Explorer: XTE (RXTE, Rossi)

The XTE (X-Ray Timing Explorer), RXTE (Rossi X-Ray Timing Explorer) 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,

• Proportional Counter Array (PCA) has five xenon gas proportional counter detectors (2 - 60 keV). The PCA has a large collecting area (6250 cm2).
• High Energy X-ray Timing Experiment (HEXTE) extends the X-ray sensitivity of RXTE up to 200 keV

and the All Sky Monitor (ASM), which scans over 70% of the sky each orbit.

• All Sky Monitor (ASM) rotates in such a way as to scan most of the sky every 1.5 hours, at 2-10 keV, monitoring the long-term behavior of a number of the brightest X-ray sources.

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.

XTE was originally designed as a exchangeable payload module for the EUVE spacecraft, but after the Shuttle service mission was cancelled, XTE was redesigned as a non-serviceable freeflyer.

Last update: 27.09.2009
Contact: gunter.krebs@skyrocket.de
© Gunter Dirk Krebs