On February 6, 1999 A Delta II rocket launched the Stardust spacecraft to rendezvous with Comet Wild-2 in January 2004.
STARDUST is a comet sample return mission which will also be returning interstellar dust grains. These samples will be returned to Earth for analysis. A mass spectrometer derived from instruments flown on Giotto and Vega Halley missions will also be included on the payload to provide both complementary and corroborative data to the sample return results. For the comet Wild 2 encounter, the objective is to recover more than one thousand particles larger than 15 microns in diameter as well as volatile molecules on the same capture medium. The sample return objective for fresh interstellar grains is to collect over 100 particles in the 0.1 micron to 1 micron size range. They will be collected in a manner designed to preserve, at minimum, the elemental and isotopic composition for major elements in individual submicron particles.
The STARDUST spacecraft will be launched in February 1999. The first orbital loop is a 2-year VEGA path with a 171 m/s delta-V trajectory correction maneuver (TCM) near aphelion. This delta-V will set up the Earth swingby that will pump the orbit up to the 2.5-year loop, which the spacecraft will fly twice.
At 160 days before encounter, a small delta-V of 66 m/s will set up the Wild 2 flyby. This will occur on 1 Jan 2004, at 1.86 AU and 97.5 days past Wild 2 perihelion passage.
The spacecraft will approach the comet at 6.2 km/s from sunside with a 70º phase angle. Coma fly-through will be on the sun side at a planned miss distance of 150 km. Flyby is five years after launch, and Earth return, two years later.
Copyright 1997 Dr. Sten Odenwald
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