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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

Exercising In Space

by Faith Brynie and ScienceIQ.com

: Image Courtesy NASA’s Marshall Space Flight Center What did astronaut Shannon Lucid like least about her six months on Space Station Mir? The daily exercise. 'It was just downright hard,' she wrote in Scientific American (May 1998). 'I had to put on a harness and then connect it with bungee cords to a treadmill.' The harness and cords kept her feet on the treadmill. They also provided resistance for her muscles to work against. As Shannon learned, ordinary Earth-style exercises are useless in space. Lifting weights is impossible. A barbell floats like a feather. Crunches are easy but worthless, because the muscles of the abdomen have no upper body weight to lift. Walking and running require little effort, so they can't build muscle strength or maintain the health of heart and blood vessels.

Space travelers experience many other changes in their bodies. One of the first and most noticeable is shrinking of the legs and swelling of the face, as fluids--freed from gravity's pull--redistribute more evenly throughout the body tissues. Each leg loses about a liter of water in the first day, and the legs remain smaller throughout the space flight. The collection of fluid in the head produces a perpetual case of 'space sniffles' that abates only during strenuous exercise. The redistribution of fluid has effects that are more serious, one of which is a form of anemia unique to space travelers. The loss of fluid from the bloodstream to the tissues creates an overabundance of red blood cells. In response, the body produces fewer and destroys more. Astronauts feel the loss when they return to Earth and must work against gravity again.

Exercise is essential to the health and well-being of women and men working in space. Research has shown that astronauts lose bone and muscle mass during their flights. The loss of bone raises calcium levels in the blood, which may lead to kidney stones. NASA planners think resistance exercise using elastic bands should reduce such effects, but whether they can be prevented entirely is unknown. Our experience so far in space shows that all body systems except the skeletal and muscular return to normal after astronauts return to Earth. So far, evidence suggests that human beings can live and work safely in space for long periods, but so far 'long' had meant 'months.' How might humans cope with trips to the other planets that require several years? No one knows.



Kinetic Theory of Gases

Air is a gas, and gases can be studied by considering the small scale action of individual molecules or by considering the large scale action of the gas as a whole. We can directly measure, or sense, ...
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A Chandra X-ray image of The Antennae revealing loops of hot gas spreading out into intergalactic space, huge multimillion degree clouds, and bright emissions from neutron stars and black holes. The image is color coded: low, medium and high energy X-rays are red, green and blue.
The Antennae

NASA's Chandra X-ray Observatory has discovered rich deposits of neon, magnesium, and silicon in a pair of colliding galaxies known as The Antennae. The deposits are located in vast clouds of hot gas. ...
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Planet Jupiter
318 Times as Massive as Earth

What is 318 times more massive than Earth? Jupiter, the fifth planet from the Sun (next in line after Earth and Mars). Jupiter is the largest planet in our Solar System. If you decided to take a Boe ...
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Science Quote

'If I have seen a little further it is by standing on the shoulders of Giants.'

Isaac Newton
(1643-1727)


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