2021 Astrophysics Small Explorer (MIDEX) MO

2021 Astrophysics Medium Explorer (MIDEX) MO


2021 Astrophysics Explorer MIDEX Mission of Opportunity



The National Aeronautics and Space Administration (NASA) issues this DRAFT Third Stand Alone Missions of Opportunity Notice (SALMON-3) Program Element Appendix (PEA) for the purpose of soliciting proposals for Astrophysics Mission of Opportunity (MO) science investigations to be implemented through its Explorers Program.

Since the early 1990s, the Explorers Program has provided several types of flight opportunities for addressing astrophysics and heliophysics science objectives. These mission types are defined by their Cost Caps and are designed to increase the number of flight opportunities in response to recommendations from the scientific community. The Explorers Program currently consists of two types: larger stand-alone "full missions," for which NASA offers a dedicated launch vehicle, and smaller investigations called "missions of opportunity" (MOs).