DRAFT Announcement of Opportunity (AO) -- 2025 Astrophysics Small Explorer (SMEX)

2nd Amendment: NASA is reactivating and amending this special notice to announce 1) a new primary POC; 2) that the release of the final AO text is expected no earlier than the 2nd quarter of calendar year 2026; and 3) to add a PDF file named “3rdNSPIRESemail”. After reading this 3rd PDF file, only via email contact both the listed primary and secondary points of contact and use "2026 SMEX AO" in the subject line. 1st Amendment: NASA is reactivating and amending this special notice to announce 1) that the release of the final AO text is postponed and 2) to add a PDF file named “2ndNSPIRESemail”. Only after reading this 2nd PDF file, only via email contact both the listed primary and secondary points of contact and use "DRAFT 2025 SMEX AO" in the subject line. On or after the publication date of this SAM.gov special notice, the DRAFT full text for the Announcement of Opportunity (AO) for the 2025Astrophysics Small Explorer (SMEX) will be available for download from the NASA Solicitation and Proposal Integrated Review and Evaluation System (NSPIRES) at https://nspires.nasaprs.com. When you reach NSPIRES, click on the word “Solicitations” at the top of the NSPIRES landing page and then on the next page enter the number “NNH25ZDA008J” in the search box or use the direct URL provided below to the SMEX page on NSPIRES. The attached file entitled “1stNSPIRESemail” is a copy of text from an NSPIRES email sent to Science Mission Directorate List Serv subscribers. After reading the full SMEX draft AO text available from NSPIRES, please address any comments and questions only via email to both the listed primary and secondary points of contact and use "DRAFT 2025 SMEX AO" in the subject line. This SAM.gov notice is not a complete or verbatim summary of the draft AO.