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In the far future, we could reveal detailed views of distant worlds by turning our home star into a gravitational lens Diagram showing a conceptual imaging technique that uses the sun’s gravitational field to magnify light from exoplanets. This would allow for highly advanced reconstructions of what exoplanets look like. We now know of more than 5,000 exoplanets beyond the solar system. What we really understand about each of these worlds, though, is barely anything at all. Most of them have been seen only indirectly from their shadows as they cross in front of the stars they orbit. The...

Thanks to a new analysis technique, precision measurements of the Earth-Moon distance should improve estimates of the size of the gravitational-wave background. NASA Precise measurements of the Earth-Moon distance can allow researchers to estimate the maximum possible amplitude of the steady background “hum” of gravitational waves. (This time-lapse series of photos was taken by a satellite a million miles from Ea... Show more The barrage of all gravitational waves that continuously hit Earth in the microhertz frequency range—roughly one oscillation every few weeks—might be detected by measuring their subtle effects on the Earth-Moon system. By exploiting this decades-old idea, researchers...

What a Perfect Gravitational LensA stunning new photograph from the Hubble Space Telescope shows a nearly perfect Einstein Ring, an effect caused by gravitational lensing. This is one of the most complete Einstein Rings ever seen. Gravitational lenses occur when a massive object, such as a galaxy, is aligned directly between Earth and another massive object even farther away. Einstein predicted that gravity could bend light, and this image is a wonderful example of how gravity from foreground objects causes a deflection of light from background objects, forming a ring of light.In this case, it’s not just one foreground...

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...

A Neutrino Beam Beaconby Paul Gilsteron May 17, 2019 If you want to look for possible artifacts of advanced civilizations, as do those practicing what is now being called Dysonian SETI, then it pays to listen to the father of the field. My friend Al Jackson has done so and offers a Dyson quote to lead off his new paper: “So the first rule of my game is: think of the biggest possible artificial activities with limits set only by the laws of physics and look for those.” Dyson wrote that in a 1966 paper that repays study today (citation...

In new study, UChicago astronomers find no evidence for extra spatial dimensions to the universe based on gravitational wave data. Credit: Courtesy of NASA’s Goddard Space Flight Center CI Lab While last year's discovery of gravitational waves from colliding neutron stars was earth-shaking, it won't add extra dimensions to our understanding of the universe—not literal ones, at least. University of Chicago astronomers found no evidence for extra spatial dimensions to the universe based on the gravitational wave data. Their research, published in the Journal of Cosmology and Astroparticle Physics, is one of many papers in the wake of the extraordinary...

How to Listen to the Background Hum of Gravitational Waves From all the Black Holes Colliding into Each Other Article written: 18 Apr , 2018 by Matt Williams The first-ever detection of gravitational waves (which took place in September of 2015) triggered a revolution in astronomy. Not only did this event confirm a theory predicted by Einstein’s Theory of General Relativity a century before, it also ushered in a new era where the mergers of distant black holes, supernovae, and neutron stars could be studied by examining their resulting waves.In addition, scientists have theorized that black hole mergers could actually...

Gravitational Lensing Provides Rare Glimpse Into Interiors of Black Holes Article written: 17 Aug , 2017 by Matt Williams The observable Universe is an extremely big place, measuring an estimated 91 billion light-years in diameter. As a result, astronomers are forced to rely on powerful instruments to see faraway objects. But even these are sometimes limited, and must be paired with a technique known as gravitational lensing. This involves relying on a large distribution of matter (a galaxy or star) to magnify the light coming from a distant object.Using this technique, an international team led by researchers from the California...

Astronomers want to harness [the Sun's] spacetime-warping gravity as a lens to image the surface of exoplanets in astonishing detail The bluish ring is a distant galaxy whose image has been magnified and warped by the gravity of a reddish galaxy in the foreground Credit: ESA/Hubble & NASA Wikimedia Within just a few years, astronomers may at last find a planet that shows signs of life as we know it, in the form of atmospheric gases that betray signs of biological activity. This would be a transformational event for our civilization. But, what would we do next? How could we...

Explanation: A new sky is becoming visible. When you look up, you see the sky as it appears in light -- electromagnetic radiation. But just over the past year, humanity has begun to see our once-familiar sky as it appears in a different type of radiation -- gravitational radiation. Today, the LIGO collaboration is reporting the detection of GW151226, the second confirmed flash of gravitational radiation after GW150914, the historic first detection registered three months earlier. As its name implies, GW151226 was recorded in late December of 2015. It was detected simultaneously by both LIGO facilities in Washington and Louisiana,...

