Ruchika Dhaka

During its 2021 outburst, the black hole in the GX 339-4 system behaved like an actress changing costumes between scenes. In the hard state, it wore two coronas at once: a hot, rarefied one, and over it, a warm, dense one. In the soft state, only the hot corona remained.

The black hole in GRS 1915+105 behaves like a lighthouse with a shaky foundation: its jet, normally aimed in one direction, suddenly veered off by 34 degrees in just a month. Astronomers spotted this during a radio burst in 2025. It turns out that since 2023, the "beam" had been wandering within a 70-degree range, but the abrupt jump in 37 days set a record.