NASA is clarifying the 2019 Explorer SMEX AO to correct a series of typographical errors resulting from a misplaced designation for Requirement 97.  The AO has 100 Requirements not 101 as originally published.  The proposal due date is unchanged and remains August 1, 2019.  Since this is an FBO notice, it is not a complete or verbatim summary of the SMEX AO and any appendices nor any, if necessary, future amendments or clarifications.  The full SMEX amendment text is available at https://nspires.nasaprs.com by searching on "NNH19ZDA011O" or "SMEX" upon the amendment's release date.

Comments and questions may be addressed by email only to: Dr. Linda S. Sparke, Astrophysics Explorers Program Scientist, Astrophysics Division, Science Mission Directorate, NASA Headquarters, Washington, DC 20546-0001, E-mail: [email protected] (subject line to read "Explorer SMEX AO").  The period for questions/comments will close three weeks before the proposal due date, and the period for responses will close ten days before the proposal due date.

Responses to all inquiries will be posted as Questions and Answers QAs.   SMEX QAs are linked from the 2019 Astrophysics Explorers Program Acquisition website at https://explorers.larc.nasa.gov/2019APSMEX/SMEX/index.html.  Anonymity of persons and institutions who submit questions will be preserved.

In the event of Government funding lapses that impact NASA operations, proposers should visit NSPIRES, the official NASA source for the full SMEX Announcement of Opportunity.