Explanation: Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitationalwaves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown. A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity's understanding of gravity and basic physics. It is also the most direct detection of black holes ever. The featured illustration depicts the two merging black holes with the signal strength of the two detectors over 0.3 seconds superimposed across the bottom. Expected future detections by Advanced LIGO and other gravitational wave detectors may not only confirm the spectacular nature of this measurement but hold tremendous promise of giving humanity a new way to see and explore our universe.
A new and exciting APOD will appear here today at 11:00 am Eastern Time (USA) after the LIGO press conference in Washington, DC has begun.
Oh such a tease! Looking forward to seeing it.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 5:43 am
by unknown unknowns
Finally, some real videos from Roswell? Thank you, Special Agent Moody, you finally delivered.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 6:09 am
by BMAONE23
No no no, it was special agents Fox Mulder and Dana Scully
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 6:46 am
by ShaileshS
Have North Koreans taken over the APOD website ? I'm guessing they are going to show us first live streaming data/pictures/videos from their satellite at 11am EST on Thursday ?
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 7:46 am
by Guest
Could it really be??? The Aliens have finally brought back Elvis???
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 10:25 am
by phlloydl
Why is it that Americans assume all the world understands their time zones? This is an astronomy-related web page and astronomers work in UT. So what is "11:00 am Eastern Tome" in UT, please?
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 11:11 am
by geckzilla
Oh, good luck with this. You are gonna have a million angry APODers on your butt if there aren't any gravitational waves. Haha.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 11:25 am
by RedFishBlueFish
phlloydl wrote:Why is it that Americans assume all the world understands their time zones? This is an astronomy-related web page and astronomers work in UT. So what is "11:00 am Eastern Tome" in UT, please?
February, 11 2016 16:00:00 (Thursday) at UTC 0
As EST is UTC-5
One's main concern is that, based upon experience, change to a website seems rarely to be favourable but generally results in loss of function, loss of legibility and loss of actual informational content with a concomitant paradoxical increase in required bandwidth and difficulty in site navigation.
One can but hope this will not be the case with APOD.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 12:14 pm
by Cousin Ricky
Can't they just compress space-time and get us the news now?
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 12:52 pm
by neufer
Cousin Ricky wrote:
Can't they just compress space-time and get us the news now?
phlloydl wrote:So what is "11:00 am Eastern Tome" in UT, please?
Glad you asked... 11:00 am Eastern Time is 9:00 am in Utah.
Rob
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 2:05 pm
by madtom1999
rstevenson wrote:
phlloydl wrote:So what is "11:00 am Eastern Tome" in UT, please?
Glad you asked... 11:00 am Eastern Time is 9:00 am in Utah.
1856
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 2:37 pm
by Galaxian
phlloydl wrote:Why is it that Americans assume all the world understands their time zones?
For the same reason USAliens (Not "Americans", as Mexicans and Canadians and South Americans all recognise that different countries with different customs exist) think we all worship Disney's rodent, eat hamburgers all day, are fascinated by the handball game they call "football", are obsessed with their version of rounders and are mesmerised by their ten-year long election processes. USAliens think Europe is a small town in Idaho., right next to Lorrrndon.
This is an astronomy-related web page and astronomers work in UT. So what is "11:00 am Eastern Tome" in UT, please?
According to http://www.worldtimebuddy.com/est-to-gmt-converter (a site no-one at NASA or JPL will ever see because it mentions "gmt", which is Un-American) 1100 EST is 1600 GMT, or roughly 1600 UTC, give or take a few seconds.
The APoD team could have looked that up but they, of course, don't know that there is a "rest of the world" so they don't bother.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 2:42 pm
by tomatoherd
I find that all these grand announcements are usually anti-climatic. I get more thrill seeing all four Galilean moons at once in binoculars. (But I'm easy pleased.)
I know the difference between theoretical and experimental science. But the gap is largest in physics - ginormous. And so would some mind more poetic than mine please comment on the picture of Einstein with his pencil (or chalk) and subsequent somewhat lesser minds with their billions-dollar Hadrons and LIGOs? But I don't need a lecture: I DO believe in experimental confirmation of theory. And am waiting for same on dark matter....
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 2:59 pm
by owlice
Galaxian wrote:
phlloydl wrote:Why is it that Americans assume all the world understands their time zones?
For the same reason USAliens (Not "Americans", as Mexicans and Canadians and South Americans all recognise that different countries with different customs exist) think we all worship Disney's rodent, eat hamburgers all day, are fascinated by the handball game they call "football", are obsessed with their version of rounders and are mesmerised by their ten-year long election processes. USAliens think Europe is a small town in Idaho., right next to Lorrrndon.
This is an astronomy-related web page and astronomers work in UT. So what is "11:00 am Eastern Tome" in UT, please?
According to http://www.worldtimebuddy.com/est-to-gmt-converter (a site no-one at NASA or JPL will ever see because it mentions "gmt", which is Un-American) 1100 EST is 1600 GMT, or roughly 1600 UTC, give or take a few seconds.
The APoD team could have looked that up but they, of course, don't know that there is a "rest of the world" so they don't bother.
