Solicitation Notice: NATIONAL AERONAUTICS AND SPACE ADMINISTRATION is seeking proposals for the Geostationary Extended Observations (GeoXO) Spacecraft (SC) Phase B Implementation. The GeoXO Program aims to procure spacecraft for the GeoXO series, which includes an east, west, and center spacecraft. These three-axis stabilized geostationary spacecraft will support three instruments each, with the east and west spacecraft also supporting an auxiliary communication payload for the NOAA Data Collection System (DCS). The procurement includes a total of seven spacecraft, with launches planned for the first six and the seventh spacecraft having no current launch date. The contract scope involves designing, analyzing, developing, fabricating, integrating, testing, evaluating, and supporting the launch of the GeoXO spacecraft. It also includes providing Engineering Development Units (EDUs), supplying and maintaining Ground Support Equipment (GSE) and simulators, and supporting mission operations at the NOAA Satellite Operations Facility (NSOF). The spacecraft has a risk classification of Class B. The acquisition will be conducted as a full and open competition, with a Cost-Plus-Award-Fee (CPAF) hardware contract anticipated. The contract will have a period of performance of 15 years for each Flight Model (FM), including 10 years of on-orbit operations and 5 years of on-orbit storage. The contract will also allow for special study tasks for risk reduction and mitigation activities, with a maximum dollar amount of $35,000,000. The anticipated contract award date is late May 2024. Interested offerors should ensure their company is listed in the required online databases. The successful offeror must pass an Equal Employment Opportunity (EEO) clearance before contract award. Proposals are due by November 30, 2023, and must be submitted through NASA's Enterprise File Sharing and Sync Box (EFSS Box). All inquiries and communications should be directed to the Contracting Officer.