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Most of the times we have looked at Uranus, it has seemed to be a relatively calm place. Well, yes its atmosphere is the coldest place in the solar system. But, when we picture the seventh planet in our solar system invariably the image of a calming blue hazy disc that the spacecraft Voyager 2 took in 1986 comes to mind. Uranus as seen by NASA’s Voyager 2 NASA/JPL-Caltech However, all we have previously known about the atmosphere of Uranus has been ’thrown to the wind’ with observations made last year. In August 2014 a group led by Imke de...

GPS has a new job. It does a great job of telling us our location, but the network of hyper-accurate clocks in space could get a fix on something far more elusive: dark matter. Dark matter makes up 80 per cent of the universe's matter but scarcely interacts with ordinary matter. A novel particle is the most popular candidate, but Andrei Derevianko at the University of Nevada, Reno, and Maxim Pospelov at the Perimeter Institute in Waterloo, Ontario, Canada propose that kinks or cracks in the quantum fields that permeate the universe could be the culprit. If they are right,...

In a startling challenge to the widely-popular Big Bang theory, new evidence, to be published this week in the International Journal of Modern Physics, D, indicates that the universe is not expanding after all. . . .Key contradicted predictions:1)Lithium Prediction: Any superhot explosion throughout the universe, like the Big Bang, would have generated a certain small amount of the light element lithium. Evidence: Yet as astronomers have observed older and older stars, the amount of lithium observed has gotten less and less, and, in the oldest stars is less than one tenth of the predicted level. . . 2) Dark...

Credit: Phys. Rev. Lett. 110, 211302 (2013) (Phys.org) —A team of Harvard University physicists has proposed the possible existence of a type of dark matter not described by current physics models. In their paper published in the journal Physical Review Letters, the team suggests it's possible that not all dark matter is cold and collision-less. In the visible universe, galaxies form into a disk shape—the Milky Way is a good example. All of its members align roughly along a single plane, this due to the forces of gravity and spin. Objects form into masses which, over time, spread out...

Can you give us a sneak preview of your Pittcon plenary lecture ‘Exameter objects to nanometer ones and back again’?What I want to emphasise in this lecture is that the discovery of C60 started off from an interest in massive clouds of gas in interstellar space – some of them are 100 light years across. The chemistry in those clouds is quite fascinating and, in some parts of them, you find carbon is rather abundant. I thought that this carbon was coming out of stars and my interest led to the experiments that uncovered C60. That prompted conjectures about whether...

University of North Dakota scientist Mark Hoffmann's version of Star Search goes a long way -- a very long way -- out into the universe. Hoffmann, a computational chemist, and his colleagues Tryve Helgaker, a well-known Norwegian scientist, and co-authors E.I. Tellgren and K. Lange, also working in Norway, have discovered a molecular-level interaction that science had puzzled over for decades but had never seen. That discovery, it turns out, may redefine how science views chemical compound formation. It also answers questions about what goes on in places like white dwarfs, the super dense cores of stars nearing the end...

Enlarge Image Home sweet home. In the vicinity of the sun, our Milky Way galaxy seems to contain no dark matter, one team of astronomers claims. Credit: Serge Brunier/NASA If a new study is true, then the search for dark matter just got a lot weirder. Our little corner of the Milky Way contains no observable concentration of the mysterious stuff whose gravity binds the galaxy, claims one team of astronomers. That finding would present a major problem for models of how galaxies form and may undermine the whole notion of dark matter, the researchers claim. But some scientists...

A new X-ray study of the remains of an exploded star indicates that the supernova that disrupted the massive star may have turned it inside out in the process. Using long observations of Cassiopeia A (Cas A), a team of scientists has mapped the distribution elements in the supernova remnant in unprecedented detail. This information shows where the different layers of the pre-supernova star are located 300 years after the explosion, and provides insight into the nature of the supernova. The artist’s illustration shows a simplified picture of the inner layers of the star that formed Cas A just before...

A study led by a University of Utah astrophysicist found a new explanation for the growth of supermassive black holes in the center of most galaxies: They repeatedly capture and swallow single stars from pairs of stars that wander too close. Using new calculations and previous observations of our Milky Way and other galaxies, “We found black holes grow enormously as a result of sucking in captured binary star partners,” said Ben Bromley from the University of Utah in Salt Lake City. “I believe this has got to be the dominant method for growing supermassive black holes,” he said. “There...

Einstein is still the boss, say researchers with the BOSS project for measuring key properties of the universe. BOSS, for Baryon Oscillation Spectroscopic Survey, has measured the distance to faraway galaxies more precisely than ever before, mapping the universe as it existed roughly 6 billion years ago, when it was only 63 percent of its current size. The findings suggest that the mysterious “dark energy” causing the universe to expand at an accelerating rate was foreseen by Einstein, the researchers reported April 1 at the American Physical Society meeting. To keep the universe in a static state, Einstein added a...

