Date: 1 Feb 1995 20:22:34 -0500
From: leech@cs.unc.edu (Jon Leech)
Newsgroups: sci.space.tech,sci.space.science,sci.answers,news.answers
Subject: Space FAQ 09/13 - Upcoming Planetary Probes

Archive-name: space/new_probes
Last-modified: $Date: 95/02/01 20:19:24 $

    Compilation copyright (c) 1994 by Jonathan P. Leech. This document may
    be redistributed in its complete and unmodified form. Other use requires
    written permission of the author.

UPCOMING PLANETARY PROBES - MISSIONS AND SCHEDULES

    Information on upcoming or currently active missions not mentioned below
    would be welcome. Sources: NASA fact sheets, Cassini Mission Design
    team, ISAS/NASDA launch schedules, press kits.


    ASCA (ASTRO-D) - Japanese (ISAS) Advanced Satellite for Cosmology and
    Astrophysics. ASCA is an X-ray astronomy satellite launched into Earth
    orbit on 2/20/93. Equipped with large-area wide-wavelength (1-20
    Angstrom) X-ray telescope, X-ray CCD cameras, and imaging gas
    scintillation proportional counters.


    CASSINI - Saturn orbiter and Titan atmosphere probe. Cassini is a joint
    NASA/ESA project designed to accomplish an exploration of the Saturnian
    system with its Cassini Saturn Orbiter and Huygens Titan Probe. Cassini
    is scheduled for launch aboard a Titan IV/Centaur in October of 1997.
    After gravity assists of Venus, Earth and Jupiter in a VVEJGA
    trajectory, the spacecraft will arrive at Saturn in June of 2004. Upon
    arrival, the Cassini spacecraft performs several maneuvers to achieve an
    orbit around Saturn. Near the end of this initial orbit, the Huygens
    Probe separates from the Orbiter and descends through the atmosphere of
    Titan. The Orbiter relays the Probe data to Earth for about 3 hours
    while the Probe enters and traverses the cloudy atmosphere to the
    surface. After the completion of the Probe mission, the Orbiter
    continues touring the Saturnian system for three and a half years. Titan
    synchronous orbit trajectories will allow about 35 flybys of Titan and
    targeted flybys of Iapetus, Dione and Enceladus. The objectives of the
    mission are threefold: conduct detailed studies of Saturn's atmosphere,
    rings and magnetosphere; conduct close-up studies of Saturn's
    satellites, and characterize Titan's atmosphere and surface.

    One of the most intriguing aspects of Titan is the possibility that its
    surface may be covered in part with lakes of liquid hydrocarbons that
    result from photochemical processes in its upper atmosphere. These
    hydrocarbons condense to form a global smog layer and eventually rain
    down onto the surface. The Cassini orbiter will use onboard radar to
    peer through Titan's clouds and determine if there is liquid on the
    surface. Experiments aboard both the orbiter and the entry probe will
    investigate the chemical processes that produce this unique atmosphere.

    The Cassini mission is named for Jean Dominique Cassini (1625-1712), the
    first director of the Paris Observatory, who discovered several of
    Saturn's satellites and the major division in its rings. The Titan
    atmospheric entry probe is named for the Dutch physicist Christiaan
    Huygens (1629-1695), who discovered Titan and first described the true
    nature of Saturn's rings.

         Key Scheduled Dates for the Cassini Mission (VVEJGA Trajectory)
         -------------------------------------------------------------
           10/06/97 - Titan IV/Centaur Launch
           04/21/98 - Venus 1 Gravity Assist
           06/20/99 - Venus 2 Gravity Assist
           08/16/99 - Earth Gravity Assist
           12/30/00 - Jupiter Gravity Assist
           06/25/04 - Saturn Arrival
           01/09/05 - Titan Probe Release
           01/30/05 - Titan Probe Entry
           06/25/08 - End of Primary Mission
            (Schedule last updated 7/22/92)


    CLEMENTINE - Joint mission of the Ballistic Missile Defense Organization
    (formerly SDIO) and NASA to flight test sensors developed by Lawrence
    Livermore for BMDO. The spacecraft, built by the Naval Research Lab, was
    launched on January 25 to a 425 km by 2950 km orbit of the Moon for a 2
    month mapping mission. Instruments onboard include UV to mid-IR imagers,
    including an imaging lidar that may be able to also obtain altimetric
    data for the middle latitudes of the Moon. In early May the spacecraft
    was sent out of Lunar orbit towards a flyby of the asteroid Geographos,
    but a malfunction in the onboard computer system resulted in loss of the
    spacecraft.

    Clementine imagery and other data may be obtained from

        ftp://clementine.s1.gov/pub/clementine/images
        ftp://seds.lpl.arizona.edu/pub/spacecraft/CLEMENTINE


    EARTH OBSERVING SYSTEM (EOS) - Multiple orbiting platforms to provide
    long-term data of Earth systems science including planetary evolution.
    Platform launches are scheduled throughout the late 1990s.

