABLE OF CONTENTS

                         ###########################

          * ASA Membership and Article Submission Information

          * The Soviets and Venus, Part 3 - Larry Klaes

                         ###########################

                         ASA MEMBERSHIP INFORMATION

        The Electronic Journal of the Astronomical Society of the Atlantic
    (EJASA) is published monthly by the Astronomical Society of the
    Atlantic, Incorporated.  The ASA is a non-profit organization dedicated
    to the advancement of amateur and professional astronomy and space
    exploration, as well as the social and educational needs of its members.

        ASA membership application is open to all with an interest in
    astronomy and space exploration.  Members receive the Journal of the
    ASA (hardcopy sent through United States Mail - Not a duplicate of this
    Electronic Journal) and the Astronomical League's REFLECTOR magazine.
    Members may also purchase discount subscriptions to ASTRONOMY and
    SKY & TELESCOPE magazines.

        For information on membership, you may contact the Society at any
    of the following addresses:

        Astronomical Society of the Atlantic (ASA)
        c/o Center for High Angular Resolution Astronomy (CHARA)
        Georgia State University (GSU)
        Atlanta, Georgia  30303
        U.S.A.

        [e-mail]

        ASA BBS: [phone], 300/1200/2400 Baud

        or telephone the Society Recording at [phone] to leave your
    address and/or receive the latest Society news.

        ASA Officers and Council -

        President - Eric Greene
        Vice President - Jeff Elledge
        Secretary - Ingrid Siegert-Tanghe
        Treasurer - Mike Burkhead
        Directors - Becky Long, Tano Scigliano, Bob Vickers
        Council - Bill Bagnuolo, Michele Bagnuolo, Don Barry, Bill Black,
                  Mike Burkhead, Jeff Elledge, Frank Guyton, Larry Klaes,
                  Ken Poshedly, Jim Rouse, Tano Scigliano, John Stauter,
                  Wess Stuckey, Harry Taylor, Gary Thompson, Cindy Weaver,
                  Bob Vickers


                             ARTICLE SUBMISSIONS

        Article submissions to the EJASA on astronomy and space exploration
    are most welcome.  Please send your on-line articles in ASCII format to
    Larry Klaes, EJASA Editor, at the following net addresses or the above
    Society addresses:

        [e-mail]
        or - ...!decwrl!verga.enet.dec.com!klaes
        or - [e-mail]
        or - [e-mail]

        You may also use the above addresses for EJASA back issue requests,
    letters to the editor, and ASA membership information.

        When sending your article submissions, please be certain to include
    either a network or regular mail address where you can be reached, a
    telephone number, and a brief biographical sketch.

        Back issues of the EJASA are also available from the ASA anonymous
    FTP site at chara.gsu.edu (131.96.5.29).  Directory: /pub/ejasa

                                DISCLAIMER

        Submissions are welcome for consideration.  Articles submitted,
    unless otherwise stated, become the property of the Astronomical
    Society of the Atlantic, Incorporated.  Though the articles will not
    be used for profit, they are subject to editing, abridgment, and other
    changes.  Copying or reprinting of the EJASA, in part or in whole, is
    encouraged, provided clear attribution is made to the Astronomical
    Society of the Atlantic, the Electronic Journal, and the author(s).
    Opinions expressed in the EJASA are those of the authors' and not
    necessarily those of the ASA.  This Journal is Copyright (c) 1993
    by the Astronomical Society of the Atlantic, Incorporated.


                             THE SOVIETS AND VENUS
                                     PART 3

                       Copyright (c) 1993 by Larry Klaes

    The author gives permission to any group or individual wishing
    to distribute this article, so long as proper credit is given,
        the author is notified, and the article is reproduced in its
        entirety.

        To the North Pole!

        On June 2 and 7, 1983, two of the Soviet Union's mighty PROTON
    rockets lifted off from the Tyuratam Space Center in the Kazakhstan
    Republic.  Aboard those boosters were a new breed of VENERA probe
    for the planet Venus.

        Designated VENERA 15 and 16, the probes were meant not for landing
    yet more spherical craft on the Venerean surface but to radar map the
    planet in detail from orbit.  To accomplish this task, the basic
    VENERA design was modified in numerous areas.  The central bus core
    was made one meter (39.37 inches) longer to carry the two tons of
    propellant required for braking into orbit, double the fuel carried by
    the VENERA 9 and 10 orbiters eight years earlier.  Extra solar panels
    were added on to give the vehicles more power for handling the large
    amounts of data which would be created by the radar imaging.  The
    dish-shaped communications antennae were also made one meter larger
    to properly transmit this information to Earth.

