NASA’s Science Mission Directorate (SMD) is releasing this Community Announcement concerning its intention to solicit investigations for the Heliophysics Explorer Program. The Heliophysics Explorer Program conducts Principal Investigator (PI)-led space science investigations to advance NASA’s strategic objective in heliophysics, which is to “Understand the Sun and its interactions with the Earth and the solar system, including space weather.” Additional information concerning these areas of investigation is provided through appropriate links found on the SMD homepage athttp://science.nasa.gov/heliophysics/.

The current state of planning calls for NASA SMD to release an Announcement of Opportunity (AO) in the Spring/early Summer of 2016 that will solicit proposals for Small Explorer (SMEX) missions to accomplish Heliophysics Explorer Program science objectives. NASA also plans to simultaneously release a solicitation for Heliophysics Explorer Missions of Opportunity (MO) through a NASA Announcement of Opportunity, Second Stand Alone Missions of Opportunity Notice (SALMON-2). A draft SMEX AO and draft SALMON-2 Program Element Appendix (PEA) are expected to be ready for release for comment in Winter 2015.

The schedule for the solicitation is intended to be:

Release of draft AO (target):                                   Winter 2015
Explorer workshop:                                                  ~1 month after draft AO release;
Release of final AO (target):                                    Spring/early Summer 2016
Preproposal conference:                                         ~3 weeks after final AO release;
Proposals due:                                                         90 days after AO release;
Selection of Phase A studies (target):                  early Spring 2017
Concept study reports due (target):                       early Spring 2018
Down-selection (target):                                          late Summer/Fall 2018