01/12/2026
⚫ A supermassive black hole has been caught fleeing its home galaxy at over 2 million mph—and it's leaving a cosmic trail of stars in its wake.
Astronomers using the James Webb Space Telescope have confirmed the first runaway supermassive black hole, a cosmic behemoth 10 million times the mass of our Sun racing through space at 2.2 million mph (1,000 kilometers per second). This makes it one of the fastest-moving objects ever detected, traveling at roughly 3,000 times the speed of sound. The discovery was led by Pieter van Dokkum at Yale University and marks a milestone in observing phenomena long predicted by theory but never confirmed.
The black hole was initially spotted by the Hubble Space Telescope in 2023 as a mysterious streak extending 200,000 light-years from its host galaxy. JWST's NIRSpec instrument revealed the smoking gun: a dramatic bow shock at the tip of this feature, with gas velocity differences of 600 kilometers per second across just 1,000 light-years. This supersonic shock wave, pushing matter sideways at hundreds of kilometers per second, definitively proved the black hole's breakneck speed and direction.
Behind the black hole stretches a 200,000 light-year tail where shocked gas has triggered star formation, creating approximately 100 million solar masses worth of new stars. This unprecedented mode of star formation occurs far from any galaxy—essentially in empty space—as the runaway plows through intergalactic gas.
The most likely origin story involves two galaxies colliding, their central supermassive black holes merging and releasing powerful gravitational waves that kicked the newly formed black hole into space. Such cosmic violence requires enormous forces, yet simulations have long predicted these dramatic ejections should occur.
Future missions like the Nancy Grace Roman Space Telescope could reveal more of these galactic runaways lurking in deep space.
📄 RESEARCH PAPER
📌 Pieter van Dokkum et al, "JWST Confirmation of a Runaway Supermassive Black Hole via its Supersonic Bow Shock", The Astrophysical Journal Letters (2025)