Report slams NASA's neglect of small missions

 作者:钟离酗完     |      日期:2018-02-25 07:01:02
By David Shiga NASA is facing a four-year-long “launch desert” of no new astronomy missions because of skewed priorities, a new report by an expert panel says. The report echoes previous calls for the agency to put more money into small, rapidly deployable missions – even if it means taking money from bigger missions. The review of NASA’s progress in astrophysics, released on Wednesday, was prepared by the US National Research Council (NRC) in response to a 2005 directive from Congress. It warns of a four-year gap between 2009, when the WISE (Wide-field Infrared Survey Explorer) mission lifts off to study nearby stars and embryonic planetary systems, and 2013, when Hubble’s successor, the James Webb Space Telescope (JWST), is due to launch. The gap is the result of a NASA astrophysics portfolio that is “heavily skewed toward support of the largest missions”, leaving little money for smaller missions that can be launched more frequently, the report says. It is particularly critical of NASA’s lack of funding for its Explorer programme, which develops small, inexpensive missions that cost less than $180 million. NASA has launched six Explorer-class missions since 2000, including the Wilkinson Microwave Anisotropy Probe (WMAP) – which studies the glow leftover from the big bang – and the Swift satellite, which studies gamma-ray bursts. But NASA has no new Explorer-class missions planned for launch in the next decade. The report calls on NASA’s astrophysics division to restore funding for the Explorer class, which “may require the division to scale back larger programmes that are currently in development.” It does not specify which programmes should be scaled back, but notes elsewhere that unexpectedly large costs for JWST have left less money for other projects. The criticism of NASA’s focus on large missions echoes concerns raised a year ago when NASA made its 2007 budget request (see Criticism of NASA science budget grows). But the agency has not changed tack since (see Science funding stays flat in NASA budget). Compounding the problem is the fact that the US Air Force says that after 2009, it will stop supporting launches of its Delta II rocket – a favourite launch vehicle for small- and medium-size missions. The Mars rovers Spirit and Opportunity were launched on Delta II rockets. “In a time of extraordinary potential for scientific discovery, the prospects for future contributions to astrophysics by NASA have been substantially reduced,” the report says. It adds that as a result,