Astronomers have found the largest pair of black hole jets on record, with the 6.3 billion-year-old megastructure shooting out the power of trillions of suns at the heart of a remote galaxy.

Porphyrion, nicknamed after a mythological giant, can be found billions of light years away and was located using observatories and radio telescopes in Europe, India, Arizona and Hawaii.

Martijn Oei, a Caltech postdoctoral scholar and lead author of a new Nature paper, said the pair are bigger than the entire solar system.

“We are talking about 140 Milky Way diameters in total,” he said.

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You won’t believe this discovery! 🚀 Astronomers just found the largest black hole jet system EVER, and it’s a monster! 🌌 Meet Porphyrion—a structure 23 million light-years long, created by a supermassive black hole. 💥 Paper details: Oei, M.S.S.L., Hardcastle, M.J., Timmerman, R. et al. Black hole jets on the scale of the cosmic web. Nature 633, 537–541 (2024). Link: https://rdcu.be/dUHl9 BlackHole Astronomy LOFAR SpaceDiscovery Galaxies

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“The Milky Way would be a little dot in these two giant eruptions.”

A black hole jet is caused by violent and energetic events around a black hole, which itself is the remains of a super-massive star that has collapsed, that can span across galaxies and space.

Discovery

Oei said that he and his colleagues were originally studying the cosmic web of wispy filaments that crisscrosses the space between galaxies in 2018 using Europe’s Low-Frequency Array Telescope (LOFAR), but noticed several strikingly long jet systems.

“When we first found the giant jets, we were quite surprised,” Oei said.

“We had no idea that there were this many.”

The LOFAR array in the Netherlands. Photo: ASTRON

The team then used a telescope in India and Arizona to pinpoint the original home of the jets, locating it in a large galaxy that is about 10 times bigger than the Milky Way.

George Djorgovski, co-author and professor of astronomy at Caltech University, said astronomers believe that galaxies and their central black holes co-evolve.

“One key aspect of this is that jets can spread huge amounts of energy that affect the growth of their host galaxies and other galaxies near them,” he said.

“This discovery shows that their effects can extend much farther out than we thought.”

Using additional data from an observatory in Hawaii, Oil said that it showed that Porphyrion is 7.5 billion light years away.

“Up until now, these giant jet systems appeared to be a phenomenon of the recent universe,” he said.

“If distant jets like these can reach the scale of the cosmic web, then every place in the universe may have been affected by black hole activity.”

Future studies

Questions still remain about how the jets can extend beyond their own galaxy without destabilising and disappearing, but the researchers want to better understand how they impact surrounding galaxies, planets and space itself.

“We may be looking at the tip of the iceberg,” Oei said.

“Our LOFAR survey only covered 15 per cent of the sky. And most of these giant jets are likely difficult to spot, so we believe there are many more of these behemoths out there.”

He said he was particularly interested in the extent to which the black hole jets spread magnetism.

“The magnetism on our planet allows life to thrive, so we want to understand how it came to be,” Oei said.

“We know magnetism pervades the cosmic web, then makes its way into galaxies and stars, and eventually to planets, but the question is: Where does it start?”

Black holes have long been a focus of scientists and science fiction writers alike.