Chinese satellite likely captured black hole devouring white dwarf for 1st time

China's Tianguan satellite, also called the Einstein Probe, has likely recorded an intermediate-mass black hole ripping apart and consuming a white dwarf, Xinhua News reported on Thursday.

According to the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), it marks the first time such an extreme event has been observed

During a routine sky survey on July 2, 2025, the satellite spotted an exceptionally bright, rapidly varying X-ray source, named EP250702a.

The burst's brightness, radiation pattern, and spectral features differed sharply from any known cosmic explosion.

In a cover article in the latest issue of Science Bulletin, the NAOC team proposed that the event was likely a tidal disruption of a white dwarf by an intermediate-mass black hole.

"This phenomenon closely resembles the rare occurrence of a jetted tidal disruption event, where a black hole tears apart a star," explained Zhang Wenda, an associate researcher at the NAOC.

A white dwarf is the extremely dense remnant of a dead star, with an average density up to a million times that of the Sun.

Theories indicate that only intermediate-mass black holes — ranging from hundreds to hundreds of thousands of solar masses — have tidal forces powerful enough to tear apart such a compact object instead of swallowing it whole.

This process is expected to generate a short, intense burst of energy, likely with a bright, fast-moving jet, matching the rapid evolution and extreme brightness seen in EP250702a.

"The ultra-short timescale, extreme peak luminosity, and the subsequent emergence of a soft X-ray 'afterglow' strongly supported the scenario of a medium-mass black hole ripping apart a white dwarf," said Jin Chichuan, a researcher at the NAOC.