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X-Ray Timing Explorer



The X-Ray Timing Explorer (XTE) mission has the primary objective to study the temporal and broad-band spectral phenomena associated with stellar and galactic systems containing compact objects in the energy range 2--200 KeV, and in time scales from microseconds to years. The scientific instruments consists of two pointed instruments, the Proportional Counter Array (PCA) and the High-Energy X-ray Timing Experiment (HEXTE), and the All Sky Monitor (ASM), which scans over 70% of the sky each orbit. All of the XTE observing time will be available to the international scientific community through a peer review of submitted proposals. XTE uses a new spacecraft design that allows flexible operations through rapid pointing, high data rates, and nearly continuous receipt of data at the Science Operations Center at Goddard Space Flight Center via a Multiple Access link to the Tracking and Data Relay Satellite System (TDRSS). XTE is highly maneuverable with a slew rate of greater than 6 degrees per minute. The PCA/HEXTE can be pointed anywhere in the sky to an accuracy of less than 0.1 degree, with an aspect knowledge of around 1 arc-minute. Rotatable solar panels enable anti-sunward pointing to coordinate with ground-based night-time observations. Two pointable high gain antennas maintain nearly continuous communication with the TDRSS. This, together with 1 GB (approximately four orbits) of on-board solid-state data storage, give added flexibility in scheduling observations.

Alternate Names

  • 23757
  • Explorer 69
  • RXTE
  • Rossi X-Ray Timing Explorer
  • X-RayTimingExplorer
  • XTE

Facts in Brief

Launch Date: 1995-12-30
Launch Vehicle: Delta II 7920
Launch Site: Cape Canaveral, United States
Mass: 3200 kg
Nominal Power: 800 W

Funding Agency

  • NASA-Office of Space Science Applications (United States)


  • Astronomy

Additional Information

Questions and comments about this spacecraft can be directed to: Coordinated Request and User Support Office



NameRoleOriginal AffiliationE-mail
Mr. James B. JoyceMission Operations ManagerNASA Goddard Space Flight
Mr. Dale F. SchulzProject ManagerNASA Goddard Space Flight
Dr. John LintottProgram ManagerNASA Goddard Space Flight Center
Mr. William D. DavisMission ManagerNASA Goddard Space Flight
Dr. Richard E. RothschildMission Principal InvestigatorUniversity of California, San Diego
Dr. Jean H. SwankProject ScientistNASA Goddard Space Flight
Mr. James S. BarrowmanProject ManagerNASA Goddard Space Flight
Dr. Louis J. KaluzienskiProgram ScientistNASA Headquarters
Dr. Llewellyn W. NicholsonMission ManagerNASA Goddard Space Flight Center
Dr. Hale V. BradtMission Principal InvestigatorMassachusetts Institute of

US Active Archive for XTE Information/Data

The RXTE Archive at HEASARC

Other Sources of XTE Information/Data

MIT All Sky Monitor team page
UCSD High Energy X-ray Timing Experiment (HEXTE) team page
GSFC Proportional Counter Array (PCA) Team

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