On or about October 21, 2016, the National Aeronautics and Space Administration (NASA) Science Mission Directorate (SMD) is releasing an Astrophysics Explorers 2016 Mission of Opportunity (MO) Program Element Appendix (PEA) (NNH12ZDA006O-APEXMO3) Amendment as Amendment 17 to the NASA Second Stand Alone Missions of Opportunity Notice (SALMON-2) Announcement of Opportunity (NNH12ZDA006O). Upon the release date, the full text will be available at http://nspires.nasaprs.com/.

The deadline for the submission of a notice of intent to propose (NOI) has been changed
to October 27, 2016.

Please note that the Deadline for Proposal Submission remains December 15, 2016.

Questions may be addressed in writing or by E-mail to: Dr. Wilton T. Sanders, Astrophysics Explorers Program Scientist, Astrophysics Division, Science Mission Directorate, NASA Headquarters, Washington, DC 20546-0001; E-mail: [email protected] (subject line to read "Explorer MO PEA"); Phone: 202-358-1319; FAX: 202-358-3062. Responses to all inquiries will be answered by E-mail and also posted to the Questions and Answers (Q&A) location of the 2016 Astrophysics Explorers Program Acquisition website at http://explorers.larc.nasa.gov/APMIDEX2016/MO; anonymity of persons and institutions who submit questions will be preserved.