Astronomers have uncovered the first solid evidence that merger events between black holes can deliver a "kick" powerful enough to send a black hole spinning out of its galaxy.
The team, which included Vijay Varma, a physicist at Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Germany, examined gravitational-wave data from the merger event known as GW200129 collected by the LIGO detectors and their European counterpart, Virgo. Through that analysis, the scientists discovered that the black hole created in that collision and merger had been sent hurtling through space at 3 million mph (4.8 million kph) a finding described by one team member as "both surprising and shocking."
"When two black holes collide, they leave behind a more massive, remnant black hole. This process can impart a recoil 'kick' to the remnant black hole," Varma, lead author of a paper detailing the team's work, told Space.com.
Related: 8 ways we know that black holes really do exist
When black holes orbit each other, they emit gravitational waves essentially gravitational radiation that carry away energy and angular momentum as they ripple through the fabric of space. These emissions cause the orbit to shrink, leading to a collision and merger of the black holes.
If the black holes have unequal masses or spins, however, this leads to an asymmetry in the emission of gravitational waves, with them being primarily emitted in one direction. Because the basic laws of physics require that momentum has to be conserved, this asymmetry results in a large kick, causing the remnant black hole to recoil in the opposite direction.
"Black hole mergers also emit gravitational radiation, similar to astrophysical processes that emit electromagnetic radiation light," Varma continued.
These large kicks are expected when the merger's orbital plane precesses, or "wobbles." Orbital precession is observable as a small amplitude modification in the gravitational-wave signal. "This binary black hole system is also the first signal showing strong signs of orbital precession, whereby the orbital plane wobbles," co-author Scott Field, a mathematician at the University of Massachusetts Dartmouth, told Space.com.
Varma added that by analyzing gravitational radiation, astronomers and astrophysicists can learn about black-hole mergers. Additionally, because black holes are influential in the evolution of the galaxies, learning more about these processes could reveal how collections of stars like the Milky Way develop.
This is the first time astronomers have collected strong evidence that such a merger can eject the resulting black hole from its galaxy.
"Unlike previously observed black hole merger events, this is the first one to provide strong evidence for enormous recoil velocity. Large enough, in fact, for the remnant black hole to most likely escape from its host environment," Field said. "While we knew general relativity allowed for such extreme possibilities in principle, we did not know if the universe would produce them. The final black hole's speed is sufficiently large that it most probably exceeds the escape velocity of its host environment."
Field added that this result will have important implications for binary black hole formation scenarios, too. This is because supermassive black holes, like Sagittarius A* (Sgr A*) at the heart of the Milky Way, form through a series of collisions that scientists call hierarchical mergers. Black holes kicked from a galaxy can't partake in this process.
The discovery of mergers lopsided enough to give black holes a powerful kick is now possible thanks to technology that allows for more precise detections of gravitational waves.
"Black hole mergers don't emit any light, so gravitational waves are the only way to observe and learn about them. We would not know about this ejected, rogue black hole without gravitational wave observatories," Field added.
Scientists aren't precisely sure where the gravitational wave event GW200129 originated, so Field points out that the team can't completely sure the black hole was ejected from its galaxy, but this is the probable outcome of it moving at such extreme speeds, according to the researchers.
"If that is indeed the case, it is now roaming around the universe by itself as a rogue black hole," Varma said.
The merger that occurred here may be a miniature version of an even more dramatic event, he noted. "A similar phenomenon happens when supermassive black holes merge, which can happen after a galactic merger," Varma said. "The final supermassive black hole can get displaced from the center of the merged galaxy, or even ejected from it, leaving behind a galaxy without a central black hole."
Although existing gravitational-wave detectors are not quite powerful enough to observe supermassive black hole mergers, the authors added that future space-based detectors like the proposed Laser Interferometer Space Antenna (LISA) mission, might be able to.
"Gravitational-wave astronomy has delivered many high-impact, truly remarkable discoveries over the past five or so years," Field said. "Before the first detection of gravitational waves, the mantra of our field had been that gravitational waves will open a new window on the universe. And this has proven to be true with each and every new LIGO observing run."
The research is described in a paper (opens in new tab) published May 12 in the journal Physical Review Letters.
You can follow Rob Lea on Twitter at @sciencef1rst. Follow us on Twitter @Spacedotcom (opens in new tab) and on Facebook (opens in new tab).