German astronomers have discovered an ancient planetary system thought to be a survivor of one of the earliest cosmic eras, from 13 billion years ago. The system consists of the star HIP 11952 and two planets. Such an old system will help shed light on planet formation in the early Universe, which occurred under conditions quite different from those of later planetary systems such as our own. Accepted planetary theory states that, generally speaking, a star that contains more 'metals', (i.e. chemical elements other than hydrogen and helium) is more likely to have planets; it is also widely accepted that...

In a paper published in the March 29 issue of the journal Nature, the scientists describe the emergence of “spontaneous coherence,” “spin textures” and “phase singularities” when excitons—the bound pairs of electrons and holes that determine the optical properties of semiconductors and enable them to function as novel optoelectronic devices—are cooled to near absolute zero. This cooling leads to the spontaneous production of a new coherent state of matter which the physicists were finally able to measure in great detail in their basement laboratory at UC San Diego at a temperature of only one-tenth of a degree above absolute zero....

Pulsars, superdense neutron stars, are perhaps the most extraordinary physics laboratories in the universe. Research on these extreme and exotic objects already has produced two Nobel Prizes. Pulsar researchers now are poised to learn otherwise-unavailable details of nuclear physics to test general relativity in conditions of extremely strong gravity, and to directly detect gravitational waves with a “telescope” nearly the size of our galaxy. Neutron stars are the remnants of massive stars that exploded as supernovae. They pack more than the mass of the Sun into a sphere no larger than a medium-sized city, making them the densest objects in...

The moon maybe palely alone in the night sky today but according to scientists it is possible that the there was a second, smaller moon 4.4 billion years ago. A paper published in the journal Nature theorized that there was a smaller moon created in the same impact that created the moon. Astronomers, Martin Jutzi and Erik Asphaug of the University of California at Santa Cruz have long wondered why the moon had two incongruous sides, one smooth with flat plains and another side full of rugged mountains and craters. The astronomers started thinking that the mountainous region had been...

Life as we know it exists on a cozy planet in a stable orbit around a sun shining brightly in its sky. But a new study hints that the most common life in the universe might exist deep inside eternal-night worlds far from any star, adrift in the icy dark of interstellar space. Researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University estimate that "nomad" planets, ejected from their home stellar system and now free-floating through the Milky Way, could outnumber stars by as many as 100,000 to 1. Earlier estimates were more like a...

With all the attention that astronomers have lavished on old Sol over the centuries, you'd think that by now they'd know its diameter to, oh, 10 or 12 significant digits. During the past 40 years, astronomers have attempted to measure the Sun's sizedozens of times using various methods. The dashed line corresponds to a radius of 696,000 km, the value most often used. While the Sun's girth has indeed been measured dozens of times over the past 40 years, the results haven't converged on a single value and scatter by as much as ± 0.1%. One big reason is that,...

U.S. scientists studying "runaway" stars tossed out of our galaxy at great velocities say they've confirmed the same thing can happen to planets. The first runaway star was discovered seven years ago, heading out of the Milky Way at 1.5 million mph, and new research says planets must be doing the same thing -- at speeds up to 30 million mph, the Harvard-Smithsonian Center for Astrophysics reported Thursday. "These warp-speed planets would be some of the fastest objects in our galaxy," astrophysicist Avi Loeb said. "If you lived on one of them, you'd be in for a wild ride from...

Six months after physicists shocked the world by announcing they'd found particles seemingly traveling faster than light, the growing scientific consensus seems to be that the results were flawed. Neutrinos are the vampires of physics. Researchers at the ICARUS project in Italy have recreated an independent version of the original Switzerland-based experiment, called OPERA, and found that their particles traveled at a respectable, sub-light speed. Though the results don't automatically disprove OPERA's findings, they add to most scientists' sense that the shocking finding was an anomaly "The evidence is beginning to point towards the OPERA result being an artifact of...

Lakes on Saturn’s moon Titan don’t do the wave very well. Radar images from NASA’s Cassini spacecraft show glassy smooth surfaces, even on bodies like Ligeia Mare, a large sea roughly 400 kilometers (250 miles) wide. There are patterns on the shoreline of the southern hemisphere's Ontario Lacus that might be from waves, but the features aren’t definitive. Winds haven’t been too high on Titan since Cassini first arrived in Saturn's system in 2004, so the lack of waves is odd but understandable. The ESA’s Huygens probe sent back amazing surface images, including snapshots of delta-looking features, when it made...

When you're building one of the world's most advanced jet fighters, there's no room for error. Engineering technology used by BAE Systems, a partner in the F-35 joint strike fighter program and the manufacturer of Typhoons, even takes the moon's gravitational pull into account. The moon causes the ground to shift by one to two millimeters every time it pulls the oceans' tides in and out. And this tiny movement can throw off the precise alignment of an aircraft's frame as pieces are put together. "That might not sound a lot, but given the tolerances we are working to on...