Scientists confirm another 44 black hole mergers detected by gravitational waves
Scientists have now confirmed that since the first detection of a gravitational wave five years ago they have detected another 44 black hole mergers in the same manner.
A global network of scientists has completed the first major analysis of gravitational wave data, providing exciting insights into some of the most exotic objects in the Universe. “We are announcing the discovery of 44 confirmed black hole mergers, which is a more than a four-fold increase in the number of previously known gravitational-wave signals,” says Shanika Galaudage from Australia’s Monash University, who was part of the research team.
…Their results are described in a trio of papers on the pre-print server arXiv. The first paper describes 39 new detections from the first half of the observing run, primarily of binary black hole systems. This brings the total number of gravitational wave events detected to 47, of which 44 are confidently double black holes, two are confidently double neutron stars, and one is still uncertain.
They think they are detecting more black hole mergers because they are heavier and thus emit bigger and more easily detected waves. They are also finding that the black hole mergers fall into two classes, two holes spinning in the same direction and two holes spinning in opposite or randomly different directions. The former formed together as a binary star system. The latter formed independently and somehow ended up linked up and merging.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Scientists have now confirmed that since the first detection of a gravitational wave five years ago they have detected another 44 black hole mergers in the same manner.
A global network of scientists has completed the first major analysis of gravitational wave data, providing exciting insights into some of the most exotic objects in the Universe. “We are announcing the discovery of 44 confirmed black hole mergers, which is a more than a four-fold increase in the number of previously known gravitational-wave signals,” says Shanika Galaudage from Australia’s Monash University, who was part of the research team.
…Their results are described in a trio of papers on the pre-print server arXiv. The first paper describes 39 new detections from the first half of the observing run, primarily of binary black hole systems. This brings the total number of gravitational wave events detected to 47, of which 44 are confidently double black holes, two are confidently double neutron stars, and one is still uncertain.
They think they are detecting more black hole mergers because they are heavier and thus emit bigger and more easily detected waves. They are also finding that the black hole mergers fall into two classes, two holes spinning in the same direction and two holes spinning in opposite or randomly different directions. The former formed together as a binary star system. The latter formed independently and somehow ended up linked up and merging.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
44 new discoveries now released. And 2 neutron star mergers, and determining the relative rotation of the merging partners. That’s pretty good work!
I heard decades ago about the ridiculous sensitivity that LIGO needs, and thought for myself that “This will never happen.” And ignored it. Then it happened! Lesson learned: When 1,000 published physicists work on the same project, do not assume that it won’t work! They probably don’t waste their time, other than probabilistically (an explanation of my own non-doing much that doesn’t work well with my slave owning girl friend, though, at least probably not.)
I like that quick paper that appeared as soon as the first gravity wave was detected. Predicting, using the sample of 1, that between 2 and 200 gravity waves will be detected by LIGO per year. And with about 50 delivered, that was a bloody good spot on forecast! My boss wouldn’t have appreciated such a forecast much, but it was evidently rigorous.
That’s a lot of black hole mergers. 44 in 5 years is around 8 per year. For a universe that is 13 billion years old, that is around 100 billion mergers over the life of the universe.
Edward: Actually, astronomers are pretty sure that black holes form approximately one per day, across the entire universe. That’s the rate of gamma ray bursts that has been tracked now for decades, and each burst is thought to be the signal of a black hole birth
Bob -One per day. Huh.
Wild speculation time – I wonder if “biological” modeling could be used to predict the occurrence of these based on estimated material available to create such black holes OR estimate the material based on the black hole birth rate. (x(n+1) = Rx(n)(1-x(n0))
Wild speculation I know
x(n0) is incorrect. Should be x(n)
@Edward
The machine is only turned on for some of the time. In between they polish the mirrors, reweight their balances, measure their strings, dust off their lenses, vacuum clean the tunnels, upgrade their software, convince the lumberjacks around to stop the jacking for a while, and whatever else is involved with maintaining such a strange machine.
I saw Kip Thorne in one of those Nobel prize interviews saying that he only casually looked at the detection illustrated on his screen as it popped up. Because the Thing was under maintenance then, and he assumed that it was a test signal, because it was so spot on and clear. Until a colleague rushed into his room and said that something wonderful has happened! And Kip Thorne has been working on this since the 1960s. “- Was that it?” He earlier gave name to the Thorne–Zytkow star, a neutron star that orbits inside of a red giant. A prediction then confirmed. And which proves that aliens do have strange 1950s scifi Hollywood names.
When the on-button is pressed, I think LIGO detects about 50 gravitational waves a year. Although they often release them by the batch as there’s some math to it in the overwhelming noise and scientists, unlike politicians, don’t want to make fools out of themselves when they open their mouths. If they don’t come from merging black holes, it will be the more exciting! Cosmic string fusion, eh?
Chris: The modeling would be fun, but utter scientific garbage (as most models are).