2023 Astrophysics Probe Explorer (APEX) Announcement of Opportunity

This SAM.gov amendment announces that the final text of 2023 APEX AO has been revised. Open and carefully read the attached PDF file entitled “ NNH23ZDA021OAmend1Summary.” On or after the publication date of this SAM.gov special notice, the final full text for the Announcement of Opportunity (AO) for 2023 Astrophysics Probe Explorer (APEX) 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 “NNH23ZDA021O” in the search box or use the direct URL provided below. It is necessary to download or open and carefully read the attached summary PDF file entitled “NNH23ZDA021OSummary” for other important dates, i.e., Mandatory Notice of Intent to Propose, Pre-Proposal Conference, etc., that are prior to the listed Date Offers Due. The attached PDF file is a copy of an email to be sent via NSPIRES to Science Mission Directorate List Serv subscribers. After reading the full APEX AO on NSPIRES, please address any comments and questions only via email to both the listed primary and secondary points of contact and use "APEX 2023 AO" in the subject line. This SAM.gov notice is not a complete or verbatim summary of the AO.