Mission analysis and preliminary spacecraft design of the enhanced x-ray timing and polarimetry observatory

Event: Space Telescopes and Instrumentation 2020: Ultraviolet to Gamma Ray, 114442E (13 December 2020).
The enhanced X-ray Timing and Polarimetry Observatory (eXTP) is a flagship international collaboration mission led by Chinese Academy of Sciences, with a large contribution from more than 20 European institutes. eXTP mission is designed to study the equation of state of ultra-dense matter under extreme conditions of strong density, gravity and magnetic field. The satellite carries four main instruments, including the Spectroscopy Focusing Array (SFA), the Large Area Detector (LAD), the Polarimetry Focusing array (PFA) and the Wide Field Monitor (WFM), enabling simultaneous spectral-timing-polarimetry studies of celestial sources in the energy range from 0.5-30 keV. The satellite will fly at a near-zero-inclination Low Earth Orbit, and is featured with long-time steady high-precision coaxial pointing, near realtime burst alert distribution, and follow-up maneuver capabilities. This paper describes the primary mission requirements and constraints, and presents an overall mission analysis including orbit analysis, pointing strategy, and board-ground communications, etc. The preliminary design of eXTP satellite is also introduced, including satellite overall configuration, observation modes, avionics architecture and development plan.
The mission is led by China, currently supported by Chinese Academy of Sciences and executed under the management of the National Space Science Center of CAS. The project has officially kicked off Phase B in November 2019. After Phase C1, official mission adoption is expected. With Phase C2 and Phase D planned in 2023-2027, the eXTP satellite is targeted to be launched in 2027.