USA. Each year The NASA award approximately 50 research fellowships through The NASA Postdoctoral Program (NPP). NPP is open to any PhD (or equivalent doctorate degree) holders who is interested to engage in ongoing NASA research programs at a NASA Center, NASA Headquarters, or at a NASA-affiliated research institution.
These one- to three-year Fellowship appointments are administered by Oak Ridge Associated Universities (ORAU) and are designed to advance NASA’s missions in space science, earth science, aeronautics, space operations, exploration systems, and astrobiology. The annual stipends would be started at US$50,000 with additional Annual travel budget of US$8,000.
You may apply as either a Postdoctoral Fellow or a Senior Fellow. A Postdoctoral Fellow has held the doctoral degree for less than five years at the time of application. A Senior Fellow has held the doctoral degree for five or more years at the time of application.
Eligibility
Annual application deadlines are March 1st, July 1st, and November 1st. The NASA Centers receive the results from the application reviews approximately two months following each application deadline. ORAU will notify applicants regarding the status of their applications when NASA makes the selection for awards.
Further details including application form can be obtained from the NASA Postdoctoral Program official site. and also from ORAU site (application info).