Magellan
Mission to Venus
The Magellan spacecraft was launched on May 4, 1989,
arrived at Venus on
August 10, 1990 and was inserted into a near-polar
elliptical orbit with a periapsis altitude of 294 km at
9.5 deg. N. Radio contact with Magellan was lost on
October 12, 1994. The primary objectives of the Magellan
mission were to map the surface of Venus with a synthetic
aperture radar (SAR) and to determine the topographic
relief of the planet. At the completion of radar mapping
98% of the surface was imaged at resolutions better than
100 m, and many areas were imaged multiple times. The
image at the top of the page shows the 30-km diametar
crater Adivar, with a jet-like streak extending off to
the left. The streak, which measures over 500 km in
length, is probably the result of the initial
crater-forming impact. (This image is from C1-MIDR
15N077;1, framelet 52, Magellan CD-ROM MG_0019.) The
mission was divided up into "cycles", each
cycle lasted 243 days (the time necessary for Venus to
rotate once under the Magellan orbit - i.e. the time
necessary for Magellan to "see" the entire
surface once.) The mission proceeded as follows:
04 May 1989 - Launch
10 Aug 1990 - Venus orbit insertion and spacecraft checkout
15 Sep 1990 - Cycle 1: Radar mapping (left-looking)
15 May 1991 - Cycle 2: Radar mapping (right-looking)
15 Jan 1992 - Cycle 3: Radar mapping (left-looking)
14 Sep 1992 - Cycle 4: Gravity data acquisition
24 May 1993 - Aerobraking to circular orbit
03 Aug 1993 - Cycle 5: Gravity data acquisition
30 Aug 1994 - Windmill experiment
12 Oct 1994 - Loss of radio signal
13 Oct 1994 - Expected loss of spacecraft
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