        Atop the buses, where landers were usually placed, were installed
    the 1.4 by 6-meter (4.62 by 19.8-foot), 300-kilogram (660-pound)
    POLYUS V side-looking radar antennae.  The radar system, possibly a
    terrain-imaging version of the nuclear-powered satellites used by
    the Soviets for Earth ocean surveillance, would be able to map Venus'
    surface at a resolution of one to two kilometers (0.62 to 1.2 miles).

        The Soviet probes' imaging parameters were a vast improvement over
    the United States PIONEER VENUS Orbiter, which could reveal objects
    no smaller than 75 kilometers (45 miles) in diameter.  And while the
    VENERAs' resolution was comparable to that of similar observations
    made by the 300-meter (1,000-foot) Arecibo radio telescope on the
    island of Puerto Rico, the orbiters would be examining the northern
    pole of Venus.  This region was unobtainable by either Arecibo or
    PIONEER VENUS and appeared to contain a number of potentially
    interesting geological features worthy of investigation.

        On October 10, 1983, after an interplanetary journey of 330
    million kilometers (198 million miles) and two mid-course corrections,
    VENERA 15 fired its braking rockets over Venus to place itself in a
    polar orbit 1,000 by 65,000 kilometers (600 by 39,000 miles) around
    the planet, completing one revolution every twenty-four hours.  VENERA
    16 followed suit four days later.  The twin probes thus became Venus'
    first polar-circling spacecraft.

        Radar operations began on October 16 for VENERA 15 and October 20
    for VENERA 16.  For up to sixteen minutes every orbit over the north
    pole, the probes would make a radar sweep of the surface 150 kilometers
    (ninety miles) wide and nine thousand kilometers (5,400 miles) long.
    The craft would then head out to the highest part of their orbits over
    the south pole to recharge their batteries and transmit the data back
    to two large Soviet antennae on Earth.  Each strip of information took
    eight hours to process by computer.  By the end of their main missions
    in July of 1984, the VENERAs had mapped 115 million square kilometers
    (46 million square miles), thirty percent of the entire planet.

        VENERA 15 and 16 revealed that Venus has a surface geology more
    complex than shown by PIONEER VENUS in the late 1970s.  Numerous hills,
    mountains, ridges, valleys, and plains spread across the landscape,
    many of them apparently formed by lava from erupting volcanoes in the
    last one billion years.  In planetary terms this makes the Venerean
    surface rather young.  Hundreds of craters were detected as well, the
    largest of which had to have been created by meteorites (planetoids
    would be a better term here) at least fourteen kilometers (8.4 miles)
    across, due to Venus' very dense atmosphere.

        There were some disagreements between U.S. and Soviet scientists
    on the origins of certain surface features.  For example, the probes'
    owners declared that the 96-kilometer (57.6-mile) wide crater at the
    summit of 10,800-meter (35,640-foot) high Maxwell Montes, the tallest
    mountain on the planet, was the result of a meteorite impact.  American
    scientists, on the other hand, felt the crater was proof that Maxwell
    was a huge volcano sitting on the northern "continent" of Ishtar Terra.

        In any event, the U.S. decided to wait on making verdicts about
    Venus until the arrival of their own radar probe, scheduled for later
    in the decade.  Originally named the Venus Orbiting Imaging Radar
    (VOIR), its initial design was scaled back and the craft was redesig-
    nated the Venus Radar Mapper (VRM).  Eventually the machine would be
    called MAGELLAN, after the Portuguese navigator Ferdinand Magellan
    (circa 1480-1521).  This vehicle would map the entire planet in even
    finer detail than the VENERAs.  For the time, however, the Soviet
    probes maintained that distinction.

        Radar imaging was not the only ability of the VENERAs.  Bolted
    next to the POLYUS V radar antenna were the Omega altimeter and the
    Fourier infrared spectrometer, the latter for measuring the world's
    temperatures.  The majority of the areas covered registered about
    five hundred degrees Celsius (932 degrees Fahrenheit), but a few
    locations were two hundred degrees hotter, possibly indicating
    current volcanic activity.  The probes also found that the clouds
    over the poles were five to eight kilometers (three to 4.8 miles)
    lower than at the equator.  In contrast, the polar air above sixty
    kilometers (thirty-six miles) altitude was five to twenty degrees
    warmer than the equatorial atmosphere at similar heights.

