Spacecraft on long interplanetary voyages [
http://www-spof.gsf…] often use the planets themselves as gravitational "sling shots" to boost them along their way. Launched [
http://stardust.jpl…commemorative.html ] in February of 1999 on a historic voyage to a comet, the Stardust spacecraft [
http://stardust.jpl…] is no different. On 15 January 2001 Stardust made its closest approach to planet Earth [
http://stardust.jpl…] since launch, coming within about 6,000 kilometers of the surface. It used this gravity assist maneuver [
http://www.jpl.nasa…] to increase its speed and alter its trajectory toward an encounter with comet Wild 2 [
http://www.ssep.org…], which it should reach in 2004. Shortly before its time of closest approach, astronomer Gordon Garradd recorded this exposure [
http://www.ozemail.…] of Stardust sailing through the skies above Loomberah, Australia. Nearby and moving fast [
http://stardust.jpl…], the spacecraft appears as a streak against a background of faint stars in the constellation Cetus [
http://www.astronom…]. Stardust cruised within just 98,000 kilometers of the Moon [
http://stardust.jpl…] about 15 hours later. After collecting [
http://stardust.jpl…aerogel.html ] dust from the tail of comet Wild 2, Stardust's voyage [
http://stardust.jpl…] will continue -- as it returns the samples to Earth in 2006.
Explanation
Spacecraft on long interplanetary voyages [
http://www-spof.gsf…] often use the planets themselves as gravitational "sling shots" to boost them along their way. Launched [
http://stardust.jpl…commemorative.html ] in February of 1999 on a historic voyage to a comet, the Stardust spacecraft [
http://stardust.jpl…] is no different. On 15 January 2001 Stardust made its closest approach to planet Earth [
http://stardust.jpl…] since launch, coming within about 6,000 kilometers of the surface. It used this gravity assist maneuver [
http://www.jpl.nasa…] to increase its speed and alter its trajectory toward an encounter with comet Wild 2 [
http://www.ssep.org…], which it should reach in 2004. Shortly before its time of closest approach, astronomer Gordon Garradd recorded this exposure [
http://www.ozemail.…] of Stardust sailing through the skies above Loomberah, Australia. Nearby and moving fast [
http://stardust.jpl…], the spacecraft appears as a streak against a background of faint stars in the constellation Cetus [
http://www.astronom…]. Stardust cruised within just 98,000 kilometers of the Moon [
http://stardust.jpl…] about 15 hours later. After collecting [
http://stardust.jpl…aerogel.html ] dust from the tail of comet Wild 2, Stardust's voyage [
http://stardust.jpl…] will continue -- as it returns the samples to Earth in 2006.
Explanation
