Free Astronomy Magazine March-April 2026

43 MARCH-APRIL 2026 ASTRO PUBLISHING ! galaxy along the line-of-sight be- tween Earth and the GRB source. These details about the environment of GRB 250702B provide important constraints on the system that pro- duced the initial outburst of gam- ma-rays. Of the roughly 15,000 GRBs observed since the phenomenon was first recognized in 1973, only a half dozen come close to the length of GRB 250702B. Their proposed ori- gins range from the collapse of a blue supergiant star, a tidal disrup- tion event, or a newborn magnetar. GRB 250702B, however, doesn’t fit neatly into any known category. From the data obtained so far, scien- tists have a few ideas of possible ori- gin scenarios: (1) a black hole falling into a star that’s been stripped of its hydrogen and is now almost purely helium, (2) a star (or sub-stellar ob- ject such as a planet or brown dwarf) being disrupted during a close encounter with a stellar com- pact object, such as a stellar black hole or a neutron star, in what is known as a micro-tidal disruption event, (3) a star being torn apart as it falls into an intermediate-mass black hole — a type of black hole with a mass ranging from one hun- dred to one hundred thousand times the mass of our Sun that is be- lieved to exist in abundance, but has so far been very difficult to find. If it is the latter scenario, this would be the first time in history that humans have witnessed a relativistic jet from an intermediate mass black hole in the act of consuming a star. While more observations are needed to conclusively determine the cause of GRB 250702B, the data acquired so far remain consistent with these novel explanations. “This work pres- ents a fascinating cosmic archaeol- ogy problem in which we’re re- constructing the details of an event that occurred billions of light-years away,” says Carney. “The uncovering of these cosmic mysteries demon- strates how much we are still learn- ing about the Universe’s most ex- treme events and reminds us to keep imagining what might be hap- pening out there.”