        When the main mapping mission ended in July of 1984, there were
    plans for at least one of the VENERAs to radar image the surface at
    more southernly latitudes.  Unfortunately this idea did not come to
    pass, as the orbiters may not have possessed enough attitude-control
    gas to perform the operation.

        VENERA 15 and 16 ceased transmission in March of 1985, leaving
    the Soviet Institute of Radiotechnology and Electronics with six
    hundred kilometers (360 miles) of radar data tape to sort into an
    atlas of twenty-seven maps of the northern hemisphere of Venus.

        Venus by Balloon

        For years the thick atmosphere of Venus had been a tempting
    target to scientists who wished to explore the planet's mantle of
    air with balloon-borne instruments.  Professor Jacques Blamont of
    the French space agency Centre National d'Etudes Spatiales (CNES)
    had proposed such an idea as far back as 1967, only to have a joint
    French-Soviet balloon mission canceled in 1982.  Nevertheless,
    late in the year 1984, such dreams would eventually come true.

        When two PROTON rockets were sent skyward on December 15 and 21,
    the Soviet Union provided Western observers with the first clear, full
    views of the booster which had been launching every Soviet Venus probe
    since 1975.  This was but one of many firsts for the complex mission.

        The unmanned probes launched into space that December were named
    VEGA 1 and 2, a contraction of the words VENERA and GALLEI - Gallei
    being the Russian word for Halley.  Not only did the spacecraft
    have more than one mission to perform, they also had more than one
    celestial objective to explore, namely the comet Halley.

        This famous periodic traveler was making its latest return to
    the inner regions of the solar system since its last visit in 1910.
    Since it was widely believed that comets are the icy remains from
    the formation of the solar system five billion years ago, scientists
    around the world gave high priority to exploring one of the few such
    bodies which actually come close to Earth.

        Most comets linger in the cold and dark outer fringes of the solar
    system.  Some, like Halley, are perturbed by various forces and fall
    in towards the Sun, where they circle for millennia spewing out ice
    and debris for millions of kilometers from the warmth of each solar
    encounter.

        The Soviet Union, along with the European Space Agency (ESA) and
    Japan's Institute of Space and Astronautical Science (ISAS), did not
    wish to miss out on this first opportunity in human history to make a
    close examination of Halley.  The ESA would be using the cylindrical
    GIOTTO probe to make a dangerously close photographic flyby of the
    comet, while Japan's first deep space craft - SAKIGAKE (Pioneer) and
    SUISEI (Comet) - would view Halley from a much safer distance.

        Scientists in the United States also desired to study the comet
    from the vantage of a space probe, at one time envisioning a vessel
    powered by solar sails or ion engines.  However, government budget
    cuts to NASA canceled the American efforts.  The U.S. would have to
    make do primarily with Earth-based observations and the sharing of
    data from other nations, though an instrument named the Dust Counter
    and Mass Analyzer (DUCMA), designed by Chicago University Professor
    John Simpson, was added on the Soviet mission in May of 1984.

        The Soviets' answer to Halley were the VEGAs.  Instead of building
    an entirely new craft for the mission, the Soviets decided to modify
    their VENERA bus design to encounter the comet while performing an
    advanced Venus mission along the way.  As VEGA 1 and 2 reached Venus,
    the buses would drop off one lander/balloon each and use the mass of
    the shrouded planet to swing them towards comet Halley, much as the
    U.S. probe MARINER 10 used Venus to flyby Mercury eleven years earlier.
    The Soviet craft would then head on to Halley, helping to pinpoint the
    location of the comet's erupting nucleus for the GIOTTO probe to dive
    in only 605 kilometers (363 miles) away in March of 1986.

        As planned, the two VEGAs arrived at Venus in June of 1985.  VEGA
    1 released its payload first on the ninth day of the month, the lander
    making a two-day descent towards the planet.  The craft touched the
    upper atmosphere on the morning of June 11.  Sixty-one kilometers
    (36.6 miles) above the Venerean surface a small container was released
    by the lander, which produced a parachute at 55 kilometers (33 miles)
    altitude.  Thus the first balloon probe ever to explore Venus had
    successfully arrived.

