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<p>How Gravity Can Bend Starlight</p>

<p>This illustration reveals how the gravity of a white dwarf star warps space and bends the light of a distant star behind it.</p>

<p>White dwarfs are the burned-out remnants of normal stars. The Hubble Space Telescope captured images of the dead star, called Stein 2051 B, as it passed in front of a background star. During the close alignment, Stein 2051 B deflected the starlight, which appeared offset by about 2 milliarcseconds from its actual position. This deviation is so small that it is equivalent to observing an ant crawl across the surface of a quarter from 1,500 miles away. From this measurement, astronomers calculated that the white dwarf's mass is roughly 68 percent of the sun's mass.</p>

<p>Stein 2051 B resides 17 light-years from Earth. The background star is about 5,000 light-years away. The white dwarf is named for its discoverer, Dutch Roman Catholic priest and astronomer Johan Stein.</p>
Observation confirms Einsteins general theory of relativity.
Astronomers have used NASA Hubble Space Telescope to repeat a century-old test of Einsteins general theory of relativity
<p>This image, taken by NASA's Hubble Space Telescope, reveals an unusual sight: a runaway quasar fleeing from its galaxy's central hub. A quasar is the visible, energetic signature of a black hole. Black holes cannot be observed directly, but they are the energy source at the heart of quasars — intense, compact gushers of radiation that can outshine an entire galaxy.</p>

<p>The green dotted line marks the visible periphery of the galaxy. The quasar, named 3C 186, appears as a bright star just off-center. The quasar and its host galaxy reside 8 billion light-years from Earth. Researchers estimate that it took the equivalent energy of 100 million supernovas exploding simultaneously to jettison the black hole. The most plausible explanation for this propulsive energy is that the monster object was given a kick by gravitational waves unleashed by the merger of two hefty black holes at the center of the host galaxy.</p>

<p>The Hubble image combines visible and near-infrared light taken by the Wide Field Camera 3.</p>

<p>Courtesy: NASA</p>
Gravitational Wave Kicks Monster Black Hole Out of Galactic Core
Astronomers have uncovered a supermassive black hole that has been propelled out of the center of a distant galaxy by what could be the awesome power of gravitational waves.

<p>Composite ALMA and optical image of a young Milky Way-like galaxy 12 billion light-years away and a background quasar 12.5 billion light-years away. Light from the quasar passed through the galaxy's gas on its way to Earth, revealing the presence of the galaxy to astronomers. New ALMA observations of the galaxy's ionized carbon (green) and dust continuum (blue) emission show that the dusty, star-forming disk of the galaxy is vastly offset from the gas detected by quasar absorption at optical wavelengths (red). This indicates that a massive halo of gas surrounds the galaxy. The optical data are from the Keck I Telescope at the W.M. Keck Observatory. Credit: ALMA (ESO/NAOJ/NRAO), M. Neeleman & J. Xavier Prochaska; Keck Observatory</p>
Milky Way-like Galaxies in Early Universe Embedded in 'Super Halos'
By harnessing the extreme sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers have directly observed a pair of Milky Way-like galaxies seen when the universe was only eight percent of its current age.
<p>NEOS Detector</p>

<p>Courtesy: ibs</p>
Finding the 'Ghost Particles' Might be More Challenging
Results from the NEOS experiment on sterile neutrinos differ partly from the theoretical expectations.


Earth’s Magnetic Field Reveals Details Of A Dramatic Past
ESA’s Swarm satellites are seeing fine details in one of the most difficult layers of Earth’s magnetic field to unpick – as well as our planet’s magnetic history imprinted on Earth’s crust.
Scientists Evade The Heisenberg Uncertainty Principle
The study, published in Nature, reports a technique to bypass the Heisenberg uncertainty principle.
Using Light to Control Curvature of Plastics
Researchers have developed a technique that uses light to get two-dimensional (2-D) plastic sheets to curve into three-dimensional (3-D) structures, such as spheres, tubes or bowls.

Science Facts

New Evidence Points to a Gamma-Ray Burst... In Our Own Backyard

by NASA Headquarters and ScienceIQ.com

A composite Chandra X-ray (blue) and Palomar infrared (red and green) image of the supernova remnant W49B.: Image Courtesy X-ray: NASA/Chandra X-ray Center/Spitzer Science Center; Infrared: Caltech/Palomar Only 35,000 light years away lies W49B, the supernova remnant left over from the cataclysmic burst. New evidence pointing to a gamma ray burst origin for this remnant was discovered by X-ray data from the Chandra X-ray Observatory, combined with infrared observations from the Palomar 200-inch telescope in southern California. The discovery is exciting for two reasons. It may be the first time a supernova remnant from a gamma-ray burst has been found so close to Earth. It also appears to be tied to a special type of black hole called a 'collapsar,' which was first theorized by scientists more than a decade ago. 'The nearest known gamma-ray burst to Earth is several million light years away -- most are billions of light years distant -- so the detection of the remnant of one in our own galaxy would be a major breakthrough,' said William Reach of the California Institute of Technology. W49B is barrel-shaped and ringed by bright, infrared 'hoops.'

But one of its most intriguing features is the intense X-radiation produced by concentrations of iron and nickel ions along the axis of the barrel. This makes it 'a prime candidate for being the remnant of a gamma-ray burst involving a black hole collapsar,' according to Jonathan Keohane of NASA's Jet Propulsion Laboratory in Pasadena, Calif. In a traditional supernova, only the outer parts of the star are flung outward during the explosion. But in the collapsar model, iron and nickel from the center of the exploding star is ejected outward along the jets of hot gas. W49B appears to fit the collapsar pattern. For more than a decade, astronomers have suspected that gamma-ray bursts are produced when the core of a massive star collapses, forming a black hole collapsar. A disk of superhot, magnetized gas spins rapidly around the black hole, which pulls in most of the gas. But some is hurled outward in opposite directions at nearly the speed of light.

An observer in the path of one of these jets would be blinded by a gamma-ray burst packing as much power as ten quadrillion suns. Until the discovery of W49B, there was a problem with the collapsar theory. Massive stars -- stars large enough to form collapsars -- are usually formed in a dense cloud of dust. But the afterglow of gamma-ray bursts seem to point to the explosion taking place in a low-density gas. Keohane and his colleagues believe barrel-shaped W49B nebula may help solve that problem. The infrared image reveals four rings of warm gas that were most likely flung away from the star a few hundred thousand years before the explosion. A hot wind blowing from the star pushed these rings even further outward. By the time of its collapse, the star had carved out a low-density cavity immediately around itself. 'This star appears to have exploded inside a bubble it had created,' Keohane of said. 'In a sense, it dug its own grave.'


Hydra A is a galaxy cluster that is 840 million light years from Earth (redshift = .054). The cluster gets its name from the strong radio source, Hydra A, that originates in a galaxy near the center of the cluster.
Groups & Clusters of Galaxies

Galaxy clusters are the largest gravitationally bound objects in the universe. They have three major components: (i) hundreds of galaxies containing stars, gas and dust; (ii) vast clouds of hot (30 - ...
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Aerosol Sprays

Liquid forced through a small orifice under pressure will come out Is a spray of fine droplets, or mist, rather than as a stream, or jet. A 'squirt gun' works the same way, as does the kitchen faucet ...
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What Powered the Big Bang?

During the last decade, sky maps of the radiation relic of the Big Bang---first by NASA's Cosmic Background Explorer (COBE) satellite and more recently by other experiments, including Antarctic balloo ...
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Science Quote

'To myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.'

Isaac Newton
(1643-1727)


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