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- . RCA ASTRO RECEIVES CONTRACT FOR MARS OBSERVER
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- . The Jet Propulsion Laboratory has selected the Astro-Electronics
- Division of RCA, located in Princeton, New Jersey as spacecraft contractor
- for the Mars Observer mission. This is the first of the Planetary Observers,
- a series of low cost missions for the exploration of the inner solar system.
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- . In order to achieve the requisite economies, a new procurement
- philosophy is being utilized. Rather than "reinvent the wheel" by designing
- a new vehicle from scratch for each mission, JPL's approach emphasizes use
- of existing, production line spacecraft designs and technology, particularly
- platforms originally designed as Earth-orbiting communication or weather
- satellites. These will be refitted for the contemplated mission by the
- addition of scientific instruments, chosen to fit within the constraints of
- the existing spacecraft design, and whatever engineering modifications may be
- appropriate to transform an Earth-orbital satellite into a spacecraft capable
- of traveling to and conducting experiments at other bodies in the inner solar
- system. In the case of the Mars Observer, the spacecraft selected after a
- competitive procurement process will be based on RCA Astro's SATCOM
- communications satellite. The electronic subsystems will use proven designs
- from the TIROS and DMSP series of meterological satellites.
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- . Present plans call for the spacecraft to be launched on an August 1990
- Space Shuttle mission. An upper stage will then be used to inject it into an
- interplanetary transfer orbit. The upper stage which has been selected for
- the mission is the Transfer Orbit Stage (TOS) which has been developed by
- Orbital Sciences Corporation of Vienna, Virginia as a privately financed
- venture. After approximately a one year transit flight, the spacecraft will
- arrive in the Martian vicinity and go into orbit around the planet. The
- initial orbit will be adjusted into a nearly circular, sun-synchronous, low
- altitude polar orbit. The probe's mission is to last for one Martian year,
- slightly less than two Earth years. Scientific objectives are modest and
- well defined. The principal purpose of the Mars Observer mission is to flesh
- out knowledge gained by the Mariner and Viking missions of the 1960's and
- 70's. The spacecraft will gather geoscience date by repetitive mapping of
- the Martian surface and climatological data by observation of the seasonal
- variation of the planet's atmosphere. It is hoped that this will resolve
- still unanswered questions about the Martian surface and atmosphere and how
- they interact.
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- . Mission operations for the Mars Observer as well as future planetary
- observer missions will be conducted from a new multimission operations
- facility at JPL called the Space Flight Operations Center.
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- . AN EXCURSION INTO HISTORY
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- . The Mars Observer program is in way a reminder of just how far we've
- come in a relatively short period of time. Mars makes its closest approach
- to the Earth, about thirty-five million miles, once every seventeen years.
- (The last such event occurred in 1971, and the next will be two years from
- now in 1988.) These used to be eagerly anticipated by astronomers who, on
- each such occasion hoped to unravel some of the mysteries of the Red Planet.
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- . The excitement began in the Nineteenth Century when the Italian
- astronomer Giovanni Schiaparelli reported he had observed some dark lines on
- the Martian surface which he called "canali." In Italian this simply means
- "channels." However, the coincidence with the English word "canal"
- immediately fueled speculation that Mars supported not only intelligent life
- but an advanced civilization capable of undertaking a planet-wide engineering
- project, the construction of a vast irrigation system to bring water from the
- planets polar caps to its arid desert regions. (Today it is theorized that
- what Schiaparelli actually saw may have been chains of craters on the Martian
- surface. In his relatively small telescope these appeared to be linked
- together to form a continuous line.)
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- . The possibility that Mars might be inhabited inspired, among other
- things, H. G. Well's classic story The War of the Worlds, which depicted a
- Martian invasion of the Earth. When produced as a radio program by Orson
- Wells in 1938, this created panic among listeners who thought they had tuned
- into a newscast instead of a drama. On a more serious scientific level, some
- reports say that during Mars 1937 approach the Navy ordered its ships to
- confine their radio traffic to essential messages so as to enhance the
- likelihood of picking up possible Martian transmissions. Not to be outdone,
- the Army had team of cryptoanalysts headed by William Friedman (who on the
- eve of the Second World War would break the Japanese PURPLE code) standing by
- to decipher any messages received.
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- . The 1954 event was likewise eagerly awaited. This would be the first
- occasion on which Mars could be observed through the 200 inch Mount Palomar
- telescope. It was hoped that this instrument could not only confirm the
- existence of the "canali" but determine if they followed great circle
- tracks, which would be evidence of artificial construction. One writer
- looked beyond 1954 to the 1971 apparition and stated that it was not too
- much to expect that there might be a telescope outside the Earth's
- atmosphere by that point, although even he did not venture to predict that
- by then spacecraft from Earth would have flown by the planet.