        One kilometer after the opening of the parachute, helium gas was
    pumped into the Teflon-coated plastic balloon, inflating it to a
    diameter of 3.54 meters (11.68 feet).  Dangling on a tether thirteen
    meters (42.9 feet) below was the instrument package, properly known as
    an aerostat.  The top part of the 6.9-kilogram (15.18-pound) aerostat
    consisted of a cone which served as an antenna and tether attachment
    point to the balloon.  Beneath it was the transmitter, electronics,
    and instruments.  Connected at the bottom was a nephelometer for
    measuring cloud particles.  The aerostat was painted with a special
    white finish to keep at bay the corroding mist of sulfuric acid which
    permeated the planet's atmosphere.

        The VEGA 1 balloon was dropped into the night side of Venus just
    north of the equator.  Scientists were concerned that the gas bag
    would burst in the heat of daylight, so they placed it in the darkened
    hemisphere to give the craft as much time as possible to return data.
    This action necessitated that the landers come down in the dark as
    well, effectively removing the camera systems used on previous missions.
    The author wonders, though, if they could have used floodlights similar
    to the ones attached to VENERA 9 and 10 in 1975, when Soviet scientists
    had thought the planet's surface was enshrouded in a perpetual twilight
    due to the permanently thick cloud cover.

        The first balloon transmitted for 46.5 hours right into the day
    hemisphere before its lithium batteries failed, covering 11,600
    kilometers (6,960 miles).  The threat of bursting in the day heat did
    not materialize.  The VEGA 1 balloon was stationed at a 54-kilometer
    (32.4-mile) altitude after dropping ballast at fifty kilometers
    (thirty miles), for this was considered the most active of the three
    main cloud layers reported by PIONEER VENUS in 1978.  Indeed the
    balloon was pushed across the planet at speeds up to 250 kilometers
    (150 miles) per hour.  Strong vertical winds bobbed the craft up and
    down two to three hundred meters (660 to 990 feet) through most of the
    journey.  The layer's air temperature averaged forty degrees Celsius
    (104 degrees Fahrenheit) and pressure was a mere 0.5 Earth atmosphere.
    The nephelometer could find no clear regions in the surrounding clouds.

        Early in the first balloon's flight, the VEGA 1 lander was already
    headed towards the Venerean surface.  Both landers were equipped with
    a soil drill and analyzer similar to the ones carried on VENERA 13
    and 14 in 1982.  However, VEGA 1 would become unable to report the
    composition of the ground at its landing site in Rusalka Planitia, the
    Mermaid Plain north of Aphrodite Terra.  While still ten to fifteen
    minutes away from landing, a timer malfunction caused the drill to
    accidentally begin its programmed activity sixteen kilometers (9.6
    miles) above the surface.

        There was neither any way to shut off the instrument before
    touchdown nor reactivate it after landing.  This was unfortunate not
    only for the general loss of data but also for the fact that most of
    Venus was covered with such smooth low-level lava plains and had never
    before been directly examined.  Nevertheless, the surface temperature
    and pressure was calculated at 468 degrees Celsius (874.4 degrees
    Fahrenheit) and 95 Earth atmospheres respectively during the lander's
    56 minutes of ground transmissions.  A large amount of background
    infrared radiation was also recorded at the site.

        As had been done when the drills and cameras on VENERA 11 and
    12 had failed in December of 1978, the Soviets focused on the data
    returned during the lander's plunge through the atmosphere.  The
    French-Soviet Malachite mass spectrometer detected sulfur, chlorine,
    and possibly phosphorus.  It is the sulfur - possibly from active
    volcanoes - which gives the Venerean clouds their yellowish color.
    The Sigma 3 gas chromatograph found that every cubic meter of air
    between an altitude of 48 and 63 kilometers (28.8 and 37.8 miles)
    contained one milligram (0.015 grain) of sulfuric acid.

        The VEGA 1 data on the overall structure of the cloud decks
    appeared to be at odds with the information from PIONEER VENUS.
    The case was made even stronger by the fact that VEGA 2's results
    nearly matched its twin.  The VEGAs found only two main cloud layers
    instead of the three reported by the U.S. probes.  The layers were
    three to five kilometers (1.8 to 3 miles) thick at altitudes of 50
    and 58 kilometers (30 and 34.8 miles).  The clouds persisted like a
    thin fog until clearing at an altitude of 35 kilometers (21 miles),
    much lower than the PV readings.  One possibility for the discrepan-
    cies may have been radical structural changes in the Venerean air
    over the last seven years.

