The spacecraft Deep Space 1 was launched October 24, 1998 on top of a Delta rocket. As part of NASA's New Millennium program, the primary goal was the testing of twelve advanced technologies that have the potential to lower the cost and risk of future missions.

Among the technologies tested were:

• an ion thruster, specifically a NSTAR electrostatic ion thruster
• 'autonav' (an autonomous navigation system)
• 'Remote agent' (remote intelligent self-repair software)

Deep Space 1 succeeded in its tasks and also achieved its secondary goals: flybys of the asteroid Braille and of Comet Borrelly, returning valuable science data and stunning pictures. Deep Space 1 was retired on December 18, 2001.

Achievements

The ion propulsion engine initially failed after 4 hours of operation. However, it was later restored to action and performed excellently.

The Autonav system required a couple of manual corrections, mostly for problems with identifying objects that were not bright enough or were difficult to identify because of the interference of light.

The flyby of Braille was only a partial success. Deep Space 1 was intended to perform the flyby at 56,000 km/h at only 240 meters from the asteroid. Due to technical difficulties, including a software crash on approach, the craft instead passed Braille at a distance of 26 km. This meant that the asteroid was not bright enough for the autonav to focus the camera in the right direction, and the picture shoot was delayed by almost an hour. The resulting pictures were disappointingly indistinct.

However, the flyby of Comet Borrelly was a great success and returned extremely detailed images of the comet's surface.

Statistics

• the mass of the craft: 486.32 kg (including fuel)
• total cost: $149.7 million
• development cost: $94.8 million
• launch site: Cape Canaveral Air Station, Florida
• maximum power: 2500W (of which 2100W powers the ion thrust engine)
• project manager: Dr. Marc Rayman

See also: Unmanned space missions

External links

• The Encyclopedia Astronautica
• Deep Space 1 website at the Jet Propulsion Laboratory (JPL)