I'm an American, and assumed that those not in the US are smart enough to make the adjustments necessary to translate units/time zones/etc. on a US-hosted web site to their own units/time zones/etc., just as I translate units/time zones/etc. on Swiss/UK/other non-US-hosted sites to units/time zones/etc. meaningful to me.
But maybe my assumption is as wrong as Galaxian's assumptions are about US residents.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 3:16 pm
by Chris Peterson
Galaxian wrote:According to http://www.worldtimebuddy.com/est-to-gmt-converter (a site no-one at NASA or JPL will ever see because it mentions "gmt", which is Un-American) 1100 EST is 1600 GMT, or roughly 1600 UTC, give or take a few seconds.
That's because there's really no such thing as GMT. Unlike Eastern Time, which is an internationally standardized time zone, GMT is just an informally recognized designation.
As long as a time is given using a standardized time zone, anybody with Internet access should be able to trivially convert it to their local time.
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 3:22 pm
by Chris Peterson
They'll be streaming the press conference on Caltech's home page, but there's already a video posted there that seems to be jumping the gun and announcing what they found.
<In 1981, Kip S. Thorne and Jeremiah P. Ostriker made a bet on the detection of Gravitational Waves:"... Therefore they agree to wager one case of good red wine (JPO to supply French wine, KST to supply California) on the detection of extraterrestrial gravitational waves before the next Millennium (January 1, 2000). KST wins the wager if at least two experimental groups observe phenomena which they agree are gravitational waves. If not, JPO wins."
Unfortunately, Kip Thorne has lost.>>
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 3:36 pm
by CHN Martok
Sighhh, quite happy with APOD as it is. New and exciting, well I dont need new and exciting, what I need and want is the site to be as it always has been. A amazing site to wake up to and the awe inspiring images that have graced these pages over the years. Screw that up and I will be a very unhappy American mkay....
Re: APOD: APOD Place Holder (2016 Feb 11)
Posted: Thu Feb 11, 2016 4:05 pm
by Abe Mikado
phlloydl wrote:Why is it that Americans assume all the world understands their time zones? This is an astronomy-related web page and astronomers work in UT. So what is "11:00 am Eastern Tome" in UT, please?
1600
Re: APOD: LIGO Detects Gravitational Waves (2016 Feb 11)
Re: APOD: LIGO Detects Gravitational Waves (2016 Feb 11)
Posted: Thu Feb 11, 2016 4:34 pm
by Galaxian
Explanation: Gravitational radiation has been directly detected.
That is neither new nor exciting.
Confirming the flightpath of light from stars was being bent by Sol's gravity well was new and exciting but that was about a century ago and nothing new has come out of Relativity since.
Finding that gravitational radiation was a myth, a phantom of the mathematics, and falsifying part of GR would have been new and exciting. It would have resulted in all sorts of new physics.
"We finally caught a gravity wave." isn't news. It's just the result of hard work and good engineering.
Yes, the engineers should celebrate the fine work they've done but this doesn't advance Science one bit.
Maybe, when Amazon sells gravity telescopes for amateurs at less than a hundred quid this event will be seen as the start of something but today it's just yet one more in a long, long, line of confirmations of GR.
And those are boring.
New physics would have been cool.
Oh, and Chris, GMT was an internationally recognised standard before your colony had the population of Tonga.
Re: APOD: LIGO Detects Gravitational Waves (2016 Feb 11)
Posted: Thu Feb 11, 2016 4:40 pm
by Ians
Shouldn't "Merger" be "coalescence"?
Re: APOD: LIGO Detects Gravitational Waves (2016 Feb 11)
Posted: Thu Feb 11, 2016 4:51 pm
by bystander
Gravitational Waves Detected 100 Years After Einstein's Prediction
LIGO | NSF | Caltech | MIT | 2016 Feb 11
LIGO Opens New Window on the Universe with Observation of Gravitational Waves from Colliding Black Holes
For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at the earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein’s 1915 general theory of relativity and opens an unprecedented new window onto the cosmos.
Gravitational waves carry information about their dramatic origins and about the nature of gravity that cannot otherwise be obtained. Physicists have concluded that the detected gravitational waves were produced during the final fraction of a second of the merger of two black holes to produce a single, more massive spinning black hole. This collision of two black holes had been predicted but never observed.
The gravitational waves were detected on September 14, 2015 at 5:51 a.m. Eastern Daylight Time (09:51 UTC) by both of the twin Laser Interferometer Gravitational-wave Observatory (LIGO) detectors, located in Livingston, Louisiana, and Hanford, Washington, USA. The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. The discovery, accepted for publication in the journal Physical Review Letters, was made by the LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the Virgo Collaboration using data from the two LIGO detectors.
Based on the observed signals, LIGO scientists estimate that the black holes for this event were about 29 and 36 times the mass of the sun, and the event took place 1.3 billion years ago. About 3 times the mass of the sun was converted into gravitational waves in a fraction of a second—with a peak power output about 50 times that of the whole visible universe. By looking at the time of arrival of the signals—the detector in Livingston recorded the event 7 milliseconds before the detector in Hanford—scientists can say that the source was located in the Southern Hemisphere. ...
LIGO Detects Gravitational Waves from Merging Black Holes