Read more:
A black hole formed by a lopsided merger may have gone rogue - Space.com
- Astronomy clubs want to help you enjoy the eclipse safely - NPR - March 16th, 2024 [March 16th, 2024]
- You Can See a Rare, Bright Comet This Month. Will It Be Visible During the Solar Eclipse? - Smithsonian Magazine - March 16th, 2024 [March 16th, 2024]
- Solar Eclipse Path Map Shows States Where Sun Will Be Blocked Out - Newsweek - March 16th, 2024 [March 16th, 2024]
- Deep-space astronomy sensor peers into the heart of an atom - Space.com - March 16th, 2024 [March 16th, 2024]
- Physics and Astronomy Colloquium - Professor Paul Cassak; Department of Physics and Astronomy, West Virginia ... - The University of Iowa - March 16th, 2024 [March 16th, 2024]
- United Nations prioritizes discussion of Dark and Quiet Skies - Astrobites - March 16th, 2024 [March 16th, 2024]
- The burning acid behind ant stings was spotted around two stars - WAPT Jackson - March 16th, 2024 [March 16th, 2024]
- The oddities known as Centaurs may sprout their tales after jumping to new orbits - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Pair of astronomy brothers to host eclipse viewing event - KAIT - March 16th, 2024 [March 16th, 2024]
- How to watch the solar eclipse online - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- How does a black hole get to the center of a galaxy, and does the galaxy revolve around it? - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- The eclipse gives astronomy clubs an opportunity to shine - Voice Of Alexandria - March 16th, 2024 [March 16th, 2024]
- AI 'for all': How access to new models is advancing academic research, from astronomy to education - Source - Microsoft - March 16th, 2024 [March 16th, 2024]
- KU Department of Physics & Astronomy professor receives prestigious NSF award for black hole research - Salina Post - March 16th, 2024 [March 16th, 2024]
- Inspect impressive Mare Imbrium Astronomy Now - Astronomy Now Online - March 16th, 2024 [March 16th, 2024]
- The Sky This Week from March 15 to 22: A conjunction of Venus and Saturn - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Pons-Brooks and M31 - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- The slightly weird mathematical coincidence behind an eclipse - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- APOD: 2024 March 17 NGC 7714: Starburst after Galaxy Collision - Astronomy Picture of the Day - March 16th, 2024 [March 16th, 2024]
- How to Safely View the Eclipse National Radio Astronomy Observatory - National Radio Astronomy Observatory - March 16th, 2024 [March 16th, 2024]
- NOIRLab releases jaw-dropping images, video of remnants from massive star explosion | Astronomy.com - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- JWST spots oceans' worth of water evaporating from a distant disk - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- Radiation is vaporizing a young star's disk in the Orion Nebula - Astronomy Magazine - March 16th, 2024 [March 16th, 2024]
- APOD: 2024 March 12 A Galaxy Shaped Rocket Exhaust Spiral - Astronomy Picture of the Day - March 16th, 2024 [March 16th, 2024]
- Best laptops for astronomers and astrophotographers in 2024 - Space.com - March 16th, 2024 [March 16th, 2024]
- Why astronomers are worried about 2 major telescopes right now - Space.com - March 16th, 2024 [March 16th, 2024]
- The People Behind Webb | Webb - WebbTelescope.org - March 16th, 2024 [March 16th, 2024]
- X-ray image of universe reveals almost 1 million high-energy objects: 'These are mind-blowing numbers' - Space.com - February 1st, 2024 [February 1st, 2024]
- Galaxy named 'Nube' is almost invisible, baffling astronomers Earth.com - Earth.com - February 1st, 2024 [February 1st, 2024]
- Giant Star Seen 150 Days Before it Exploded as a Supernova - Universe Today - February 1st, 2024 [February 1st, 2024]
- UH astronomer named to prominent national astronomical society | University of Hawaii System News - University of Hawaii - February 1st, 2024 [February 1st, 2024]
- The Art of SeeingStates of Astronomy - Announcements - E-Flux - February 1st, 2024 [February 1st, 2024]
- Pluto isn't really a planet, but it might be Arizona's official state planet - Arizona Mirror - February 1st, 2024 [February 1st, 2024]
- Did You Know? Stars Near and Far Reveal Their Secrets to CSUN Scientists - California State University, Northridge - February 1st, 2024 [February 1st, 2024]
- Top 10 space stories of 2023 - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- How we found the Milky Way's bar: This Week in Astronomy with Dave Eicher - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- The best telescope to use with a smartphone - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- JWST releases 19 awe-inspiring images of spiral galaxies - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- Learning Shines Brightly at SuperKnova National Radio Astronomy Observatory - National Radio Astronomy Observatory - February 1st, 2024 [February 1st, 2024]
- The Crafoord Prize 2024 goes to three ERC grantees for their pioneering contributions to astronomy and mathematics ... - European Research Council - February 1st, 2024 [February 1st, 2024]
