On 2 July, 2025, the China-led Einstein Probe (EP) space telescope detected an exceptionally bright X-ray source whose brightness varied rapidly during a routine sky survey. Its unusual signal immediately set it apart from ordinary cosmic sources, triggering rapid follow-up observations by telescopes worldwide.

This research was coordinated by the EP Science Center of the National Astronomical Observatories, Chinese Academy of Sciences (NAOC), with participation from multiple research institutions in China and abroad. Astrophysicists from the Department of Physics at The University of Hong Kong (HKU), who are integral members of the EP scientific team, worked together with the broader collaboration to interpret the event, proposing that it may mark the moment when an intermediate-mass black hole tears apart and consumes a white dwarf star. If confirmed, this would be the first observational evidence of such an extreme black hole “feeding” process. The findings have been published as a cover article in Science Bulletin.

Inspired by the human visual system, scientists in China have developed a bioinspired phototransistor with tunable sensitivity that significantly enhances the detection of low-contrast targets. By embedding a reverse-biased photodiode into the gate structure, the device achieves dynamic voltage redistribution and light-dependent conductance tuning, boosting sensitivity by more than 1000 times. The technology offers a powerful new strategy for intelligent machine vision under complex illumination.

A team of astronomers led by the Flatiron Institute’s Kishalay De discovered that a star in the Andromeda Galaxy disappeared without going supernova, and instead collapsed directly into a black hole. The team’s analysis of the star, reported in Science, reveals what happened and helps explain why some massive stars turn into black holes while others don’t.