Explanation:
The Deep Impact spacecraft continues to close on
Comet Tempel 1, a comet roughly the size of Manhattan.
Early on July 3 (EDT), the
Deep Impact spacecraft will separate in to two individual
robotic spaceships, one called Flyby and the other called Impactor.
During the next 24 hours, both Flyby and Impactor will
fire rockets and undergo complex maneuvers in preparation for Impactor's
planned collision with
Comet Tempel 1.
On July 4 (1:52 am EDT) if everything goes as scheduled,
the 370-kilogram Impactor will strike
Tempel 1's surface at over 14,000 kilometers per hour.
Impactor will attempt to photograph the oncoming comet right up
to the time of collision, while Flyby photographs the result from nearby.
The above image was taken on 19 June from about 13 million kilometers
out and used to help
identify the central nucleus of the comet inside the diffuse
coma.
Telescopes around the
Earth, including the Hubble Space Telescope,
will also be closely watching the distant silent
space ballet.
The result may give crucial information about the
structure of comets
and the early
history of our Solar System.