Astronomers have discovered remarkably powerful X-ray jets emanating from two supermassive black holes that are so ancient they shine in the afterglow of the Big Bang.

“They are transforming the first light of the universe into high-energy jets,” said Jaya Maithil, a postdoctoral research fellow at the Harvard and Smithsonian Centre for Astrophysics. She spoke to reporters on June 9 at the 246th meeting of the American Astronomical Society in Anchorage, Alaska, reported Space.com.

Using data from Nasa’s Chandra X-Ray Observatory and the Karl G Jansky Very Large Array (VLA), Maithil and her team found that each jet spans an astonishing 300,000 light-years — nearly three times the diameter of our Milky Way galaxy. Each jet originates from an actively feeding supermassive black hole, known as a quasar, located about 11.6 billion and 11.7 billion light-years away.

The researchers observed these enormous structures as they existed when the universe was just 3 billion years old, during a time when galaxies and their central black holes were growing at a rapid pace.

“These quasars are like cosmic time capsules,” Maithil said. “If we understand them, we can understand how they were impacting the growth of their galaxy and the environment in which they resided.”

One of the newly discovered jets, from a quasar designated J1610+1811, is visible in the accompanying Chandra image. A slender, faint purple line extends from the quasar’s brilliant white core toward the upper right, terminating in a small bright blob. A second, dimmer jet appears to shoot in the opposite direction, downward and to the left.

“It’s like looking for candlelight in close vicinity to a flashlight that’s blazing toward us,” Maithil said.

What makes these jets particularly noteworthy is their visibility across billions of light-years. In a paper accepted for publication in The Astrophysical Journal, Maithil and her team suggested that the jets emit X-rays due to interactions with the cosmic microwave background (CMB)—the faint relic radiation from the Big Bang that remains after the universe cooled enough for starlight to travel freely, marking the end of the “cosmic dark ages.”