XRISM first sees stellar wind feeding pulsar GX 301-2's X-ray flares

Astronomers using the XRISM telescope have directly observed stellar wind plasma falling onto a compact object for the first time — pulsar GX 301-2 in the BP Crucis system, about 13,000 light-years away. Its X-ray flares occur as it passes through a plasma plume from hypergiant Wray 977 streaming at 540,000 km/h.

• Pulsar GX 301-2, about 20 km across, orbits Wray 977 every 41.5 days
• The hypergiant's plasma plume reaches speeds of 540,000 km/h
• The 16-hour observation coincided with a pulsar flare
• Findings published in Science Advances on Sept. 18