NASA should think twice before moving ahead with two separate missions to find extrasolar planets, says a National Academy of Sciences report requested by the space agency in January and released this week.
NASA initially intended to pursue just one of two methods for detecting distant Earth-sized planets that might harbor life: an infrared interferometer, or a coronagraph for the Terrestrial Planet Finder probe. But in January, NASA decided to do both. The coronagraph would be launched in 2014, followed in 2020 by a joint U.S.-European interferometer.
The possibility of combining data from both missions is intriguing, said the 11-member academy panel led by Wendy Freedman of the Carnegie Observatories in Pasadena, California. But NASA needs to make a stronger scientific case for the coronagraph mission, which it describes as "expensive and challenging." Ultimately, funding both missions could "delay or even preclude" other space science efforts listed in the community's 2000 decadal plan, the panel says. NASA has not yet responded to the report.
