NASA's XRISM Mission Observes Pulsar Capturing Stellar Wind, Advancing Understanding of Extreme Universe
The National Aeronautics and Space Administration (NASA), in collaboration with the Japan Aerospace Exploration Agency (JAXA), has utilized data from the X-ray Imaging and Spectroscopy Mission (XRISM) observatory to directly observe a pulsar capturing stellar wind from its companion star. This phenomenon, where a giant star's outflow (stellar wind) is captured by a compact object, powers strong X-ray flares. The research, published in the journal Science Advances, focuses on the BP Crucis system, a high-mass X-ray binary located approximately 13,000 light-years away. The system consists of Wray 977, a blue hypergiant 40 times the Sun's mass, and GX 301-2, a neutron star (pulsar) that rotates every 11 minutes. The XRISM's Resolve instrument captured highly detailed X-ray spectra, revealing rapidly changing emission and absorption lines, particularly from highly ionized iron, which indicated the speed and direction of plasma near the pulsar. This marks the first time clear indications of wind plasma falling ...