FINAL -- 2021 Astrophysics Medium Explorer (MIDEX) Announcement of Opportunity (AO)

NASA seeks proposals through its 2021 Astrophysics Medium Explorer Announcement of Opportunity and 2021 Astrophysics Explorers Mission of Opportunity Program. NASA will consider proposals for approximately 2-3 MIDEX missions to receive Phase A studies, with one to be downselected for Phases B and beyond. Additionally, NASA will consider proposals for approximately 2 or more Mission of Opportunity proposals to receive Phase A studies, with one or more to be downselected for Phases B and beyond. The deadline for Notice of Intent submissions is November 4, 2021 and the deadline for proposals is December 9, 2021. Questions must be submitted by three weeks prior to the proposal deadline and responses will be issued by NASA ten days prior to the deadline.

There is no set-aside designation. The primary NAICS codes are 541715 and 927110, covering research and development in the physical, engineering, and life sciences as well as space research and technology. NASA anticipates selecting proposals to receive Phase A study awards valued between $500,000 to $3 million, with missions expected to be performed over multiple years at contractor and NASA facilities nationwide.