Biggest black hole jets ever seen are as long as 140 Milky Ways

Astronomers have spotted the biggest pair of black hole jets ever seen — at 23 million light-years in length, they are as long as 140 Milky Way galaxies laid end to end.

The enormous jet pair, nicknamed Porphyrion after a giant in Greek mythology, are gigantic beams of ionized matter that erupted from a black hole at close to light speed. Their origin is a massive black hole 7.5 billion light-years away from Earth, which they burst from with the power of trillions of stars.

The jets were discovered among 10,000 others in a survey by Europe's Low Frequency Array (LOFAR) radio telescope. By studying the tendrils of these colossal outflows, scientists hope to understand how they shaped the early cosmos into the form we see today. The researchers published their findings Sept. 17 in the journal Nature.

"This pair is not just the size of a solar system, or a Milky Way; we are talking about 140 Milky Way diameters in total," study lead author Martijn Oei, a postdoctoral scholar of observational Astronomy at Caltech, said in an email statement. "The Milky Way would be a little dot in these two giant eruptions."

Supermassive black holes typically sit at the centers of galaxies, sucking in matter from their surroundings before spitting it out at extreme speeds, creating a feedback process that shapes how galaxies evolve.

But scientists still don't fully understand how the cosmic engines and the jets they expel affect the galaxies around them.

Related: Monster black hole is starving its host galaxy to death, James Webb telescope reveals