        When the lander and balloon finally went silent, the last
    functioning part of the VEGA 1 mission, the flyby bus, sailed on
    for a 708 million-kilometer (424.8 million-mile) journey around
    the Sun to become the first probe to meet comet Halley.  On March
    6, 1986, the bus made a 8,890-kilometer (5,334-mile) pass at the
    dark and icy visitor before traveling on in interplanetary space.
    The Soviets had accomplished their first mission to two celestial
    bodies with one space vessel.

        On June 13, VEGA 2 released its lander/balloon payload for
    a two-day fall towards Venus.  Like its duplicate, the VEGA 2
    balloon radioed information back to the twenty antennae tracking
    it on Earth for 46.5 hours before battery failure on the morning
    side of the planet.  During its 11,100-kilometer (6,660-mile)
    flight over Venus, the second balloon entered in a rather still
    environment which became less so twenty hours into the mission.
    After 33 hours mission time the air became even more turbulent
    for a further eight hours.  When the balloon passed over a five-
    kilometer (three-mile) mountain on the "continent" of Aphrodite
    Terra, a powerful downdraft pulled the craft 2.5 kilometers (1.5
    miles) towards the surface.

        Temperature sensors on the VEGA 2 balloon reported that the air
    layer it was moving through was consistently 6.5 degrees Celsius
    (43.7 degrees Fahrenheit) cooler than the area explored by the VEGA 1
    balloon.  This was corroborated by the VEGA 2 lander as it passed
    through the balloon's level.  No positive indications of lightning
    were made by either balloon, and the second aerostat's nephelometer
    failed to function.

        The VEGA 2 lander touched down on the northern edge of Aphrodite
    Terra's western arm on the fifteenth of June, 1,500 kilometers (900
    miles) southeast of VEGA 1.  The lander's resting place was smoother
    than thought, indicating either a very ancient and worn surface or a
    relatively young one covered in fresh lava.  The soil drill was in
    working order and reported a rock type known as anorthosite-troctolite,
    rare on Earth but present in Luna's highlands.  This rock is rich in
    aluminum and silicon but lacking in iron and magnesium.  A high degree
    of sulfur was also present in the soil.  The air around VEGA 2 measured
    463 degrees Celsius (865.4 degrees Fahrenheit) and 91 Earth atmospheres,
    essentially a typical day (or night) on Venus.

        Far above the VEGA 2 lander, its carrier bus sped past Venus at
    a distance of 24,500 kilometers (14,700 miles) and followed its twin
    to comet Halley, making a closer flyby on March 9, 1986 at just 8,030
    kilometers (4,818 miles).  Both probes helped to reveal that the comet
    is a very dark and irregular-shaped mass about fourteen kilometers
    (8.4 miles) across, rotating once every 53 hours, give or take three
    hours.

        Since both VEGA craft were still functioning after their Halley
    encounters, Soviet scientists considered an option to send the
    probes to other celestial objects.  One prime target was the near-
    Earth planetoid 2101 Adonis, which VEGA 2 could pass at a distance
    of six million kilometers (3.6 million miles).  Sadly, the Soviets
    had to back out on the opportunity to become the first nation to fly
    a spacecraft past a planetoid when it was discovered that there was
    not enough maneuvering fuel in the probe to reach Adonis as planned.
    VEGA 1 and 2 were quietly shut down in early 1987.

        Future Plans Diverted

        The impressive VEGA mission had given some scientists numerous
    ideas and hope for even more ambitious expeditions to the second
    world from the Sun.  One example was the VESTA mission, planned for
    the early 1990s.

        This Soviet-French collaboration called for the launch of multiple
    probes on a single PROTON rocket in either 1991 or 1992.  The craft
    would first swing by Venus and drop off several landers and balloon
    probes.  The aerostats would be designed to survive in the planet's
    corrosive atmosphere for up to one month, a large improvement over
    the VEGA balloons' two days.  The mission would then head out to
    investigate several planetoids and comets, including a possible
    landing on Vesta (thus the mission name), the most reflective Main
    Belt planetoid as seen from Earth.

