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Solar Eclipse 2017
On August 21, 2017, all of North America was treated to an eclipse of the sun. Viewers around the world can now see a wealth of images captured before, during, and after the eclipse by 11 spacecraft, at least three NASA aircraft, more than 50 high-altitude balloons, and the astronauts aboard the International Space Station – each offering a unique vantage point for the celestial event.

Click here to view the 2017 solar eclipse photos

<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

Backyard Telescopes for New Planets. Is it Possible?

by NASA Headquarters and ScienceIQ.com

Artist Fifteen years ago, the largest telescopes in the world had yet to locate a planet orbiting another star. Today telescopes no larger than those available in department stores are proving capable of spotting previously unknown worlds. A newfound planet detected by a small, 4-inch-diameter telescope demonstrates that we are at the cusp of a new age of planet discovery. Soon, new worlds may be located at an accelerating pace, bringing the detection of the first Earth-sized world one step closer. This is the first extrasolar planet discovery made by a dedicated survey of many thousands of relatively bright stars in large regions of the sky. It was made using the Trans-Atlantic Exoplanet Survey (TrES), a network of small, relatively inexpensive telescopes designed to look specifically for planets orbiting bright stars. A team of scientists co-led by Edward Dunham of Lowell Observatory, Timothy Brown of NCAR, and David Charbonneau (CfA), developed the TrES network.

The network's telescopes are located in Palomar Observatory (California, USA), Lowell Observatory (Arizona, USA), and the Canary Islands (Spain). Although the small telescopes of the TrES network made the initial discovery, follow-up observations at other facilities were required. Observations at the W. M. Keck Observatory which operates the world's two largest telescopes in Hawaii for the University of California, Caltech, and NASA, were particularly crucial in confirming the planet's existence. The newfound planet is a Jupiter-sized gas giant orbiting a star located about 500 light years from the Earth in the constellation Lyra. This world circles its star every 3.03 days at a distance of only 4 million miles (6 million kilometers), much closer and faster than the planet Mercury in our solar system.

Although such planets are relatively common, astronomers used an uncommon technique to discover it. This world was found by the 'transit method,' which looks for a dip in a star's brightness when a planet crosses directly in front of the star and casts a shadow. A Jupiter-sized planet blocks only about 1/100th of the light from a Sun-like star, but that is enough to make it detectable. To be successful, transit searches must examine many stars because we only see a transit if a planetary system is located nearly edge-on to our line of sight. A number of different transit searches currently are underway. Most examine limited areas of the sky and focus on fainter stars because they are more common, thereby increasing the chances of finding a transiting system. However the TrES network concentrates on searching brighter stars in larger swaths of the sky because planets orbiting bright stars are easier to study directly.


Among the biggest challenges for GP-B is keeping its Science Instrument Assembly constantly cooled to a temperature of 1.8 Kelvin, or minus 271.4 degrees Celsius (slightly above absolute zero), which will last 18 to 24 months.
GP-B: More Than Just a Pretty Face

Questions about the ways space, time, light and gravity relate to each other have been asked for eons. Theories have been offered, yet many puzzles remain to be solved. No spacecraft ever built has re ...
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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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The Equivalence Principle

Four hundred years ago--or so the story goes--Galileo Galilei started dropping things off the Leaning Tower of Pisa: Cannon balls, musket balls, gold, silver and wood. He might have expected the heavi ...
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Science Quote

'A theory with mathematical beauty is more likely to be correct than an ugly one that fits some experimental data. God is a mathematician of a very high order, and He used very advanced mathematics in constructing the universe.'

Paul Dirac
(1902-1984)


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