NASA scientists have strung together images of comet
Borrelly to produce short movies of the comet as it travels
through space.

In one clip, the bare, rocky, icy nucleus wobbles back
and forth to reveal its textured surface, with some smooth and
some bumpy landscapes. The observations were taken when NASA’s
Deep Space 1 spacecraft was between 3,700 and 9,500 kilometers
(between 2,300 and 5,900 miles) from the comet in September

In the second clip, jets of gas and dust shoot from all
sides of the comet’s nucleus as it rotates a quarter turn. The
biggest jet, shooting from the central sunlit part of the
comet, is probably in line with the axis around which the
nucleus rotates. This large jet is eroding the central part
of the comet, smoothing parts of the terrain into rolling
hills. The erosion will eventually break the comet into
pieces. Coarsely textured parts of the comet at both ends are
geologically inactive areas. These images were taken from
between 22,500 and 4,980 kilometers (about 14,000 to 3,000
miles) away.

The images are available online from NASA’s Jet
Propulsion Laboratory, Pasadena, Calif., at .

NASA TV will broadcast a video file of the comet movies
at 12, 3, 6 and 9 p.m. EST Thursday, Nov. 29. NASA TV is
located on satellite GE2, Transponder 9C, audio 3880 MHz;
orbital position 85 degrees west longitude, with audio at 6.8

Scientists are studying these images and other Deep Space
1 data for a better understanding of comets and their role in
the solar system. Deep Space 1’s pass through comet Borrelly’s
surrounding cloud of gas and dust yielded the best pictures
ever of a comet’s rocky, icy nucleus. The images appear to
show the comet rotating but it is actually the spacecraft that
changed position as it passed close to the comet’s nucleus.

Deep Space 1 completed its primary mission testing ion
propulsion and 11 other advanced, high-risk technologies in
September 1999. NASA extended the mission, taking advantage of
the ion propulsion and other systems to undertake this chancy
but exciting, and ultimately successful encounter. More
information is available on the home page at .

Deep Space 1 was launched in October 1998 as part of
NASA’s New Millennium Program, which is managed by JPL for
NASA’s Office of Space Science, Washington, D.C. The
California Institute of Technology manages JPL for NASA.