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Explanation: Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsars in a way that indicates that they are caused by GWs. This GW background is likely due to hundreds of thousands or even millions of supermassive black hole binaries. Teams in Europe, Asia and Australia have also independently reported their results today. Previously, the LIGO and Virgo detectors have detected higher-frequency GWs from the merging...

Gravitational wave scientists from The University of Western Australia have led the development of a new laser mode sensor with unprecedented precision that will be used to probe the interiors of neutron stars and test fundamental limits of general relativity. Research Associate from UWA's Centre of Excellence for Gravitational Wave Discovery (OzGrav-UWA) Dr. Aaron Jones said UWA coordinated a global collaboration of gravitational wave, metasurface and photonics experts to pioneer a new method to measure structures of light called "eigenmodes." ... The proof-of-concept setup the team developed was over one thousand times more sensitive than the original apparatus developed by...

Gravitational waves—ripples in the fabric of Einstein's spacetime—that cross the universe at the speed of light have all sorts of wavelengths, or frequencies. Scientists have not yet managed to detect gravitational waves at extremely low 'nanohertz' frequencies, but new approaches currently being explored are expected to confirm the first low frequency signals quite soon. The main method uses radio telescopes to detect gravitational waves using pulsars—exotic, dead stars, that send out pulses of radio waves with extraordinary regularity. Researchers at the NANOGrav collaboration, for example, use pulsars to time to exquisite precision the rotation periods of a network, or array,...

Gravitational waves are caused by calamitous events in the Universe. Neutron stars that finally merge after circling each other for a long time can create them, and so can two black holes that collide with each other. But sometimes there's a burst of gravitational waves that doesn't have a clear cause. One such burst was detected by LIGO/VIRGO on January 14, and it came from the same region of sky that hosts the star Betelgeuse. Yeah, Betelgeuse, aka Alpha Orionis. The star that has been exhibiting some dimming behaviour recently, and is expected to go supernova at some point in...

Earth's gravitational wave observatories -- which hunt for ripples in the fabric of space-time -- just picked up something weird. The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo detectors recorded an unknown or unanticipated "burst" of gravitational waves on Jan. 14. The gravitational waves we've detected so far usually relate to extreme cosmic events, like two black holes colliding or neutron stars finally merging after being caught in a death spiral. Burst gravitational waves have not been detected before and scientists hypothesize they may be linked to phenomena such as supernova or gamma ray bursts, producing a tiny "pop" when...

Measurements of gravitational waves from approximately 50 binary neutron stars over the next decade will definitively resolve an intense debate about how quickly our universe is expanding, according to findings from an international team that includes University College London (UCL) and Flatiron Institute cosmologists. When neutron stars collide, they emit light and gravitational waves, as seen in this artist's illustration. By comparing the timing of the two emissions from many different neutron star mergers, researchers can measure how fast the universe is expanding. Credit: R. Hurt/Caltech-JPL The cosmos has been expanding for 13.8 billion years. Its present rate of expansion,...

For the first time, two neutron stars in a nearby galaxy have been observed engaging in a spiral death dance around one another until they collided. What resulted from that collision is being called an "unprecedented" discovery that is ushering in a new era of astronomy, scientists announced Monday.

For decades astronomers tried to prove Albert Einstein right by doing what Einstein thought was impossible: detecting the faint ripples in the universe called gravitational waves. They failed repeatedly until two years ago when they finally spotted one. Then another. And another. And another. Three American scientists — including one who initially flunked out of MIT — won the Nobel Prize in physics Tuesday that launched a whole new way to observe the cosmos. Sweden’s Royal Academy of Sciences cited the combination of highly advanced theory and ingenious equipment design in awarding Rainer Weiss of the Massachusetts Institute of Technology...

The Laser Interferometer Gravitational-wave Observatory (LIGO) continues to make waves within the physics community. On June 1, they published their third gravitational wave detection from an observation in early January 2017. This new detection may help vet previously established theories of how these massive mergers behave, and has already provided a new round of observational data to push forward this new kind of astronomy. The confirmed results, published in Physical Review Letters, tell a story of two black holes that coalesced 3 billion light-years from Earth. So far, this is the farthest source from which gravitational waves have been detected...

A momentary chirp rocked the scientific world last week when a team of researchers announced they had detected signals from gravitational waves produced when two black holes, with masses 29 and 36 times the mass of the sun, collided over a billion light years away. Since then, scientists have been giddy over the news. “This detection is the beginning of a new era: The field of gravitational wave astronomy is now a reality,” Gabriela González, a Louisiana State University physics and astronomy professor, said in a statement. But why is this discovery such a big deal?

It took a century, but the theory from Albert Einstein handwritten neatly on paper that is now yellowing has finally been vindicated. Israeli officials on Thursday offered a rare look at the documents where Einstein presented his ideas on gravitational waves, a display that coincided with the historic announcement that scientists had glimpsed the first direct evidence of his theory. [...] In a landmark discovery for physics and astronomy, international scientists announced in Washington on Thursday that they had glimpsed the first direct evidence of gravitational waves, or ripples in space-time. Einstein's theory states that mass warps space and time,...

Scientists are set to make a major announcement Thursday on efforts to pinpoint the existence of gravitational waves, or ripples of space and time that transport energy across the universe. The waves themselves have never before been directly measured, though Albert Einstein said a century ago they were out there, according to his theory of general relativity. They are believed to form around massive objects like black holes and neutron stars, warping space and time. If gravitational waves have been spotted, it would mark one of the biggest scientific discoveries of our time, filling in a major gap in our...

The apocalypse is still on, apparently — at least in a galaxy about 3.5 billion light-years from here. Last winter, a team of Caltech astronomers reported that two supermassive black holes appeared to be spiraling together toward a cataclysmic collision that could bring down the curtains in that galaxy. The evidence was a rhythmic flickering from the galaxy’s nucleus, a quasar known as PG 1302-102, which Matthew Graham and his colleagues interpreted as the fatal mating dance of a pair of black holes with a total mass of more than a billion suns. Their merger, the astronomers calculated, could release...

In the center of most galaxies (ours included) there is a supermassive black hole that holds everything together. However, one galaxy 10.5 billion light years away looks like it might have two black holes, and just like in Highlander, there can be only one. Scientists believe the pair are going to crash into each other in just 21 years. This could provide an unprecedented opportunity to observe the mind-boggling physics of such an event. The galaxy in question doesn’t have a snazzy name — it’s known only as PSO J334.2028+01.4075. It’s what is known as a quasar, or an “active...

Sensitive search fails to find ripples in space, but boosts hopes for future hunts.Supernovas, such as the one which created the Crab Nebula, should send out bursts of gravity waves.NASA The hunt for gravitational waves may not have found the elusive ripples in space-time predicted by Albert Einstein, but the latest results from the most sensitive survey to date are providing clear insight into the origins and fabric of the Universe.General relativity predicts that gravitational waves are generated by accelerating masses. Violent yet rare events, such as a supernova explosion or the collision of two black holes, should make the...