On 26 December 2015, LIGO detected gravitational waves from two black holes spiraling together.LIGO/T. Pyle LIGO detects another black hole crash By Adrian ChoJun. 15, 2016 , 1:15 PM The biggest discovery in science this year--the observation of ripples in space-time called gravitational waves--was no fluke. For a second time, physicists working with the two massive detectors in the Laser Interferometer Gravitational-Wave Observatory (LIGO) have detected a pulse of such waves, the LIGO team reported on 15 June at a meeting of the American Astronomical Society in San Diego, California. Once again the waves emanated from the merger of...

The Future of Gravitational Wave Astronomy Fully opening this new window on the universe will take decades--even centuries By Lee Billings on February 12, 2016 Share on Facebook Share on Twitter Share on Reddit Email Print Share via Google+Stumble Upon A simulated view of gravitational waves rippling out from merging black holes. The reddish waves correspond to those recently detected from a real black-hole merger by the Laser Interferometer Gravitational-wave Observatory (LIGO).Credit: NASA/C. Henze Advertisement A century ago, when Albert Einstein first predicted the existence of gravitational waves--subtle ripples in spacetime produced by massive objects hurtling through the cosmos--he also...

Pondering Gravitational Wavesby Paul Gilster on February 11, 2016 "Einstein would be beaming," said National Science Foundation director France Córdova as she began this morning's news conference announcing the discovery of gravitational waves. I can hardly disagree, because we have in this discovery yet another confirmation of the reality of General Relativity. Caltech's Kip Thorne, who discussed black hole mergers way back in 1994 in his book Black Holes and Time Warps, said at the same news conference that Einstein must have been frustrated by the lack of available technologies to detect the gravitational waves his theory predicted, a lack...

More Gravitational Wave Rumors: Colliding Black Holes? By Ian O'Neill, Discovery News February 9, 2016 08:15am ET MORE This computer simulation shows the production of gravitational waves during a black hole collision.Credit: MPI for Gravitational Physics/W.Benger-Zib More gravitational wave discovery rumors are flying, but this time they've taken a specific -- and, possibly, really exciting -- new twist. And what's more, we should find out whether the astrophysical rumor mill is correct or not by the end of this week; a National Science Foundation press announcement is planned for 10:30 a.m. ET on Thursday (Feb. 11), billed as an opportunity...

Sometimes you have to think outside the box. Faced with some of the universe’s most stubborn mysteries, such as the identity of dark matter, physicists are turning to a technique that employs the weird laws of quantum mechanics: atom interferometry. Atom interferometers allow the study of various physical phenomena by splitting atom waves using a nanograting, such as this one. Composed of silicon nitride, this grating, imaged with a scanning electron microscope, has a period of 100 nm. Image courtesy of Alex Cronin (University of Arizona, Tucson, AZ). This method, which takes advantage of the fact that quantum particles behave...

New insights found in black hole collisions Mar 27, 2015 Enlarge Black Holes Go 'Mano a Mano.' Credit: NASA, Chandra, 10/06/09 New research provides revelations about the most energetic event in the universe—the merging of two spinning, orbiting black holes into a much larger black hole. An international team of astronomers, including from the University of Cambridge, have found solutions to decades-old equations describing what happens as two spinning black holes in a binary system orbit each other and spiral in toward a collision.The results, published in the journal Physical Review Letters, should significantly impact not only the study of...

Gravitational Lensing in Proxima Planet Hunt by Paul Gilster on June 4, 2013 I normally think about gravitational lensing as a way of finding planets that are a long way from home. That’s just the nature of the beast: Lensing as an exoplanet detection tool depends upon a star with planets moving in front of a background object, its mass ‘bending’ space enough to cause slight changes to the image of the farther star. Monitor those changes closely enough and you may see the signature of a second disruption, flagging the presence of a planet around the closer star. Occultations...

A Deep-Sky Look at Lensing by Paul Gilster on January 13, 2011 As we continue to investigate the parameters of the proposed FOCAL mission to the SunÂ’s gravitational lens, itÂ’s worth recalling how the idea of lensing has taken hold in recent decades. Einstein noted the possibilities of such lensing as far back as 1936, but it wasnÂ’t until 1964 that Sydney Liebes (Stanford University) worked out the mathematical theory, explaining how a galaxy between the Earth and an extremely distant object like a quasar could focus the latterÂ’s light in ways that should be detectable by astronomers. And...

A FOCAL Mission into the Oort Cloud by Paul Gilster on November 15, 2010 After all this time, IÂ’m still trying to wrap my head around the idea of massive objects in space as lenses, their distortion of spacetime offering the ability to see distant objects at huge magnification. On Friday we saw how the lensing effect caused by galactic clusters can be used to study dark energy. And consider the early results from the Herschel-ATLAS project, conducted by ESAÂ’s Herschel Space Observatory. Herschel is scanning large areas of the sky in far-infrared and sub-millimeter light. Many of its...