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Thorfinn Hrolfsson
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For the first time, scientists have observed ripples in the fabric of space-time called gravitational waves, arriving at the earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein’s 1915 general theory of relativity and opens an unprecedented new window onto the cosmos.

Gravitational waves carry information about their dramatic origins and about the nature of gravity that cannot otherwise be obtained. Physicists have concluded that the detected gravitational waves were produced during the final fraction of a second of the merger of two black holes to produce a single, more massive spinning black hole. This collision of two black holes had been predicted but never observed.

The gravitational waves were detected on September 14, 2015 at 5:51 a.m. Eastern Daylight Time (09:51 UTC) by both of the twin Laser Interferometer Gravitational-wave Observatory (LIGO) detectors, located in Livingston, Louisiana, and Hanford, Washington, USA. The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. The discovery, accepted for publication in the journal Physical Review Letters, was made by the LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the Virgo Collaboration using data from the two LIGO detectors.
For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at the earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein's 1915 general theory of relativity and opens an unprecedented new window onto the cosmos.
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One of the UK's foremost experts on black holes, Prof Stephen Hawking, told the BBC's Pallab Ghosh that the discovery was ground breaking.
Acclaimed physicist Professor Stephen Hawking says the first observation of gravitational waves is "groundbreaking".
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Will they be able to verify inflation with LIGO?
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Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor.

Despite being just 250 million light years from Earth--very close in astronomical terms--the new galaxies had been hidden from view until now by our own galaxy, the Milky Way.

Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space.

more at:
1> 'The Parkes HI Zone of Avoidance Survey', published in the Astronomical Journal February 9th, 2016. Available from http://bit.ly/1nHeAwR 2> High resolution images and animations are available from http://www.icrar.org/hidden-galaxies
Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth, the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the Milky W...
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Brilliant 
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Every school kid learns the basic structure of the Earth: a thin outer crust, a thick mantle, and a Mars-sized core. But is this structure universal? Will rocky exo-planets orbiting other stars have the same three layers? New research suggests that the answer is yes - they will have interiors very similar to Earth.

"We wanted to see how Earth-like these rocky planets are. It turns out they are very Earth-like," says lead author Li Zeng of the Harvard-Smithsonian Center for Astrophysics (CfA).

To reach this conclusion Zeng and his co-authors applied a computer model known as the Preliminary Reference Earth Model (PREM), which is the standard model for Earth's interior. They adjusted it to accommodate different masses and compositions, and applied it to six known rocky exo-planets with well-measured masses and physical sizes.

They found that the other planets, despite their differences from Earth, all should have a nickel/iron core containing about 30 percent of the planet's mass. In comparison, about a third of the Earth's mass is in its core. The remainder of each planet would be mantle and crust, just as with Earth.

"We've only understood the Earth's structure for the past hundred years. Now we can calculate the structures of planets orbiting other stars, even though we can't visit them," adds Zeng.
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Don't get me wrong, I appreciate the study/measure of standard model, but I believe the only true measure is to desen within.
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Thorfinn Hrolfsson

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Oh Earth, your curves are wayyyy sexy! Via Unofficial: Dr. Jack Wolfson
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Located about 300 million light-years away in the Coma Cluster, the giant elliptical galaxy NGC 4889, the brightest and largest galaxy in this image, is home to a record-breaking super massive black hole. Twenty-one billion times the mass of the Sun, this black hole has an event horizon — the surface at which even light cannot escape its gravitational grasp — with a diameter of approximately 130 billion kilometres. This is about 15 times the diameter of Neptune’s orbit from the Sun. By comparison, the super massive black hole at the centre of our galaxy, the Milky Way, is believed to have a mass about four million times that of the Sun and an event horizon just one fifth the orbit of Mercury.

But the time when NGC 4889’s black hole was swallowing stars and devouring dust is past. Astronomers believe that the gigantic black hole has stopped feeding, and is currently resting after feasting on NGC 4889’s cosmic cuisine. The environment within the galaxy is now so peaceful that stars are forming from its remaining gas and orbiting undisturbed around the black hole.
The placid appearance of NGC 4889 can fool the unsuspecting observer. But the elliptical galaxy, pictured in this new image from the NASA/ESA Hubble Space Telescope, harbours a dark secret. At its heart lurks one of the most massive black holes ever discovered.
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A newly formed star lights up the surrounding cosmic clouds in this new image from ESO’s La Silla Observatory in Chile. Dust particles in the vast clouds that surround the star HD 97300 diffuse its light, like a car headlight in enveloping fog, and create the reflection nebula IC 2631. Although HD 97300 is in the spotlight for now, the very dust that makes it so hard to miss heralds the birth of additional, potentially scene-stealing, future stars.

