2026 Astrophysics Small Explorer (APSMEX)
NASA will fund a selected Astrophysics Small Explorer mission team to carry out a small astrophysics space science mission under the 2026 Astrophysics Explorers Program.
RESTRICTED TO: SINGLE NAMED INSTITUTION
⚑ Federal contract / solicitation, not a grant. · Mandatory notice of intent and preproposal conference are mentioned in the full AO. · Check NSPIRES attachments and amendments; deadline is controlled by the AO text. · Applicant restrictions are stated in the notice but not specified in the excerpt.
Unit fits — one characterization, each unit's own rules
| IPPRA | 5 none | limited competition — a named institution holds this |
| Tom Love Innovation Hub | 5 none | not openly competed |
| Physical Sciences & Engineering (demo) | 5 none | limited competition — a named institution holds this |
Description
Amendment #1: This SAM.gov update 1) announces the release of revised final text for the “Astrophysics Explorers Program 2026 Small Explorer (SMEX)” AO and 2) adds a copy of the text of an August 2026 NSPIRES e-mail sent to SMD List Serv subscribers. Please open and carefully review the attachment named “6AugustEmail.pdf” under the Attachments/Links section of this notice. The proposal due date remains unchanged. For complete details, visit the link named “Final Ful Text NNH26ZDA011O” under the Attachments/Links section of this notice. End of Amendment #1. On or after this SAM.gov notice, the final text for the Announcement of Opportunity (AO) 2026 Astrophysics Small Explorer (APSMEX) will be available for download from the NASA Solicitation and Proposal Integrated Review and Evaluation System (NSPIRES) at https://nspires.nasaprs.com. Click on the word “Solicitations” at the top of the NSPIRES landing page and then on the next page enter the number “NNH26ZDA011O” in the search box or use the direct URL provided below. This “Description” is not a complete or verbatim summary of the AO. It is the responsibility interested parties to visit and monitor regularly the two listed internet sites (links) for any amendments or other updates. Please also open and carefully read the attached PDF file named “9JuneEmail.pdf”. The 9JuneEmail attachment is copy of the text that NSPIRES sent to Science Mission Directorate (SMD) List Serv subscribers and includes other and earlier, important dates such as for the submission of a MANDATORY Notice of Intent (NOI) and a virtual Preproposal conference that are prior to the listed Date Offers Due. After reading the full AO on NSPIRES, please address any comments and questions only via email to both the primary and alternative points of contact listed and use " APSMEX26” in the subject line.
Eligibility
Applicant restrictions (federal contract). Set-aside: . Notice type: Combined Synopsis/Solicitation. Organization: NATIONAL AERONAUTICS AND SPACE ADMINISTRATION / NATIONAL AERONAUTICS AND SPACE ADMINISTRATION / NASA HEADQUARTERS.
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Proposal brief SEE AN EXAMPLE →
A one-page internal memo: fit assessment, submission requirements, document scaffold, and next steps dated back from the deadline — tailored to your project idea if you add one.
Proposal shell · Federal (generic) conventions SEE A FEDERAL EXAMPLE →
Funder-faithful document skeletons — Federal (generic)'s document set with section headings, page limits, reviewer guidance, and writing prompts; add a project idea to get [DRAFT] starter bullets. Download as .md for Word or Overleaf.