FIRE IN THE SKY: "Never-Before-Seen, Weird And Freakish Object,... We Were Completely Knockout,..." - Hubble Sees Asteroid Spouting Six Comet-like Tails; Astronomers Are Now "Scratching Their Heads" To Find An Adequate Explanation?!

<div style="text-align: justify;"><b><span style="color: yellow;">November 08, 2013 - SPACE </span></b>- Astronomers using NASA's Hubble Space Telescope have identified what they can only describe as a never-before-seen "weird and freakish object" in the asteroid belt that looks like a rotating lawn sprinkler.<br /><br /><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><a href="http://3.bp.blogspot.com/-0ATgk4dM-Pg/UnzyyzEFbTI/AAAAAAABNfo/QAcqNb4mSNk/s1600/freakasteroid.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://3.bp.blogspot.com/-0ATgk4dM-Pg/UnzyyzEFbTI/AAAAAAABNfo/QAcqNb4mSNk/s1600/freakasteroid.jpg" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">This NASA Hubble Space Telescope set of images reveals a never-before-seen set of six comet-like tails <br />radiating from a body in the asteroid belt, designated P/2013 P5. Credit: NASA, ESA, and D. Jewitt (UCLA)</td></tr></tbody></table><br /><br />Normal asteroids should appear simply as tiny points of light. But this asteroid, designated P/2013 P5, has six comet-like tails of dust radiating from it like spokes on a wheel.<br /><br />Because nothing like this has ever been seen before, astronomers are scratching their heads to find an adequate explanation for its out-of-this-world appearance.<br /><br />"We were literally dumbfounded when we saw it," said lead investigator David Jewitt of the University of California at Los Angeles. "Even more amazing, its tail structures change dramatically in just 13 days as it belches out dust. That also caught us by surprise. It's hard to believe we're looking at an asteroid."<br /><br />One interpretation is that the asteroid's rotation rate increased to the point where its surface started flying apart, ejecting dust in episodic eruptions starting last spring. The team rules out a recent asteroid impact scenario because a lot of dust would be blasted into space all at once, whereas P5 has ejected dust for at least five months.<br /><br />The asteroid was discovered as an unusually fuzzy-looking object with the Pan-STARRS survey telescope in Hawaii. The multiple tails were discovered in Hubble images taken on Sept. 10, 2013.<br /><br />When Hubble returned to the asteroid on Sept. 23, its appearance had totally changed. It looked as if the entire structure had swung around. "We were completely knocked out," Jewitt said.<br /><br />Careful modeling by team member Jessica Agarwal of the Max Planck Institute for Solar System Research in Lindau, Germany, showed that the tails could have been formed by a series of impulsive dust-ejection events. She calculated that the first ejection event occurred on April 15 and the last one on Sept. 4. The rest sequentially erupted on July 18, July 24, Aug. 8, and Aug. 26. Radiation pressure from the Sun smears out the dust into streamers.<br /><br />The asteroid could possibly have been spun up if the pressure of sunlight exerted a torque on the body. If the asteroid's spin rate became fast enough, Jewitt said, the asteroid's weak gravity would no longer be able to hold it together. Dust might avalanche downslope towards the equator, and maybe shatter and fall off, eventually drifting into space to make a tail. So far, only a small fraction of the main mass, perhaps 100 to 1,000 tons of dust, has been lost. The 700-foot-radius nucleus is thousands of times more massive.<br /><br />Follow-on observations may show if the dust leaves the asteroid in the equatorial plane, and this would be pretty strong evidence for a rotational breakup. Astronomers will also try to measure the asteroid's true spin rate.<br /><br />Jewitt's interpretation implies that rotational breakup must be a common phenomenon in the asteroid belt; it may even be the main way in which small asteroids die. "In astronomy, where you find one, you eventually find a whole bunch more," Jewitt said. "This is just an amazing object to us, and almost certainly the first of many more to come."<br /><br />The paper from Jewitt's team appears online in the November 7 issue of The Astrophysical Journal Letters. - <a href="http://phys.org/news/2013-11-hubble-asteroid-spouting-comet-like-tails.html#jCp"><span style="color: orange;"><b>PHYSORG</b></span></a>.<br /><br /><br /><br /></div>

Asteroid Comet-like Tails Comets Episodic Eruptions Hubble Space Telescope Multiple Tails NASA P/2013 P5 Pan-STARRS Signs in the Heavens Standard Science Models Tail Structures Unusually Fuzzy FIRE IN THE SKY: "Never-Before-Seen, Weird And Freakish Object,... We Were Completely Knockout,..." - Hubble Sees Asteroid Spouting Six Comet-like Tails; Astronomers Are Now "Scratching Their Heads" To Find An Adequate Explanation?!

