China's Einstein Probe discovers EP240305a, a category-defying cosmic transient
China's Einstein Probe just found something wild in space, a cosmic event called EP240305a that doesn't fit any known category.
Spotted on March 5, 2024, it flashed two bursts of X-rays with a quiet gap in between, then faded out over days, and left radio signals hanging around for weeks.
The discovery got published in June 2026 and has scientists scratching their heads.
Event resembles GRBs but lacks gamma-rays
This event looks a lot like gamma-ray bursts (GRBs), thanks to its double X-ray flare and expanding jet that showed up as radio waves.
But here's the twist: it didn't have the usual gamma-ray flash GRBs are famous for. So researchers are calling it a possible "gamma-ray-dark GRB-like transient."
Attempts to match it with other cosmic events came up empty.
Scientists suspect off-axis or obscured jet
Scientists think the missing gamma rays could be because of an off-angle jet or maybe a jet blocked by surrounding matter.
The Einstein Probe's sensitive tech might help spot more of these faint explosions that older surveys missed, opening up new ways to understand our universe.