XTE

The Rossi X-ray Timing Explorer (RXTE) was a satellite that observed the time variation of astronomical X-ray sources, named after physicist Bruno Rossi. The RXTE had three instruments—an All-Sky Monitor, the Proportional Counter Array, and the High-Energy X-ray Timing Experiment (HEXTE). The RXTE observed X-rays from black holes, neutron stars, X-ray pulsars, and X-ray bursts.