November 08, 2013 - SPACE - Astronomers using NASA's Hubble Space Telescope have identified what they can only describe as a never-befor...

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SIGNS IN THE HEAVENS: "Discoveries Are Just Beginning" - Surprising Spiral Structure Found At Galaxy's Supermassive Black Hole?!

<div style="text-align: justify;"><span style="color: yellow;"><b><b><span style="color: yellow;">November 06, 2013 - SPACE </span></b></b></span>- The image above shows the central parts of the nearby active galaxy NGC 1433. The dim blue background image, showing the central dust lanes of this galaxy, comes from the NASA/ESA <a class="zem_slink" href="http://hubble.nasa.gov/" rel="homepage" target="_blank" title="Hubble Space Telescope">Hubble Space Telescope</a>. The colored structures near the center are from recent ALMA observations that have revealed a spiral shape, as well as an unexpected outflow, for the first time.<br /><br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="http://3.bp.blogspot.com/-IOgctlsiRBw/UnpzncmKrQI/AAAAAAABNO4/1XRqkeGsUoE/s1600/galaxyspiral.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://3.bp.blogspot.com/-IOgctlsiRBw/UnpzncmKrQI/AAAAAAABNO4/1XRqkeGsUoE/s1600/galaxyspiral.jpg" /></a></div><br /><br />Two international teams of astronomers have used the power of <a href="http://maps.google.com/maps?ll=-23.0192833333,-67.7531777778&spn=0.01,0.01&q=-23.0192833333,-67.7531777778%20%28Atacama%20Large%20Millimeter%20Array%29&t=h">the Atacama Large Millimeter/submillimeter Array (ALMA)</a> to focus on jets from the huge black holes at the centers of galaxies and observe how they affect their surroundings. They have respectively obtained the best view yet of the molecular gas around a nearby, quiet black hole and caught an unexpected glimpse of the base of a powerful jet close to a distant black hole. <br /><br />There are <a href="http://en.wikipedia.org/wiki/Supermassive_black_hole">supermassive black holes</a> — with masses up to several billion solar masses — at the hearts of almost all galaxies in the Universe, including the Milky Way. In the remote past, these bizarre objects were very active, swallowing enormous quantities of matter from their surroundings, shining with dazzling brilliance, and expelling tiny fractions of this matter through extremely powerful jets. In the current Universe, most supermassive black holes are much less active than they were in their youth, but the interplay between jets and their surroundings is still shaping galaxy evolution. <br /><br />Two new studies, both published today in the journal Astronomy & Astrophysics, used ALMA to probe black hole jets at very different scales: a nearby and relatively quiet black hole in the galaxy NGC 1433 and a very distant and active object called PKS 1830-211. <br /><br />"ALMA has revealed a surprising spiral structure in the molecular gas close to the center of NGC 1433," says Françoise Combes (<a href="http://maps.google.com/maps?ll=48.8364388889,2.33650555556&spn=0.01,0.01&q=48.8364388889,2.33650555556%20%28Paris%20Observatory%29&t=h">Observatoire de Paris</a>, France), who is the lead author of the first paper. "This explains how the material is flowing in to fuel the black hole. With the sharp new observations from ALMA, we have discovered a jet of material flowing away from the black hole, extending for only 150 light-years. This is the smallest such molecular outflow ever observed in an external galaxy." <br /><br />The discovery of this outflow, which is being dragged along by the jet from the central black hole, shows how such jets can stop star formation and regulate the growth of the central bulges of galaxies. This process, called feedback, may explain the mysterious relationship between the mass of a black hole at the centre of a galaxy and the mass of the surrounding bulge. The black hole accretes gas and grows more active, but then produces jets that clear out gas from the surrounding regions and stop star formation. <br /><br />In PKS 1830-211, Ivan Martí-Vidal (<a href="http://maps.google.com/maps?ll=57.6883333333,11.9766666667&spn=0.01,0.01&q=57.6883333333,11.9766666667%20%28Chalmers%20University%20of%20Technology%29&t=h">Chalmers University of Technology</a>, <a href="http://maps.google.com/maps?ll=57.3930555556,11.9177777778&spn=0.01,0.01&q=57.3930555556,11.9177777778%20%28Onsala%20Space%20Observatory%29&t=h">Onsala