Science
Related: About this forumHere’s What Happens When Two Black Holes Collide
Last September, a small chirp rattled a pair of L-shaped antennas for the first time. Thats the sound you hear when theres a ripple in the fabric of space and time a gravitational wave. The wave is caused by two black holes colliding, circling each other at half the speed of sound, tugging at the space and time around them.
This December, scientists heard the chirp again, confirming Albert Einsteins Theory of Relativity for the second time in recorded history.
David Reitze played a key role in the discovery. Hes the executive director of the Laser Interferometer Gravitational-Wave Observatory (LIGO), which operates the antennas in Louisiana and Washington state that picked up the waves.
On a fundamental scale it changes the way we look at the universe, he says. So its a new kind of astronomy. And I think everybody can get excited about that.
Read more: http://www.texasstandard.org/stories/heres-what-happens-when-two-black-holes-collide/
DetlefK
(16,423 posts)Bernardo de La Paz
(48,870 posts)There is so much gravitational noise that only big events punch through. And the distances are so far that the signal dissipates and weakens by time we get it. Then gravity is fundamentally so weak that it takes huge detectors.
Helen Borg
(3,963 posts)krispos42
(49,445 posts)Or the speed of light?
TexasTowelie
(111,643 posts)Cosmic things, you know.
Bernardo de La Paz
(48,870 posts)... for the black hole movement, approximately 350 miles per hour.
The gravity waves travel at the speed of light, I'm pretty sure.
caraher
(6,277 posts)The orbital period in those final moments is measured in seconds... 350 MPH is basically stationary, when you look at the size of the orbits of these bodies about their center of mass.
Plus 700 MPH is the speed of sound, in air, at sea level. The speed of sound depends on the physical medium, and there is no physical relevance of the speed of sound in air (basically nitrogen) at standard temperature and pressure, for black holes moving out in space.
The whole article is badly written, so I forgive anyone confused by it... the December detection is the second direct gravitational wave detection. That is not at all, even remotely, the same as "confirming Albert Einsteins Theory of Relativity for the second time in recorded history." The author probably couldn't even tell you *which* theory of relativity this would confirm (general relativity). Even had the author said "second confirmation of Einstein's prediction of gravitational waves" most knowledgeable physicists would consider that dead wrong; Taylor and Hulse received a Nobel for observations performed decades ago that were pretty much universally taken to confirm gravitational waves. The difference is they didn't detect the waves themselves, they observed the waves indirectly by looking at energy loss in fast-rotating binary systems.
Gruenemann
(975 posts)Text reads "This December", which would certainly be a disturbance in the space-time continuum. Audio implies it was this September.
Thanks for explaining the "speed of sound" effup.
caraher
(6,277 posts)I have a former student on the LIGO team and I know they saw two events in fall 2015, one that they wrote up in the big paper and a second one. I don't remember whether it was in September or December.
But I'm pretty sure December 2016 is wrong!
Beartracks
(12,774 posts)The author of the article wrote it wrong.
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msanthrope
(37,549 posts)burrowowl
(17,618 posts)Bozvotros
(782 posts)cpwm17
(3,829 posts)Kind of Blue
(8,709 posts)Spitfire of ATJ
(32,723 posts)x2.
Or is it ²?
closeupready
(29,503 posts)it stands to reason that black holes are colliding all over the place, all the time, right?
I mean, yet another set of data showing how absolutely mindblowingly MASSIVE the universe is.
AlbertCat
(17,505 posts)The universe is very big and very old and amazing coincidences happen all the time.
ScienceIsGood
(314 posts)TexasTowelie
(111,643 posts)and welcome to DU!
I think that you will find a lot of interesting articles in the Science Group so please enjoy.