Earth Flyby: January 15, 2001
1100 Days Since Earth Flyby
Stardust Earth Gravity Assist (EGA)
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 The Stardust spacecraft during its
Earth flyby will be within 3700 miles
or 6000 kilometers above Earth. |
Stardust Performs Earth Gravity Assist
Earth closest approach for Stardust occurred on Monday, January 15, 2001, at 11:14.28 UTC (4:14.28 am MST, 3:14.28 am PST). The Stardust spacecraft started the Earth Gravity Assist (EGA) phase of its mission on Tuesday, November 28, 2000, 48 days from closest approach to Earth. On November 28, the spacecraft executed the first of three flight path corrections planned for the EGA phase. The primary objective of the EGA is to provide Stardust with an energy boost from flying past the Earth. The boost, which comes from sling-shoting around the Earth, i.e. a "gravity assist", will increase the spacecraft's orbital period around the Sun from 2 years to 2-1/2 years and alter its flight path to intercept Comet P/Wild-2 on January 2, 2004.
Spacecraft activities are fairly quiescent on approach to Earth, with only engineering housekeeping on the agenda. An attitude maintenance turn was performed on Tuesday, December 5, 2000 to keep the spacecraft's forward-looking medium gain antenna pointed toward the Earth while maintaining adequate sunlight on the spacecraft's power-generating solar arrays. STARDUST successfully completed Trajectory Correction Maneuver #5 (TCM-5) on January 5, 2001, the final targeting for Earth flyby. Five Navigation Camera images were taken to assess camera performance after the 2nd heating sequence where both the CCD and mirror motor heaters were turned on for about 1 month. The spacecraft will then be left alone until after Earth flyby.
Computer animations of the Earth Flyby by Stardust are available here.
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Earth closest approach will occur on Monday, January 15, 2001, at approximately 11:20 UTC (4:20 am MST, 3:20 am PST). The spacecraft flies over a point just South-East of the southern tip of Africa, at a distance just over 6,000 kilometers (3,700 miles) from the surface, and a speed of approximately 10 kilometers per second (36,000 kilometers per hour, or 22,400 miles per hour).
Once past Earth, the spacecraft will transfer communications from its medium gain antenna to its aft-looking low gain antennas. Approximately 15 hours after closest approach to Earth, the spacecraft will fly within 98,000 kilometers (61,000 miles) of the Moon.
Will Stardust be visible from Earth during the flyby? Perhaps.
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Approximately 20 days after closest approach, the spacecraft performs another attitude maintenance turn. The turn also allows Stardust to transfer all communications from its low gain antennas back to the medium gain antenna. The EGA phase comes to a close on Wednesday, February 14, 2001, when the spacecraft performs the last of the EGA flight path corrections. This final maneuver will correct errors incurred in the spacecraft's flight path since its maneuver on December 5, 2000.
Last Updated: November 26, 2003
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