X-ray timing explorer mission

The XTE will address a number of fundamental questions about the nature of the cosmos. The large effective area (about 0.8 sq m total) and broad band of sensitivity (2-200 keV) of its three instruments make it especially valuable for timing of intensity variations and for the determination of broadband spectra from high-energy sources. For the first time, studies of variability ranging from about 1 microsecond to several years will be carried out. XTE's design and flexibility of operations will allow it to respond rapidly to changes in the X-ray sky (within hours) and will facilitate multifrequency observations. It is scheduled for launch on a Delta II vehicle prior to April 1996.