    Lots of information about EOS can be found in the sci.geo.eos FAQ or

        http://spso2.gsfc.nasa.gov/spso_homepage.html


    GALILEO - Jupiter orbiter and atmosphere probe, in transit. Has returned
    the first resolved images of asteroids, Gaspra and Ida, while in transit
    to Jupiter. Efforts to unfurl the stuck High Gain Antenna (HGA) have
    essentially been abandoned. JPL has developed a backup plan using
    enhancements of the receiving antennas in the Deep Space Network and
    data compression (JPEG-like for images, lossless compression for data
    from the other instruments) on the spacecraft. This should allow Galileo
    to achieve approximately 70% of its original science objectives with the
    much lower speed Low Gain Antenna. Longterm Jovian weather monitoring,
    which is imagery intensive, will suffer the most.

           Galileo Schedule
           ----------------
           10/18/89 - Launch from Space Shuttle
           02/09/90 - Venus Flyby
           10/**/90 - Venus Data Playback
           12/08/90 - 1st Earth Flyby
           05/01/91 - High Gain Antenna (was to have) Unfurled
           07/91 - 06/92 - 1st Asteroid Belt Passage
           10/29/91 - Asteroid Gaspra Flyby
           12/08/92 - 2nd Earth Flyby
           05/93 - 11/93 - 2nd Asteroid Belt Passage
           08/28/93 - Asteroid Ida Flyby
           07/13/95 - Probe Separation
           07/20/95 - Orbiter Deflection Maneuver
           12/95 - 10/97 - Orbital Tour of Jovian Moons
           12/07/95 - Jupiter/Io Encounter
           07/04/96 - Ganymede-1
           09/06/96 - Ganymede-2
           11/04/96 - Callisto-3
           12/19/96 - Europa-4
           01/20/97 - Europa-5A
           02/20/97 - Europa-6
           04/05/97 - Ganymede-7
           05/07/97 - Ganymede-8
           06/25/97 - Callisto-9
           09/17/97 - Callisto-10
           11/06/97 - Europa-11


    HITEN (MUSES-A) - Japanese (ISAS) lunar probe launched 1/24/90. Made
    multiple lunar flybys and released Hagoromo, a smaller satellite, into
    lunar orbit. This mission made Japan the third nation to orbit a
    satellite around the Moon. Hiten impacted the lunar surface on 4/10/93.


    MAGELLAN - Venus radar mapping mission. Mapped almost the entire surface
    at high resolution and compiled a global gravity map. Magellan ended its
    extended mission in October 12, 1994 during an aerobraking experiment
    which (intentionally) caused entry into the Venusian atmosphere. For more
    info, see

        http://newproducts.jpl.nasa.gov/magellan/


    MARS GLOBAL SURVEYOR - A replacement mission to achieve most of the
    goals of the failed Mars Observer mission, to be launched by a Delta 2
    booster in November 1996. For more info, see

        http://www.jpl.nasa.gov/mgs.html


    MARS OBSERVER - Mars orbiter including 1.5 m/pixel resolution camera.
    Launched 9/25/92 on a Titan III/TOS booster. Contact was lost with MO on
    8/21/93 while it was preparing for entry into Mars orbit. The spacecraft
    has been written off.


    TOPEX/Poseidon - Joint US/French Earth observing satellite, launched
    8/10/92 on an Ariane 4 booster. The primary objective of the
    TOPEX/POSEIDON project is to make precise and accurate global
    observations of the sea level for several years, substantially
    increasing understanding of global ocean dynamics. The satellite also
    will increase understanding of how heat is transported in the ocean.


    ULYSSES- European Space Agency probe to study the Sun from an orbit over
    its poles. Launched in late 1990, it carries particles-and-fields
    experiments (such as magnetometer, ion and electron collectors for
    various energy ranges, plasma wave radio receivers, etc.) but no camera.

    Since no human-built rocket is hefty enough to send Ulysses far out of
    the ecliptic plane, it went to Jupiter instead, and stole energy from
    that planet by sliding over Jupiter's north pole in a gravity-assist
    manuver in February 1992. This bent its path into a solar orbit tilted
    about 85 degrees to the ecliptic. It will pass over the Sun's south pole
    in the summer of 1994. Its aphelion is 5.2 AU, and, surprisingly, its
    perihelion is about 1.5 AU-- that's right, a solar-studies spacecraft
    that's always further from the Sun than the Earth is!

    While in Jupiter's neigborhood, Ulysses studied the magnetic and
    radiation environment. For a short summary of these results, see
    *Science*, V. 257, p. 1487-1489 (11 September 1992). For gory technical
    detail, see the many articles in the same issue.


    OTHER SPACE SCIENCE MISSIONS (various sources; corrections and updates
    are solicited. Launch dates are usually tentative, and most shuttle
    missions are not listed even when they have some science content).

