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Explanation: What's happened to the center of this galaxy? Unusual and dramatic dust lanes run across the center of elliptical galaxy Centaurus A. These dust lanes are so thick they almost completely obscure the galaxy's center in visible light. This is particularly unusual as Cen A's red stars and round shape are characteristic of a giant elliptical galaxy, a galaxy type usually low in dark dust. Cen A, also known as NGC 5128, is also unusual compared to an average elliptical galaxy because it contains a higher proportion of young blue stars and is a very strong source of radio...

A relic from long before the age of supercomputers, the 169-year-old math strategy called the Jacobi iterative method is widely dismissed today as too slow to be useful. But thanks to a curious, numbers-savvy Johns Hopkins engineering student and his professor, it may soon get a new lease on life. With just a few modern-day tweaks, the researchers say they've made the rarely used Jacobi method work up to 200 times faster. The result, they say, could speed up the performance of computer simulations used in aerospace design, shipbuilding, weather and climate modeling, biomechanics and other engineering tasks. Their paper...

Explanation: To see a vista like this takes patience, hiking, and a camera. Patience was needed in searching out just the right place and waiting for just the right time. A short hike was needed to reach this rugged perch above a secluded cove in Julia Pfeiffer Burns State Park in California, USA. And a camera was needed for the long exposure required to bring out the faint light from stars and nebulae in the background Milky Way galaxy. Moonlight illuminated the hidden beach and inlet behind nearby trees in the above composite image taken last month. Usually obscured McWay...

New solar theory predicts imminent global cooling To recap — using an optimal Fourier Transform, David Evans discovered a form of notch filter operating between changes in sunlight and temperatures on Earth. This means there must be a delay — probably around 11 years. This not only fitted with the length of the solar dynamo cycle, but also with previous independent work suggesting a lag of ten years or a correlation with the solar activity of the previous cycle. The synopsis then is that solar irradiance (TSI) is a leading indicator of some other effect coming from the Sun...

The Solar Series: I Background   |  II: The notch filter  |  III: The delay  |  IV: A new solar force?  |  V: Modeling the escaping heat.  |  VI: The solar climate model   |  VII — Hindcasting (You are here)   | VIII — PredictionsAll models are wrong, some are useful. That’s how all modelers speak (except perhaps some climate scientists).The barriers to making a good climate model are many. The data is short, noisy, adjusted, and many factors are simultaneously at work, some not well described yet. Climate modeling is in its infancy, yet billions of dollars rests...

The University of Maryland physicist believes the delay could have been because the light was in fact slowed as it travelled due to something known as 'vacuum polarisation'. During this phenomenon, photons break down to something known as ‘positrons’ and electrons for a split second. before combining together again. When they split, quantum mechanics creates a gravitational potential between the pair of ‘virtual’ particles. Dr Franson argues that the process might have a gradual impact on the speed of the photon, meaning that over 168,000 light years, the photons may have suffered a near five-hour delay. If the physicist is...

Explanation: Orion's belt runs just along the horizon, seen through Earth's atmosphere and rising in this starry snapshot from low Earth orbit on board the International Space Station. The belt stars, Alnitak, Alnilam, and Mintaka run right to left and Orion's sword, home to the great Orion Nebula, hangs above his belt, an orientation unfamiliar to denizens of the planet's northern hemisphere. That puts bright star Rigel, at the foot of Orion, still higher above Orion's belt. Of course the brightest celestial beacon in the frame is Sirius, alpha star of the constellation Canis Major. The station's Destiny Laboratory module...

Explanation: June 24th marked the first full Martian year of the Curiosity Rover's exploration of the surface of the Red Planet. That's 687 Earth days or 669 sols since its landing on August 5, 2012. To celebrate, consider this self-portrait of the car-sized robot posing next to a rocky outcrop dubbed Windjana, its recent drilling and sampling site. The mosaicked selfie was constructed with frames taken this April and May using the rover's Mars Hand Lens Imager (MAHLI), intended for close-up work and mounted at the end of the rover's robotic arm. The MAHLI frames used exclude sections that show...

In April, we reported that Ceres and Vesta, the largest and brightest asteroids respectively, were speeding through Virgo in tandem. Since then both have faded, but the best is yet to come. Converging closer by the day, on July 5, the two will make rare close pass of each other when they’ll be separated by just 10 minutes of arc or the thickness of a fat crescent moon. ... Both asteroids are still within range of ordinary 35mm and larger binoculars; Vesta is easy at magnitude +7 while Ceres still manages a respectable +8.3. From an outer suburban or rural...

So why ask the question, are physicists constructing a Rube Goldberg device? Our present understanding of the Universe stands upon what is called “the Standard Model” of Cosmology. At the Royal Astronomical Society meeting this week, the discussions underfoot could be revealing a Standard Model possibly in a state of collapse or simply needing new gadgets and mechanisms to remain the best theory of everything. Also this week, new data further supports the discovery of the Higg’s Boson by the Large Hadron Collider in 2012, the elementary particle whose existence explains the mass of fundamental particles in nature and that...

