Habitable Worlds Observatory Instrument Concept Assessments in NASA Research Announcement (NRA): RESEARCH OPPORTUNITIES IN SPACE AND EARTH SCIENCES (ROSES) 2025

Amendment #1 (09/03/2026): This Amendment adds the "2ndEmail" attachment which summarizes the following changes under ROSES-2025 Amendment 73: Section 3.3.2 has been updated regarding Collaborators on Category 2 proposals. It now allows that unfunded U.S.-based individuals involved in the proposed work may be included as Collaborators. New text is in bold in the ROSES Amendment 73. The due date remains unchanged: Proposals are due by October 14, 2026. In addition, the FAQ has also been updated. NASA will accept questions up until September 18, 2026. The attached PDF file labeled �1stEmail� is text that the NASA Solicitation and Proposal Integrated Review and Evaluation System (NSPIRES) sent to Science Mission Directorate (SMD) List Serv subscribers. This �1stEmail� attachment announces the release of the full text for NNH25ZDA001N-HWOICA as well as summarizes key information from the full text. Visit the link below labeled �NSPIRES page for NNH25ZDA001N-HWOICA� to download the full text. SMD may periodically clarify or amend the solicitation or add other supporting documents. Interested parties should regularly visit the HWOICA NSPIRES page to stay up-to-date on any such changes. In the event of a NASA funding lapse on or after 1 October 2026, please visit NSPIRES.