More subtly, they have also learned to broaden their perspective on time, looking for events that happen so quickly that we might never notice them. It focuses on the energetic X-rays that originate in violent processes occurring around hyperdense objects such as neutron stars and black holes . The x-ray sky looks very different than the familiar one. When seen though RXTE' s eyes, the sky flares with radiation from a class of variable stars known as x-ray binaries . In either case, the collapsed star's powerful gravity snatches material from its partner, a more sedate star like the sun.
Gas spiraling inward grows fiercely hot, emitting the observed X rays.
In some instances, the gas collects on the star's surface until it reaches a critical mass, touching off a tremendous thermonuclear detonation. But using RXTE, people like Tod E. Strohmayer of the NASA Goddard Space Flight Center are starting to find out. M. Coleman Miller of the University of Chicago thinks the X-ray stuttering is a kind of beat pattern that results from the overlapping periods of the neutron star's rotation and the cyclic orbiting of hot gas about to crash onto the star's surface. For the first time, it seems, we can actually watch a neutron star feeding. Related RXTE studies may finally settle the mystery concerning the origin of a group of astronomical speedsters called millisecond pulsars.