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Two Upper-Atmosphere Research Satellites, UARS-1 and UARS-2, will be launched as part of the Upper Atmosphere Research Program. The basic objectives of the UARS-2 mission are to conduct research in the atmosphere above the tropopause, and to measure the global budget of constituent trace gases and their chemical, dynamical, and radiative behavior. Specifically, the objectives are (1) to study energy input and loss in the upper atmosphere; (2) to study global atmospheric photochemistry; (3) to study upper-atmosphere dynamics; and (4) to study the coupling among processes and between atmospheric regions. UARS-2 will be launched 1 year after UARS-1 into a similar 600-km circular orbit, but with a higher inclination angle. The planned lifetime for each spacecraft is 18 months, but this may be extended by retrieval or in-orbit refurbishment/resupply by the Shuttle. The UARS has two major components. The first is the multimission modular spacecraft (MMS), designed as a standard bus for the NASA spacecraft missions (e.g., SMM and LANDSAT-D), and consisting of four basic modules: attitude control subsystem; power subsystem; communications and data handling sybsystem; and propulsion module. The second major component is an instrument assembly (IA) which is composed of the following instrument modules: (1) the four microwave antennas and their momentum-compensating devices; (2) a solar-pointed instrument platform with solar instruments; (3) the cryogenic limb interferometer instrument; (4) a module comprised of smaller instruments that do not require cryogenic cooling; and (5) a module comprised of smaller instruments that do contain cryogens. The MMS maintains a precise orientation to the local vertical and to the velocity vector. There are three on-board tape recorders. Three NASA standard 50-amp-h nickel-cadmium batteries are flown along with the solar-cell array. The data are returned to earth by TDRSS. A central data-processing facility with remote processing and display terminals at the investigators' institution was planned. This mission was cancelled.

Alternate Names

    Facts in Brief

    Launch Date: 1989-10-01
    Launch Vehicle: Shuttle
    Launch Site: Vandenberg AFB, United States
    Mass: 3225 kg

    Funding Agency

    • NASA-Office of Applications (United States)


    • Space Physics
    • Solar Physics
    • Earth Science

    Additional Information

    Questions and comments about this spacecraft can be directed to: Coordinated Request and User Support Office



    NameRoleOriginal AffiliationE-mail
    Mr. Douglas R. BroomeProgram ManagerNASA Headquarters
    Mr. Peter T. BurrProject ManagerNASA Goddard Space Flight Center
    Dr. Robert J. McNealProgram ScientistNASA Headquarters
    Dr. Nelson W. SpencerProject ScientistNASA Goddard Space Flight Center
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