The glowing region in this new image from the MPG/ESO 2.2-metre telescope is a reflection nebula known as IC 2631. These objects are clouds of cosmic dust that reflect light from a nearby star into space, creating a stunning light show like the one captured here. IC 2631 is the brightest nebula in the Chamaeleon Complex, a large region of gas and dust clouds that harbours numerous newborn and still-forming stars. The complex lies about 500 light-years away in the southern constellation of Chamaeleon.
ESO, European Organisation for Astronomical Research in the Southern Hemisphere
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Does anyone know why the bright stars in this pic are not concentric with the "halos" surrounding the stars?

[ Seen better here, in this link --  http://www.eso.org/public/images/eso1605a/ ]

Must be something to do with the optics of the telescope? Herschelian off-axis focus?
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Science said it had seen an email saying Krauss was right. Quoting from the email, the mag wrote "spies who have seen the paper say they have seen gravitational waves from a binary black hole merger ... Apparently the signal is spectacular."

The two black holes are claimed to be equivalent to 29 and 36 solar masses, and the signal is described as being of 5.1 sigma (which is a high enough confidence that it would be classed as a "discovery," if it's confirmed).
The press conference is timed to coincide with the release of the LIGO collaboration's paper in Nature.
LIGO Scientific Collaboration (LSC) seeks to detect gravitational waves and use them for exploration of fundamentals of science.
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Spies? Why are these people sabotaging each other? Seems counter productive. 
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The Reith Lectures is a series of annual radio lectures given by leading figures of the day, commissioned by the BBC and broadcast on BBC Radio 4 and the BBC World Service. The lectures were inaugurated in 1948 by the BBC to mark the historic contribution made to public service broadcasting by Sir John Reith, the corporation's first director-general.
https://en.wikipedia.org/wiki/Reith_Lectures
Professor Stephen Hawking delivers the first of his two BBC Reith Lectures on black holes. These collapsed stars challenge the very nature of space and time, as they contain a singularity - a phenomenon where the normal rules of the universe break down. They have held an enduring fascination for Professor Hawking throughout his life. Rather than see them as a scary, destructive and dark he says if properly understood, they could unlock the deepes...
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another Pic of the week and some great shots in the set
Here are a selection of photos sent in by ABC Open audience members from around Australia. If you have any photos you'd like to share with ABC Open, send them via their . You can also Instagram your photo by using #abcmyphoto
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An international team led by a researcher from Hiroshima University has succeeded in revealing the detailed structure of a massive ionized gas outflow streaming from the star burst galaxy NGC 6240 (Figure 1). The team used the Suprime-Cam mounted on the 8.2-meter Subaru Telescope on Maunakea in Hawaii.

The ionized gas the astronomers observed extends across 300,000 light-years and is carried out of the galaxy by a powerful super wind. That wind is driven by intense star-forming activity at the galactic centre. The light-collecting power and high spatial resolution of Subaru Telescope made it possible to study, for the first time, the complex structure of one of the largest known super winds being driven by star birth – and star death.
Press Release. A Violent Wind Blown from the Heart of a Galaxy Tells the Tale of a Merger. February 3, 2016. An international team led by a researcher from Hiroshima University has succeeded in revealing the detailed structure of a massive ionized gas outflow streaming from the starburst galaxy ...
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Astronomers have used the ALMA and IRAM telescopes to make the first direct measurement of the temperature of the large dust grains in the outer parts of a planet-forming disc around a young star. By applying a novel technique to observations of an object nicknamed the Flying Saucer they find that the grains are much colder than expected: −266 degrees Celsius. This surprising result suggests that models of these discs may need to be revised.
The international team, led by Stephane Guilloteau at the Laboratoire d'Astrophysique de Bordeaux, France, measured the temperature of large dust grains around the young star 2MASS J16281370-2431391 in the spectacular Rho Ophiuchi star formation region, about 400 light-years from Earth.

This star is surrounded by a disc of gas and dust — such discs are called proto planetary discs as they are the early stages in the creation of planetary systems. This particular disc is seen nearly edge-on, and its appearance in visible light pictures has led to its being nicknamed the Flying Saucer.

The astronomers used the Atacama Large Millimetre/submillimetre Array (ALMA) to observe the glow coming from carbon monoxide molecules in the 2MASS J16281370-2431391 disc. They were able to create very sharp images and found something strange — in some cases they saw a negative signal! Normally a negative signal is physically impossible, but in this case there is an explanation, which leads to a surprising conclusion.
ESO, European Organisation for Astronomical Research in the Southern Hemisphere
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