- The Moon's south pole is likely not the safest place for manned missions - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- The moon could be perfect for cutting-edge telescopes but not if we don't protect it - Space.com - February 1st, 2024 [February 1st, 2024]
- February Astronomy: Spot the Milky Way and the Zodiacal Light While the Skies Are Darkest - Coachella Valley Independent - February 1st, 2024 [February 1st, 2024]
- You can stream an asteroid whizzing past Earth this weekend - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- Chinese Astronomy at the Royal Observatory | Royal Observatory | Things to do in London - Time Out London - February 1st, 2024 [February 1st, 2024]
- Astronomers in Chile to scour universe with car-sized mega camera - - February 1st, 2024 [February 1st, 2024]
- Dark Matter Might Help Explain How Supermassive Black Holes Can Merge - Universe Today - February 1st, 2024 [February 1st, 2024]
- How far away is the sun? They went on a perilous journey to find out. - National Geographic - February 1st, 2024 [February 1st, 2024]
- Scientists spotted an asteroid hours before it burned up over Germany - Astronomy Magazine - February 1st, 2024 [February 1st, 2024]
- XRISM Unveils the Invisible: A New Era in X-Ray Astronomy - SciTechDaily - January 10th, 2024 [January 10th, 2024]
- New Astronomy Finding Uncovers the Mystery of Star Formation at the Edge of Galaxies - SBU News - Stony Brook News - January 10th, 2024 [January 10th, 2024]
- The Future Of Astronomy Lies In Artificial Intelligence - Forbes - January 10th, 2024 [January 10th, 2024]
- The 'Super Bowl of Astronomy' begins next week in New Orleans - Space.com - January 10th, 2024 [January 10th, 2024]
- Scientific American proposes policing the language of astronomy to make it beautiful and elegant, as well as ... - Why Evolution Is True - January 10th, 2024 [January 10th, 2024]
- 'Blob-like' home of farthest-known fast radio burst is collection of seven galaxies - Northwestern Now - January 10th, 2024 [January 10th, 2024]
- Astronomers revealed mysterious star formation by hearts of molecular clouds - Tech Explorist - January 10th, 2024 [January 10th, 2024]
- Spectroscopic sizing of interstellar icy grains with JWST - Nature.com - January 10th, 2024 [January 10th, 2024]
- Kip Thorne and the mind-bending science of Interstellar | Astronomy.com - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Here There Be DRAGNs National Radio Astronomy Observatory - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- Unistellar's latest smart telescopes take the hassle out of backyard astronomy - Engadget - January 10th, 2024 [January 10th, 2024]
- 20 of the best places to view the 2024 total solar eclipse - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Northern Arizona astronomy: How old is our third generation sun? - Grand Canyon News - January 10th, 2024 [January 10th, 2024]
- Evidence builds that Kamo'oalewa is a chunk of the Moon accompanying Earth - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- The Sky This Week from January 5 to 12: Visitors to the Scorpion - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- AAS 243 NRAO Press Announcement - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- Your guide to the sky in 2024 - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- The best binoculars for astronomy in 2024 - Popular Science - January 10th, 2024 [January 10th, 2024]
- Are we visible to alien astronomers? This study makes the case - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Mystery of Star Formation Revealed by Hearts of Molecular Clouds - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- Astronomers Solve the Mystery of Giant Radio Circles - AZoQuantum - January 10th, 2024 [January 10th, 2024]
- Early Evolution of Planetary Disk Structures Seen for the First Time - National Radio Astronomy Observatory - January 10th, 2024 [January 10th, 2024]
- XRISM's Revolutionary Insights into X-Ray Astronomy - AZoQuantum - January 10th, 2024 [January 10th, 2024]
- Vatican's chief astronomer talks about stars, beauty, truth - Aleteia - January 10th, 2024 [January 10th, 2024]
- Explore the cosmos in EAC Payson Campus astronomy workshops - Payson Roundup - January 10th, 2024 [January 10th, 2024]
- Neptune is more of a greenish blue than is commonly depicted - NPR - January 10th, 2024 [January 10th, 2024]
- First Yale Gravitational Wave Symposium sparks research innovation | Department of Physics - Yale University - January 10th, 2024 [January 10th, 2024]
- The best expensive telescopes for those ready to splurge - Astronomy Magazine - January 10th, 2024 [January 10th, 2024]
- Dinosaurs and a touch of astronomy | Education | paysonroundup.com - Payson Roundup - January 10th, 2024 [January 10th, 2024]
- Astronomical Illusions: New Images Reveal What Neptune and Uranus Really Look Like - SciTechDaily - January 10th, 2024 [January 10th, 2024]
- Book Review: Things That Go Bump in the Universe, by C. Rene James - The New York Times - December 16th, 2023 [December 16th, 2023]