        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

------------------------------

Date: 27 Apr 93 11:41:11 EDT
From: Larry Krumenaker <[e-mail]>
Subject: Ranking of SPACE mailing list

About three weeks ago on the SPACE list, someone was quoting a source on the
relative traffic and rankings of this listserv.  A figure of 88th in
traffic(?) was given.  Unfortunately I did not clip the message and I would
like to know the source of the rankings list.  If anybody still has that
discussion on their disk or knows the source (or is the poster himself!)
I'd appreciate getting that reference.  Being on the road I have temporarily
unsubscribed to the list to cut down mail box stuffing <g> so please reply
via e-mail to [e-mail] OR [e-mail] or I won't get your
answer!

Larry Krumenaker
Odyssey Magazine

------------------------------

Date: Mon, 26 Apr 1993 22:13:11 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Space Station Redesign, JSC Alternative #4
Newsgroups: sci.space

In <[e-mail]> [e-mail] (David B. Mckissock) writes:

>Option "A" - Low Cost Modular Approach
>  -  Human tended capability (as opposed to the old SSF sexist term
>     of man-tended capability)

>Option "B" - Space Station Freedom Derived
>  -  Man-Tended Capability (Griffin has not yet adopted non-sexist
>     language)

>Option C - Single Core Launch Station.

I'll vote for anything where they don't feel constrained to use stupid
and ugly PC phrases to replace words like 'manned'.  If they think
they need to do that, they're more than likely engaging in 'politics
and public relations as usual' rather than seriously wanting to
actually get into space.  So that eliminates Option "A" from the
running.  What do they call a manned station in Option "C"?

[I'm actually about half serious about that.  People should be more
concerned with grammatical correctness and actually getting a working
station than they are with 'Political Correctness' of terminology.]


--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

------------------------------

Date: 26 Apr 93 21:58:51 GMT
From: Eric H Seale <[e-mail]>
Subject: Surviving Large Accelerations?
Newsgroups: sci.space

>Amruth Laxman <[e-mail]> writes:
>> ... humans (and this was published
>> in 1986) have already withstood accelerations of 45g. All this is very
>> long-winded but here's my question finally - Are 45g accelerations in
>> fact humanly tolerable? - with the aid of any mechanical devices of
>> course.

[e-mail] (Lan Pham) writes:
>are you sure 45g is the right number? as far as i know, pilots are
>blackout in dives that exceed 8g - 9g. 45g seems to be out of human
>tolerance. would anybody clarify this please.

Actually, both numbers are correct.  The difference is in the direction
of the acceleration.  For pilots, accelerations tend to be transverse to
the direction you're facing (pulling out from a steep dive, the
acceleration will force blood toward your feet, for instance).  In this
case, you can only put up with about 8 g's even with a pressure suit.

The record for acceleration, though, is measured along "the direction
you're facing" (for lack of a better term).  As I recall, this record
was set in rocket sleds back in the 60's -- and was about 40 g's or so.

Eric Seale
[e-mail]

------------------------------

Date: Tue, 27 Apr 93 09:52:32 PDT
From: "UTADNX::UTDSSA::GREER"@utspan.span.nasa.gov
Subject: Vandalizing the sky

In Space Digest V16 #487,
[e-mail] writes:

...about the protests over proposals to put a giant billboard into orbit,

>I'd like to add that some of the "protests" do not come from a strictly
>practical consideration of what pollution levels are acceptable for research
>activities by professional astronomers.  Some of what I would complain about
>is rooted in aesthetics.

>Regards,
>Wm. Hathaway
>Baltimore MD

Mr. Hathaway's post is right on the money, if a little lengthy.  In short,
an orbiting billboard would be trash, in the same way that a billboard on
the Earth is trash.  Billboards make a place look trashy.  That is why there
are laws in many places prohibiting their use.  The light pollution
complaints are mainly an attempt to find some tangible reason to be against
orbiting billboards because people don't feel morally justified to complain
on the grounds that these things would defile the beauty of the sky.

Regular orbiting spacecraft are not the same in this respect, since they are
more like abstract entities, but a billboard in space would be like a beer
can somebody had thrown on the side of the road: just trash.

_____________
Dale M. Greer, whose opinions are not to be confused with those of
  The Center for Space Sciences, University of Texas at Dallas
   UTSPAN::UTADNX::UTDSSA::GREER or [e-mail]
"Let machines multiply, doing the work of many,
               But let the people have no use for them." - Lao Tzu

------------------------------

End of Space Digest Volume 16 : Issue 494
------------------------------