Discover the cosmos! Each day a different image or photograph of
our fascinating universe is featured, along with a brief
explanation written by a professional astronomer. August 26,
1999 Explanation: Connect the dots and you'll trace the path of
the Cassini spacecraft as it took a final turn by Earth on its
way to the outer solar system. The dots (in a horizontal row
just below center) are actually successive images of the
spacecraft. The picture was produced by making exposures at 10
minute intervals as Cassini moved rapidly through Earth's night
sky on August 18 - around the time of its closest approach.
Cassini's ultimate destination is Saturn, but so far its voyage
has consisted of a series of fuel saving "gravity assist" flybys
of Venus and Earth, each designed to result in an increase in
the spacecraft's speed. During this Earth flyby Cassini received
about a 12,000 mile- per-hour (5.5 km/sec) boost. Cassini is now
being maneuvered toward yet another slingshot encounter, this
time a December 2000 flyby