PHASE A WORK FOR ASTMOSPHERE-SPACE TRANSITION REGION EXPLORER (ASTRE) UNDER ANNOUCEMENT OF OPPORTUNITY NNH11ZDA002O FOR WORK TO BE PERFORMED BY ORBITAL SCIENCES CORPORATION. THE CONTRACTOR SHALL PROVIDE A MONTHLY WRITTEN PROGRESS REPORT. THE CONTRACTOR SHALL PARTICIPATE IN WEEKLY TELECONS TO REPORT PROGRESS, STATUS ACTIONS ITEMS, AND RAISE AND DISCUSS TECHNICAL ISSUES OR PROBLEMS. THE CONTRACTOR SHALL REVIEW THE MISSION DESIGN, MISSION REQUIREMENTS, AND MISSION REQUIREMENTS FLOW DOWN AND PROVIDE COMMENTS. THE CONTRACTOR SHALL DOCUMENT KEY SPACECRAFT AND SPACECRAFT SUBSYSTEM LEVEL REQUIREMENTS BASED ON THE MISSION REQUIREMENTS FLOW DOWN. THE CONTRACTOR SHALL REVIEW THE MISSION CONCEPT OF OPERATIONS, INCLUDING LAUNCH, DEPLOYMENT, SCIENCE OPERATIONS, COMMUNICATIONS, AND END-OF-MISSION, AND PROVIDE COMMENTS. THE CONTRACTOR SHALL PROVIDE SPACECRAFT INPUTS TO THE INTERFACE CONTROL REQUIREMENTS (ICR) DOCUMENT AND SHALL REVIEW AND PROVIDE COMMENTS ON THE COMPLETED ICR. THE CONTRACTOR SHALL SUPPORT AND REVIEW DEFINITION OF THE OBSERVATORY-GROUND, MOC-SOC, AND OBSERVATORY TO LAUNCH VEHICLE INTERFACES.THE CONTRACTOR SHALL REVIEW AND REFINE THE SPACECRAFT BUDGETS INCLUDING MASS, POWER, POINTING, COMMUNICATIONS, DATA STORAGE AND PLAYBACK, PROPULSION, RELIABILITY AND OTHER MARGINS REQUIRED FOR PHASE A AND PROVIDE ANALYSIS RESULTS. THE CONTRACTOR SHALL PROVIDE I&T FLOWS FOR THE SPACECRAFT ASSEMBLY, INTEGRATION AND TEST AND THE OBSERVATORY ASSEMBLY. THE CONTRACTOR SHALL PARTICIPATE IN THE ASTRE RISK PROCESS. THE CONTACTOR SHALL UPDATE AND REFINE THE SPACECRAFT AND SPACECRAFT SUBSYSTEM DESIGNS TO MEET MISSION AND SPACECRAFT LEVEL REQUIREMENTS AS NECESSARY.