我国卫星捕捉到罕见黑洞“进食”现场

Core Viewpoint - The "Tian Guan" satellite has captured an unprecedented event involving a medium-mass black hole tearing apart and consuming a white dwarf star, marking the first time such an extreme black hole "feeding" event has been observed by humanity [1][3]. Group 1: Discovery and Observation - The "Tian Guan" satellite detected an unusually bright and rapidly changing X-ray source, designated EP250702a (also known as GRB 250702B), during its routine sky survey [1][3]. - This event's brightness variation, radiation rhythm, and spectral characteristics are significantly different from any previously known outbursts, prompting a global observational effort using multiple telescopes [1][3]. Group 2: Scientific Explanation - The research team proposed that the observed phenomenon is likely a medium-mass black hole ripping apart and consuming a white dwarf star, which is a dense remnant left after a star's death [3]. - The average density of a white dwarf can reach up to one million times that of the Sun, and only medium-mass black holes, with masses between hundreds to hundreds of thousands of solar masses, can effectively tear apart such a dense object without "gulping" it whole [3]. Group 3: Implications and Contributions - The findings provide strong support for the theory of a medium-mass black hole tearing apart a white dwarf, characterized by extremely short timescales, high peak luminosity, and soft X-ray "afterglow" observed post-explosion [3]. - The discovery of EP250702a highlights the unique monitoring capabilities of the "Tian Guan" satellite and underscores China's contributions to global astronomical exploration [3].