![]() ![]() ![]() Russell was chosen to lead the Dawn mission team. Although originally projected to cost US$373 million, cost overruns inflated the final cost of the mission to US$446 million in 2007. In the last week of September 2006, the Dawn mission's instrument payload integration reached full functionality. NASA then put the cancellation under review, and on March 27, 2006, it was announced that the mission would not be cancelled after all. The spacecraft's manufacturer, Orbital Sciences Corporation, appealed NASA's decision, offering to build the spacecraft at cost, forgoing any profit in order to gain experience in a new market field. On March 2, 2006, Dawn was again cancelled by NASA. In October 2005, work on Dawn was placed in "stand down" mode, and in January 2006, the mission was discussed in the press as "indefinitely postponed", even though NASA had made no new announcements regarding its status. The project was cancelled in December 2003, and then reinstated in February 2004. The status of the Dawn mission changed several times. Both missions were initially selected for a launch in 2006. In December 2001 NASA selected the Kepler and the Dawn mission for the Discovery program. Three semi-finalists were downselected in January 2001 for a phase-A design study: Dawn, Kepler, and INSIDE Jupiter. Twenty-six proposals were submitted to the Discovery Program solicitation, with budget initially targeted at US$300 million. In addition to the ion thruster, among the other technologies validated by the DS1 was the Small Deep Space Transponder, which is used on Dawn for long-range communication. This test was followed by an orbital test, SERT-2, in 1970.ĭeep Space 1 (DS1), which NASA launched in 1998, demonstrated the long-duration use of a xenon-propelled ion thruster on a science mission, and validated a number of technologies, including the NSTAR electrostatic ion thruster, as well as performing a flyby of an asteroid and a comet. It successfully operated for the planned 31 minutes before falling back to Earth. 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). The thruster was similar to the general design of a gridded electrostatic ion thruster with mercury as its propellant. Kaufman in 1959 at NASA's Glenn Research Center in Ohio. The first working ion thruster in the US was built by Harold R. Project history Technological background SERT-1: first ion engine NASA spacecraft launched on July 20, 1964. Previous multi-target missions using rockets powered by chemical engine, such as the Voyager program, were restricted to flybys. It was the first NASA exploratory mission to use ion propulsion, which enabled it to enter and leave the orbit of two celestial bodies. The Dawn mission was managed by NASA's Jet Propulsion Laboratory, with spacecraft components contributed by European partners from Italy, Germany, France, and the Netherlands. ĭawn is the first spacecraft to have orbited two extraterrestrial bodies, the first spacecraft to have visited either Vesta or Ceres, and the first to have orbited a dwarf planet. The derelict probe remains in a stable orbit around Ceres. On November 1, 2018, NASA announced that Dawn had depleted its hydrazine, and the mission was ended. ![]() In 2017, NASA announced that the planned nine-year mission would be extended until the probe's hydrazine fuel supply was depleted. It entered orbit around Ceres on March 6, 2015. In the fulfillment of that mission-the ninth in NASA's Discovery Program- Dawn entered orbit around Vesta on July 16, 2011, and completed a 14-month survey mission before leaving for Ceres in late 2012. September 27, 2007, 11:34 ( UTC11:34) UTC Ģ,475.1356 kilometres (1,537.9780 mi) ĭawn is a retired space probe that was launched by NASA in September 2007 with the mission of studying two of the three known protoplanets of the asteroid belt: Vesta and Ceres. ![]()
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