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The Planetary Society Blog
By Emily Lakdawalla
Dawn has been reinstated!
Mar. 27, 2006 | 11:28 PST | 19:28 UTC
NASA just issued a press release (copied below), and conducted a very hastily assembled press teleconference to announce that the Dawn mission to the asteroids Ceres and Vesta, which was canceled abruptly on March 2, has been reinstated. I called in to the teleconference and listened for the first few minutes as a veritable waterfall of other people joined the teleconference, from every major mainstream and space news outlet -- there is clearly a lot of public interest in this mission, or at least in the process by which it was first canceled and then reinstated. We will probably have an in-depth story on our website in the next day or so, so I'll just mention a few highlights.
The two panelists were NASA Associate Administrator Rex Geveden, who chaired the review panel, and Deputy Administrator for Space Science Colleen Hartman. Geveden began by saying that the xenon tank "qualification matter is now settled" and that "there is a way forward on...spacecraft structural concerns." Furthermore, the cost estimates are "improved" in that there is "reduced uncertainty" in the budget. Overall, during the conference, Geveden's tone indicated that while the review had been quite necessary, NASA is now confident in the Dawn mission's ability to move forward and launch in 2007. Later in the conference he said things like "I think Dawn as a project, as a mission, at this stage of its integration, has a typical sort of risk profile to it" and that "these missions are always pretty tall challenges, and it looks like Dawn is ready to take those on, and beat them."
Hartman, for her part, opened by emphasizing the quality of the science that Dawn would be doing, studying Ceres and Vesta; I think that by stating this clearly she wanted also to state that the NASA Science Mission Directorate has not lost sight of the fact that these missions are about important science. She said that Dawn has been hard because it is the "first science mission ever that uses ion propulsion." (Deep Space 1, which she mentioned, and ESA's SMART-1 and JAXA's Hayabusa, which she didn't, were all technology demonstration missions on which the science they did/are doing is a secondary goal.) However, when asked if Dawn's problems were due to problems scaling up the Deep Space 1 design, she said that "the mission itself has other issues as well."
The stand down, cancellation, and reinstatement have imposed a schedule delay. Originally planned to launch in 2006, it will now launch in the summer of 2007. Geveden said that the assessment team believes that an August launch date is quite likely. The project team at JPL believes they could be ready for launch in "the June-July time frame." He said that the two estimates were in "essential agreement," in that there are 2 to 3 months of schedule reserve in these estimates to accommodate any further challenges. Hartman said that the "arrival time actually hasn't changed" due to the launch delay, so we are still looking at a 2011 arrival at Vesta and a 2014 arrival at Ceres.
NASA REINSTATES THE DAWN MISSION
NASA senior management announced a decision Monday to reinstate the Dawn mission, a robotic exploration of two major asteroids. Dawn had been canceled because of technical problems and cost overruns.
The mission, named because it was designed to study objects dating from the dawn of the solar system, would travel to Vesta and Ceres, two of the largest asteroids orbiting the sun between Mars and Jupiter. Dawn will use an electric ion propulsion system and orbit multiple objects.
The mission originally was approved in December 2001 and was set for launch in June 2006. Technical problems and other difficulties delayed the projected launch date to July 2007 and pushed the cost from its original estimate of $373 million to $446 million. The decision to cancel Dawn was made March 2, 2006, after about $257 million already had been spent. An additional expenditure of about $14 million would have been required to terminate the project.
The reinstatement resulted from a review process that is part of new management procedures established by NASA Administrator Michael Griffin. The process is intended to help ensure open debate and thorough evaluation of major decisions regarding space exploration and agency operations.
"We revisited a number of technical and financial challenges and the work being done to address them," said NASA Associate Administrator Rex Geveden, who chaired the review panel. "Our review determined the project team has made substantive progress on many of this mission's technical issues, and, in the end, we have confidence the mission will succeed."
The Dawn decision document will be available on the Web at:
http://www.nasa.gov/formedia Here's that letter from Rex Geveden (PDF format).
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