by Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Follow-up observations showed that the streak is more than 200,000 light-years long – about twice the width of the Milky Way – and is thought to be composed of compressed gas that is actively forming stars. The gas follows a black hole estimated to be 20 million times the mass of the Sun, moving away from its host galaxy at 5.6 million km/h, or about 4,500 times the speed of sound.
According to the researchers, the streak points right into the center of a galaxy where a supermassive black hole would normally sit.
“We found a thin line in a Hubble image that points to the center of a galaxy,” the study’s lead author said Pieter van Dokkum (opens in new tab), professor of physics and astronomy at Yale University, to Live Science. “Using the Keck telescope in Hawaii, we found that the line and the galaxy are connected. From a detailed analysis of the feature, we concluded that we are seeing a very massive black hole that was ejected from the galaxy, leaving a trail of gas and newly formed stars in its wake.”
Confirmation of the tail of an ejected black hole
Most, if not all, large galaxies harbor supermassive black holes at their centers. Active supermassive black holes often hurl jets of material at high speeds, which can be seen as streaks of light superficially similar to what the researchers have discovered. These are called astrophysical jets.
To determine that this is not what they observed, van Dokkum and the team examined this streak and found it showed none of the telltale signs of an astrophysical jet. While astrophysical jets weaken as they move away from their source of emission, the potential tail of a supermassive black hole actually gets stronger the farther it travels from its apparent galactic point of origin, the researchers say. Astrophysical jets fired from black holes also fan out from their source, while this trail appears to have remained linear.
The team concluded that the explanation that best fits the streak is a supermassive black hole darting through the gas surrounding its galaxy while compressing that gas enough to send in its wake the triggers star formation.
“If this is confirmed, it would be the first time we have unequivocal evidence that supermassive black holes can escape from galaxies,” said van Dokkum.
Black holes in motion
Once the runaway supermassive black hole is confirmed, the next question astronomers must answer is how such a monstrous object is ejected from its host galaxy.
“The most likely scenario that explains everything we’ve seen is a slingshot caused by a three-body interaction,” van Dokkum said. “When three bodies of similar mass interact gravitationally, the interaction does not result in a stable configuration, but usually results in the formation of a binary system and the ejection of the third body.”
This could mean that the runaway black hole was once part of a rare binary supermassive black hole, and a third supermassive black hole was introduced into this partnership during a galactic merger, ejecting one of its inhabitants.
Astronomers are unsure how common these massive outliers are.
“Ejected supermassive black holes have been predicted for 50 years, but none have been clearly seen,” said van Dokkum. “Most theorists believe there should be many out there.”
More observations with other telescopes are needed to find direct evidence of a black hole at the top of the mysterious streak, van Dokkum added.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
Astronomers have discovered a runaway supermassive black hole that appears to have been ejected from its host galaxy, hurtling through space with a chain of stars in tow.
This emerges from research by the team, which was published on the preprint server arXiv.org (opens in new tab) and accepted for publication in The Astrophysical Journal Letters, the discovery provides the first observational evidence that supermassive black holes can be ejected from their home galaxies to roam interstellar space.
The researchers spotted the outlier black hole as a bright streak of light as they observed the dwarf galaxy RCP 28, located about 7.5 billion light-years from Earth, with the Hubble Space Telescope.
