Last year a committee from the National Academy of Sciences recommended that a dark energy observatory be the next mission in an astrophysics program called Beyond Einstein.
There are now three competitors angling for the job: Dr. Perlmutter’s SNAP, for Supernova Acceleration Probe; Adept, or Advanced Dark Energy Telescope, led by Charles Bennett of Johns Hopkins; and Destiny, for Dark Energy Space Telescope, led by Tod Lauer of the National Optical Astronomy Observatory in Tucson.
Also in the works, just to add spice, is a European mission known as Euclid, which could fly in 2017, if it is approved by the European Space Agency. NASA and the Department of Energy, working together, expect to make a final selection for the dark energy mission — known colloquially as J-dem for Joint Dark Energy Mission — next spring and launch it in the middle of the next decade.
That sounds like progress, but some astronomers, including the former members of the academy committee itself, have complained that $600 million is less than half of the $1.2 billion to $1.5 billion the academy committee estimated was necessary to do the job. In a recent letter to Michael Salamon, NASA scientist in charge of the project, 11 of the committee members, including both of its chairmen, urged NASA to raise the cost cap on the mission, writing, “Cutting the budget in half would probably make the attainment of these goals impossible.”
NASA’s $600 million does not include the cost of launching the satellite, so the discrepancy is not as big as it looks. But in Baltimore, Jon Morse, director of astrophysics at NASA headquarters, warned that if the astronomers wanted to spend a billion dollars, some other astronomy mission would have to come off the table.
After Years of Effort, Dark Energy Still Puzzles Scientists - NYTimes.com
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