Illustration of the Dawn spacecraft
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Mission type | Multi-target orbiter | ||||||||
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Operator | NASA / JPL | ||||||||
COSPAR ID | 2007-043A | ||||||||
SATCAT № | 32249 | ||||||||
Website | http://dawn.jpl.nasa.gov/ | ||||||||
Mission duration | Planned: 9 years Elapsed: 9 years, 3 months, 27 days |
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Spacecraft properties | |||||||||
Manufacturer | Orbital Sciences · JPL · UCLA | ||||||||
Launch mass | 1,217.7 kg (2,684.6 lb) | ||||||||
Dry mass | 747.1 kg (1,647.1 lb) | ||||||||
Dimensions | 1.64 × 19.7 × 1.77 m (5.4 × 65 × 5.8 ft) | ||||||||
Power | 10,000 watts at 1 AU 1,300 watts at 3 AU |
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Start of mission | |||||||||
Launch date | September 27, 2007, 11:34 | UTC||||||||
Rocket | Delta II 7925H | ||||||||
Launch site | Cape Canaveral SLC-17B | ||||||||
Contractor | United Launch Alliance | ||||||||
Flyby of Mars | |||||||||
Closest approach | February 18, 2009, 00:27:58 UTC | ||||||||
Distance | 542 km (337 mi) | ||||||||
4 Vesta orbiter | |||||||||
Orbital insertion | July 16, 2011, 04:47 UTC | ||||||||
Departed orbit | September 5, 2012, 06:26 UTC | ||||||||
1 Ceres orbiter | |||||||||
Orbital insertion | March 6, 2015, 12:29 UTC | ||||||||
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Instruments | |
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FC | Framing Camera |
VIR | Visible and Infrared Spectrometer |
GRaND | Gamma Ray and Neutron Detector |
Dawn mission patch
Dawn is a space probe launched by NASA in September 2007 with the mission of studying two of the three known protoplanets of the asteroid belt, Vesta and Ceres. It is currently in orbit about its second target, the dwarf planet Ceres. Dawn is the first spacecraft to orbit two extraterrestrial bodies, the first spacecraft to visit either Vesta or Ceres, and also the first to visit a dwarf planet, arriving at Ceres in March 2015, a few months before New Horizons flew by Pluto in July 2015.
Dawn entered Vesta orbit on July 16, 2011, and completed a 14-month survey mission before leaving for Ceres in late 2012.Dawn entered Ceres orbit on March 6, 2015, and is predicted to remain in orbit perpetually after the conclusion of its mission. NASA considered, but decided against, a proposal to visit a third target.
The Dawn mission is managed by NASA's Jet Propulsion Laboratory, with spacecraft components contributed by European partners from the Netherlands, Italy and Germany. It is the first NASA exploratory mission to use ion propulsion, which enabled it to enter and leave the orbit of multiple celestial bodies. Previous multi-target missions using conventional drives, such as the Voyager program, were restricted to flybys.
The first working ion thruster was built by Harold R. Kaufman in 1959 at NASA's Glenn Research Center in Ohio. The thruster was similar to the general design of a gridded electrostatic ion thruster with mercury as its propellant. Suborbital tests of the engine followed during the 1960s, and in 1964 the engine was tested on a suborbital flight aboard the Space Electric Rocket Test 1 (SERT 1). It successfully operated for the planned 31 minutes before falling back to Earth. This test was followed by an orbital test, SERT-2, in 1970.