Explanation: Early morning risers were treated to a beautiful conjunction of Venus and waning Crescent Moon on June 24, captured in this seaside photo near Belmar, New Jersey, USA, planet Earth. The serene celestial pairing is seen above the Atlantic Ocean horizon as the eastern sky grows brighter with dawn's early light. Wispy, scattered clouds appear in silhouette. But the exposure also reveals the night side of the lunar orb in the arms of the sunlit crescent. That shadowed part of the Moon, with hints of the smooth, dark lunar seas or maria, is illuminated by Earthshine, sunlight reflected from...

Explanation: These are galaxies of the Hercules Cluster, an archipelago of island universes a mere 500 million light-years away. Also known as Abell 2151, this cluster is loaded with gas and dust rich, star-forming spiral galaxies but has relatively few elliptical galaxies, which lack gas and dust and the associated newborn stars. The colors in this remarkably deep composite image clearly show the star forming galaxies with a blue tint and galaxies with older stellar populations with a yellowish cast. The sharp picture spans about 3/4 degree across the cluster center, corresponding to over 6 million light-years at the cluster's...

The universe shouldn't exist — at least according to a new theory. Modeling of conditions soon after the Big Bang suggests the universe should have collapsed just microseconds after its explosive birth, the new study suggests."During the early universe, we expected cosmic inflation — this is a rapid expansion of the universe right after the Big Bang," said study co-author Robert Hogan, a doctoral candidate in physics at King's College in London. "This expansion causes lots of stuff to shake around, and if we shake it too much, we could go into this new energy space, which could cause the...

Explanation: What flowers in this field of dark star dust? The Iris Nebula. The striking blue color of the Iris Nebula is created by light from the bright star SAO 19158 reflecting off of a dense patch of normally dark dust. Not only is the star itself mostly blue, but blue light from the star is preferentially reflected by the dust -- the same affect that makes Earth's sky blue. The brown tint of the pervasive dust comes partly from photoluminescence -- dust converting ultraviolet radiation to red light. Cataloged as NGC 7023, the Iris Nebula is studied frequently because...

Explanation: Are lasers from giant telescopes being used to attack the Galactic center? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some sky locations, Earth atmosphere-induced fluctuations in starlight can indicate how the air mass over a telescope is changing, but many times no bright star exists in the direction where atmospheric information is needed. In these cases, astronomers create an artificial star where they need it -- with a laser. Subsequent observations of the artificial laser guide star can reveal information so detailed about the blurring effects of the...

The summer astronomical action heats up this week, as the waning crescent Moon joins the inner planets at dawn. This week’s action comes hot on the tails of the northward solstice which occurred this past weekend, which fell on June 21st in 2014, marking the start of astronomical summer in the northern hemisphere and winter in the southern. This also means that the ecliptic angle at dawn for mid-northern latitude observers will run southward from the northeast early in the morning sky. And although the longest day was June 21st, the earliest sunrise from 40 degrees north latitude was June...

Open Science live — The story so far: Dr David Evans is building the O-D notch-delay solar model. It’s a much simpler big-picture approach than Global Climate Coupled Models. They use an ambitious bottom-up system where the models add up every small aspect in every small cell of the Earth’s climate atmosphere and oceans and try to predict everything, but the trap is the errors — small errors in 10,000 calculations add up to big-mush. David’s approach is top-down. He looks at the whole system from the outside, and doesn’t try to understand or predict each individual part. It’s a...

has apparently let slip the sex of her unborn grandchild after referring to the baby as “him” during an interview. The former First Lady, New York senator and possible 2016 presidential candidate will become a grandmother in the autumn, when daughter Chelsea is due to give birth to her first child. Asked what hopes she had for the baby, Mrs Clinton told the Observer she wanted the child to feel: “optimistic, positive, can-do. That it was really up to him.” Following her apparent slip of the tongue, she insisted, however, that she was just using the male pronoun to cover...

Explanation: Are Saturn's auroras like Earth's? To help answer this question, the Hubble Space Telescope and the Cassini spacecraft monitored Saturn's South Pole simultaneously as Cassini closed in on the gas giant in January 2004. Hubble snapped images in ultraviolet light, while Cassini recorded radio emissions and monitored the solar wind. Like on Earth, Saturn's auroras make total or partial rings around magnetic poles. Unlike on Earth, however, Saturn's auroras persist for days, as opposed to only minutes on Earth. Although surely created by charged particles entering the atmosphere, Saturn's auroras also appear to be more closely modulated by the...

About 10 pm, WNW in the sky from central Jersey, moving right to left, split trail, dimming and brightening, biggest one I've ever seen. Probably visible in Eastern PA also.