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New submitter nichogenius writes: The latest observation run of LIGO and VIRGO only started April 1st, but has already observed another black hole merger. The LIGO detectors have been offline since the 25th of August, 2017 for a series of upgrades. The latest observational run is the first run where gravitational wave events are being publicly announced as they happen rather than being announced weeks or months later. Few details of the merger are available at this time, but there is some information available on LIGO's twitter and raw details can be obtained from LIGO's event database page.

Gravitational detection events are being publicly broadcast using NASA's VOEvent system. If you know a bit of python, you can setup your own VOEvent client using the pygcn module with example code available in this tutorial.

New submitter nichogenius writes: The latest observation run of LIGO and VIRGO only started April 1st, but has already observed another black hole merger. The LIGO detectors have been offline since the 25th of August, 2017 for a series of upgrades. The latest observational run is the first run where gravitational wave events are being publicly announced as they happen rather than being announced weeks or months later. Few details of the merger are available at this time, but there is some information available on LIGO's twitter and raw details can be obtained from LIGO's event database page.

Gravitational detection events are being publicly broadcast using NASA's VOEvent system. If you know a bit of python, you can setup your own VOEvent client using the pygcn module with example code available in this tutorial.

An anonymous reader quotes a report from The Guardian: Astronomers have made a new detection of gravitational waves and for the first time have been able to trace the shape of ripples sent through spacetime when black holes collide. The announcement, made at a meeting of the G7 science ministers in Turin, marks the fourth cataclysmic black-hole merger that astronomers have spotted using Ligo, the Laser Interferometer Gravitational-Wave Observatory. The latest detection is the first to have also been picked up by the Virgo detector, located near Pisa, Italy, providing a new layer of detail on the three dimensional pattern of warping that occurs during some of the most violent and energetic events in the universe.

A tiny wobble in the signal, picked up by Ligo's twin instruments and the Virgo detector on 14 August, could be traced back to the final moments of the merger of two black holes about 1.8 billion years ago. The black holes, with masses about 31 and 25 times the mass of the sun, combined to produce a newly spinning black hole with about 53 times the mass of the sun. The remaining three solar masses were converted into pure energy that spilled out as deformations that spread outwards across spacetime like ripples across a pond. Detecting these tiny distortions has required detectors sensitive enough to measuring a discrepancy of just one thousandth of the diameter of an atomic nucleus across a 4km laser beam. A paper about the latest discovery has been accepted for publication in the journal Physical Review Letters.

"Scientists possibly detected an entirely different type of gravitational wave [source]," writes schwit1. "Gossip over potential detection of colliding neutron stars has astronomers in a tizzy," reports Nature: Astrophysicists may have detected gravitational waves last week from the collision of two neutron stars in a distant galaxy -- and telescopes trained on the same region might also have spotted the event. Rumours to that effect are spreading fast online, much to researchers' excitement. Such a detection could mark a new era of astronomy: one in which phenomena are both seen by conventional telescopes and 'heard' as vibrations in the fabric of space-time. "It would be an incredible advance in our understanding," says Stuart Shapiro, an astrophysicist at the University of Illinois at Urbana-Champaign...

The Laser Interferometer Gravitational-Wave Observatory (LIGO) in Louisiana and Washington state has three times detected gravitational waves -- ripples in the fabric of space-time -- emerging from colliding black holes. But scientists have been hoping to detect ripples from another cosmic cataclysm, such as the merger of neutron stars, remnants of large stars that exploded but were not massive enough to collapse into a black hole.
One astronomer tweeted last week that "merging neutron-neutron star is the initial call," while Nature adds that the same rumor had already been circulating privately, according to "some astronomers who do not want to be identified."

Friday Ligo announced cautiously that "We are working hard to assure that the candidates are valid gravitational-wave events, and it will require time to establish the level of confidence needed to bring any results to the scientific community and the greater public. We will let you know as soon we have information ready to share."

StartsWithABang writes: When we look out into the Universe, we normally gain information about it by gathering light of various wavelengths. However, there are other possibilities for astronomy, including by looking for the neutrinos emitted by astrophysical sources - first detected in the supernova explosion of 1987 - and in the gravitational waves emitted by accelerating masses. These ripples in the fabric of space were theorized back in the early days of Einstein's General Relativity, and experiments to detect them have been ongoing since the 1960s. However, in September of 2015, Advanced LIGO came online, and it was the first gravitational wave observatory that was expected to detect a real gravitational wave signal. The press conference on Thursday is where the collaboration will make their official announcement, and in the meantime, here's an explainer of what gravitational waves are, what Advanced LIGO can teach us, and how.

b30w0lf writes "Gravitational wave detection — i.e. the detection of propagating ripples in spacetime — is a hot subject these days, with ground-based interferometer experiments like LIGO active, and hopes for a space interferometer like LISA. However, physicist Freeman Dyson proposed back in 1969 that the earth itself could be used as a gravitational wave detector. The idea is behind the approach is that gravitational waves impact the earth's crust, causing potentially detectable seismic waves. Using Dyson's approach, Physicists at Harvard and NINP, Florence were able to put an upper limit on the intensity of gravitational background radiation based on a year of observational seismic data (abstract, full pre-print). The upper limit they found improved currently laboratory upper limits by 9 orders of magnitude."