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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

Amazing GRACE

by NASA Headquarters and ScienceIQ.com

An uneven distribution of mass inside the Earth. The Earth Gravity has an effect on everyone and everything on Earth. Although we can't see it, smell it, taste it or touch it, we know it's there. Although scientists already know quite a bit about this invisible force, many aspects of this fundamental force of nature remain mysterious. In 2002 NASA teamed-up with the German Space Agency to launch the dual satellites that make up GRACE, short for the Gravity Recovery And Climate Experiment. These uniquely-designed twin satellites were developed to provide detailed measurements of Earth's gravity field that help scientists better understand the effects gravity has on Earth's global climate change.

Scientists have studied Earth's gravity for more than 30 years, using both satellite and ground measurements that were of uneven quality,' said Dr. Michael Watkins, GRACE project scientist at NASA's Jet Propulsion Laboratory in California. Errors in some locations were off by as much as 3 feet. Now, these measurements can be taken to within about 1 centimeter (0.4 inches) of accuracy. 'That's progress,' Watkins said. Why do the sensors need to be that sensitive? Because the variations in gravity across Earth's surface are very small and the weight of an object is not the same at every point on Earth. We live on a lumpy, bumpy planet scattered with mountains, valleys and caverns. These features have slightly different masses so as a result, the gravitational force changes ever so slightly across the surface of the Earth.

GRACE maps out these sensitive gravitational changes. GRACE can detect changes as small as one-tenth of the width of a human hair in the separation of the two spacecraft. This distance measurement is combined with Global Positioning data that gives the precise location of the measurement over Earth's surface. Every 30 days, scientists produce gravity maps that are 1,000 times more accurate then maps previously produced that had errors too large to be useful. GRACE monitors the mass and location of water as it moves around on the surface of the Earth, cycling between the land, oceans, and polar ice caps. Scientists also know that gravity is responsible for keeping the air and clouds from drifting away into space, creating the ups and downs of the ocean tides and a force that pulls two objects together. Gravity may be known as the weakest force in all of nature, but it still keeps our feet on the ground and manages to hold our galaxies and solar system together.


Pluto and Charon are tough to see even with the best telescopes.
Pluto Is Way Out There

Long considered to be the smallest, coldest, and most distant planet from the Sun, Pluto may also be the largest of a group of objects that orbit in a disk-like zone of beyond the orbit of Neptune cal ...
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Artist Rendition of Pluto, its moon Charon and spacecraft.
Pluto: Beyond Neptune Or Not?

Did I catch you? Pluto (newly classified as a dwarf-planet) comes after planet Neptune. Right? Depends. Pluto takes 248 years to orbit the Sun. Most of that time Pluto's orbit puts it outside the orbi ...
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Right Ascension & Declination

Right Ascension (abbreviated R.A.) and Declination (abbreviated Dec) are a system of coordinates used by astronomers to keep track of where stars and galaxies are in the sky. They are similar to the s ...
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Science Quote

'My scientific work is motivated by an irresistible longing to understand the secrets of nature and by no other feelings.'

Albert Einstein
(1879-1955)


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