Space Observatory</a>, Onsala, Sweden) and his team also observed a supermassive black hole with a jet, but a much brighter and more active one in the <a href="http://en.wikipedia.org/wiki/Chronology_of_the_universe">early Universe</a> . It is unusual because its brilliant light passes a massive intervening galaxy on its way to Earth, and is split into two images by gravitational lensing. <br /><br />PKS 1830-211 has a redshift of 2.5, meaning that its light had to travel for about 11 billion years before reaching us. The light we see was emitted when the Universe was just 20% of its current age. By comparison the light from NGC 1433 takes only about 30 million years to reach the Earth, a very short time in galactic terms. <br /><br />Einstein’s theory of general relativity predicts that light rays will be deflected as they pass a massive object such as a galaxy. This effect is called gravitational lensing and, since the first find in 1979, numerous such <a href="http://en.wikipedia.org/wiki/Gravitational_lens">gravitational lenses</a> have been discovered. The lensing can create multiple images as well as distort and magnify the background light sources. <br /><br />From time to time, supermassive black holes suddenly swallow a huge amount of mass, which increases the power of the jet and boosts the radiation up to the very highest energies. And now ALMA has, by chance, caught one of these events as it happens in PKS 1830-211. The infalling material could be a star or a molecular cloud. Such an infalling cloud has been observed at the center of the Milky Way. <br /><br />"The ALMA observation of this case of black hole indigestion has been completely serendipitous. We were observing PKS 1830-211 for another purpose, and then we spotted subtle changes of colour and intensity among the images of the gravitational lens. A very careful look at this unexpected behaviour led us to the conclusion that we were observing, just by a very lucky chance, right at the time when fresh new matter entered into the jet base of the black hole," says Sebastien Muller, a co-author of the second paper. <br /><br />The team also looked to see whether this violent event had been picked up with other telescopes and were surprised to find a very clear signal in gamma rays, thanks to monitoring observations with NASA's <a href="http://fermi.gsfc.nasa.gov/">Fermi Gamma-ray Space Telescope</a>. The process that caused the increase of radiation at ALMA’s long wavelengths was also responsible of boosting the light in the jet dramatically, up to the highest energies in the Universe. This energy is emitted as gamma rays, the shortest wavelength and highest energy form of electromagnetic radiation. <br /><br />"This is the first time that such a clear connection between gamma rays and submillimetre radio waves has been established as coming from the real base of a black hole's jet," adds Sebastien Muller. <br /><br />The two new observations are just the start of ALMA's investigations into the workings of jets from supermassive black holes, near and far. Combes’s team is already studying other nearby active galaxies with ALMA and the unique object PKS 1830-211 is expected to be the focus of much future research with ALMA and other telescopes. <br /><br />"There is still a lot to be learned about how black holes can create these huge energetic jets of matter and radiation," concludes Ivan Martí-Vidal. “But the new results, obtained even before ALMA was completed, show that it is a uniquely powerful tool for probing these jets — and the discoveries are just beginning!" - <a href="http://www.dailygalaxy.com/my_weblog/2013/11/surprising-spiral-structure-found-at-galaxy-centers-supermassive-black-hole.html"><span style="color: orange;"><b>Daily Galaxy</b></span></a>.<br /><br /><br /><br /></div>

ALMA Black Hole Jets Cosmic Energies ESA Galaxy NGC 1433 Gravitational Lenses Hubble Space Telescope Milky Way NASA Signs in the Heavens Spiral Structure Supermassive Black Hole Unexpected Outflow SIGNS IN THE HEAVENS: "Discoveries Are Just Beginning" - Surprising Spiral Structure Found At Galaxy's Supermassive Black Hole?!

November 06, 2013 - SPACE - The image above shows the central parts of the nearby active galaxy NGC 1433. The dim blue background image, s...

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