    1995
        o SL-M (Spacelab - MIR) [May, Shuttle, MIR]
            Space Shuttle docking with Russian MIR station. Life sciences
            mission (Spacelab).

        o MUSES-B (Mu Space Engineering Satellite-B) [ISAS]
            Conducting research on the precise mechanism of space structure
            and in-space astronomical observations of electromagnetic waves.

    1996
        o ADEOS [NASDA]
            Advanced Earth Observing Satellite.

        o PLANET-B [ISAS]
            Mars orbiter to study the structure and motions of the Martian
            atmosphere and its interaction with the solar winds.

        o NEAR [February, Delta 2, NASA]
            Discovery-class mission to rendezvous with near-Earth asteroid
            Eros in 1998. NEAR will orbit Eros for at least one year to
            conduct the first comprehensive measurements of an asteroid's
            mass, structure, geology, mineral composition, and gravity and
            magnetic fields.

        o VSOP (VLBI Space Observatory Program) [NASDA]
            Scheduled to be launched ~8/96. NASA is building 3 specialized
            tracking stations to record the wideband radioastronomy data
            that this spacecraft will produce.

    1997
        o ISELA [International Space Enterprises/Lavochkin Association]
            Commercial proposal to land a rover on the Moon in the vicinity
            of the Apollo 11 site, followed by 3-6 months of exploration.
            Contact Tom Kessler (tomkessler@aol.com) of ISE for details.

        o LUNAR-A [ISAS]
            Elucidating the crust structure and thermal construction of the
            moon's interior.

        o MARS PATHFINDER [Delta 2, NASA]
            Lander and microrover to perform technology, science and
            engineering experiments on the Martian Surface. See

                http://mpfwww.jpl.nasa.gov/~jwright/fact_sheet/fact_sheet.html

        o RADIOASTRON [Russian space agency]
            Same purpose as 1996 VSOP mission. NRAO is building similar
            ground stations for tracking. These two spacecraft will
            coobserve radio sources in conjunction with ground based VLBA
            radio telescopes.

    2003
        o ROSETTA [ESA]
            Asteroid flyby and comet rendezvous (potential target comets are
            Schwassmann-Wachmann 3, Wirtanen, Finlay and Brooks 2 for a
            launch in the time interval 2002-2004). After rendezvous,
            the spacecraft will stay with the comet along its trajectory
            into the inner solar system through perihelion (the orbital
            point nearest to the Sun) to study the material that constitutes
            the comet, and the cometary processes that evolve with the
            decreasing distance from the Sun. A Surface Science Station will
            be deployed onto the comets' nucleus surface to provide the
            means for in-situ studies of the nucleus.

    2006
        o FIRST (Far InfraRed Space Telescope) [ESA]
            Large (3-meter mirror) space observatory.

    Proposed Missions:
        o Advanced X-ray Astronomy Facility (AXAF)
            Possible launch from shuttle in 1995, AXAF is a space
            observatory with a high resolution telescope. It would orbit for
            15 years and study the mysteries and fate of the universe.

        o Clementine II
            Preliminary studies for a Clementine II mission have been done
            by JPL, APL, and NRL, envisioning multiple asteroid or
            asteroid/comet encounters. No funding has been allocated for
            such missions.

        o Pluto Fast Flyby (PFF)
            Possible launch in 1999-2000 (if a 1996 new start is
            authorized). Calls for launch of two ~110-150 kg spacecraft
            using Titan IV/Centaur or Proton (both with additional solid
            kick stages) in 1999-2000 and encounters with Pluto and Charon
            around 2006-8. Flybys would be at 12-18 km/second; data would be
            recorded onboard the probes during the short encounters and
            returned to Earth slowly (due to low power, small antenna sizes,
            and large distances) over the next year or so.

            Science objectives include characterizing global geology and
            geomorphology of Pluto and Charon, mapping both sides of each
            body, and characterizing Pluto's atmosphere (the atmosphere is
            freezing out as Pluto moves away from the Sun, so launching
            early and minimizing flight time is critical for this
            objective). The 7 kilogram instrument package might include a
            CCD imaging camera, IR mapping spectrometer, UV spectrometer,
            and radio science occultation experiments.

            The PFF spacecraft would be highly miniaturized descendant of
            the present class of outer solar system platforms, breaking the
            trend of increasingly complex and expensive probes such as
            Galileo and Cassini.

        o Space Infrared Telescope Facility
            Possible launch by shuttle in 1999, this is the 4th element of
            the Great Observatories program. A free-flying observatory with
            a lifetime of 5 to 10 years, it would observe new comets and
            other primitive bodies in the outer solar system, study cosmic
            birth formation of galaxies, stars and planets and distant
            infrared-emitting galaxies

NEXT: FAQ #10/13 - Controversial questions
