JDEM
The Joint Dark Energy Mission (JDEM) was an Einstein probe that planned to focus on investigating dark energy. JDEM was a partnership between NASA and the U.S. Department of Energy.
In August 2010, the Board on Physics and Astronomy of the National Science Foundation recommended the Wide Field Infrared Survey Telescope (WFIRST) mission, a renamed JDEM-Omega proposal which has superseded SNAP, Destiny, and ADEPT, as the highest priority for development in the decade around 2020. This would be a 1.5-metre telescope with a 144-megapixel HgCdTe focal plane array, located at the L2 Lagrange point. The expected cost is around $1.6 billion.
The Dark Energy Space Telescope (Destiny), was a planned project by NASA and DOE, designed to perform precision measurements of the universe to provide an understanding of dark energy. The space observatory will derive the expansion of the universe by measuring up to 3,000 distant supernovae each year of its three-year mission lifetime, and will additionally study the structure of matter in the universe by measuring millions of galaxies in a weak gravitational lensing survey. The Destiny spacecraft features an optical telescope with a 1.65m primary mirror. The telescope images infrared light onto an array of solid-state detectors. The mission is designed to be deployed in a halo orbit about the sun-earth L2 Lagrangian point.
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