Astronomy Picture of the Day

dmp

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http://antwrp.gsfc.nasa.gov/apod/ap060509.html

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A new rock slab is growing at more than one meter a day on the Mt. St. Helens volcano in Washington, USA. The rock slab, growing since last November, now extends about 100 meters out from one of the volcano's craters.

More at link.
 
Granny says is prob'ly where Uncle Ferd lil' green friends come from...

Potentially Earth-like Planet Found 14 Light Years Away
December 17, 2015 - Australian astronomers say they've found the closest potentially habitable planet to Earth outside the solar system. And it's only 14 light years away!
The researchers from the University of New South Wales say planet Wolf 1061c is believed to be four times the mass of Earth. It is one of three planets that were discovered around a red dwarf star known as Wolf 1061. "It is a particularly exciting find because all three planets are of low enough mass to be potentially rocky and have a solid surface, and the middle planet, Wolf 1061c, sits within the 'Goldilocks' zone where it might be possible for liquid water -- and maybe even life -- to exist," said lead author Duncan Wright of UNSW. "It is fascinating to look out at the vastness of space and think a star so very close to us -- a near neighbor -- could host a habitable planet,” he said. Other planets have been found closer to Earth, but they are not “remotely habitable” said Wright.

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This is a simulation of the orbital configuration of the Wolf 1061 system. Wolf 1061 is an inactive red dwarf star, smaller and cooler than our sun, 14 light years away.​

The researchers said in a news release the three newly detected planets orbit the relatively cool and stable star Wolf 1061 every five, 18 and 67 days. Small, rocky planets are believed to be common in our galaxy, but most of the exoplanets discovered so far are hundreds or thousands of light years away.

One exception, researchers note, is Gliese 667Cc, which is 22 light years away from Earth. It, too, orbits a red dwarf star, but does so every 28 days and is more than four times Earth's mass. "The close proximity of the planets around Wolf 1061 means there is a good chance these planets may pass across the face of the star. If they do, then it may be possible to study the atmospheres of these planets in future to see whether they would be conducive to life," said team member Rob Wittenmyer. The discovery will be published in a future edition of Astrophysical Journal Letters.

Here's a video about the discovery:

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A Blast of Gamma Rays from Halfway Across the Universe Detected
December 16th, 2015 - Back in April 2015, a surge of high-powered gamma rays from half-way across the universe crashed into Earth’s atmosphere.[/b]
But, according to the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, the burst of gamma rays didn’t put any of us in danger and produced no noticeable effects since the high-energy rays are blocked by Earth’s atmosphere. Astronomers, using space and ground based telescopes found that this burst of powerful emissions came from a unique and active galaxy 7.6 billion light years from Earth. The galaxy, known as PKS 1441+25, is actually a rare, compact and very bright mass of energy and light called a blazar. The blazar’s twin powerful and opposite directed jets of plasma are driven at near light speed by a supermassive black hole located in the center of the galaxy.

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This artist’s conception shows a blazar – the core of an active galaxy powered by a supermassive black hole.​

As a black hole sucks in a variety of matter, such as dust, gas and even a star, it forms a surrounding high-energy accretion disk of elementary particles such as photons, electrons and positrons. Friction is generated as these subatomic particles, from the accretion disk, gets pulled into the black hole’s point of no return (event horizon). The friction heats tiny bits of material into a plasma. The plasma combines with the black hole’s revolving magnetic field to form the blazar’s jets. While scientists are still arguing over the exact processes that generate the gamma-ray emissions from the jets, the researchers say their findings will provide valuable clues. April’s gamma ray burst was observed and studied over a number of different wavelengths with telescopes such as NASA’s Fermi Gamma Ray and Swift space telescopes and the Very Energetic Radiation Imaging Telescope Array System (VERITAS) in Arizona.

The astronomers said their multi-wavelength observations of this rare phenomena provided them with valuable insight into where such gamma rays are produced, the various physical processes that occur near the black hole, as well as a unique look into the distant galaxy. The researchers figured that the region where the burst of gamma rays originated is probably about five light years from the black hole, which is much further than they expected. They also found that the size of the gamma ray emitting region was around a third of a light year across, which was bigger than what is normally observed in an active galaxy. The astronomer’s findings will be published in Astrophysical Journal Letters, which are currently available online.

A Blast of Gamma Rays from Halfway Across the Universe Detected « Science World
 
Hubble spots dark vortex on Neptune...
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Hubble locates new dark spot on Neptune
June 23, 2016 - The last several Neptune vortices seen by astronomers have exhibited a wide range of sizes and shapes.
There's a new dark spot on Neptune, the farthest planet from the sun. Astronomers recently confirmed the presence of a dark vortex spinning across the planet's atmosphere after examining imagery collected by the Hubble Space Telescope last month. It's the first Neptune vortex discovered since 1994.

The high pressure system is accompanied by bright companion clouds. Researchers believe the clouds are formed as the vortex pushes ambient air higher into the atmosphere, forcing gases to freeze into methane ice crystals. "Dark vortices coast through the atmosphere like huge, lens-shaped gaseous mountains," Mike Wong, a researcher astronomer at the University of California, Berkeley, said in a news release. "And the companion clouds are similar to so-called orographic clouds that appear as pancake-shaped features lingering over mountains on Earth."

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Wong led the investigation of Hubble data that yielded the discovery of the new dark spot. Jupiter hosts similar cyclone-like disturbances, but the gas giant's vortices are more uniform and sometimes persist, slowly evolving, for decades. Previous studies have proven Neptune's vortices to be a permanent feature, but the disturbances are shorter-lived.

The last several Neptune vortices seen by astronomers have exhibited a wide range of sizes and shapes, and have proven to be relatively unstable -- wandering north and south, speeding up and slowing down. Scientists hope further monitoring of Neptune's vortices will illuminate how they originate and the factors that influence their fluctuations.

Hubble locates new dark spot on Neptune

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‘Dark Vortex’ Spotted on Neptune
June 24, 2016 - The vortex is about the same size as the US
Astronomers have spotted a “dark vortex” swirling in Neptune’s atmosphere. Using high resolution images captured in May by the Hubble Space Telescope, researchers say the vortex is about the size of the continental United States.

The vortex is a high pressure system and is accompanied by bright clouds. In 2015, astronomers spotted clouds and later a dark spot nearby. The May 2016 images confirmed the presence of the vortex. "Dark vortices coast through the atmosphere like huge, lens-shaped gaseous mountains," said University of California at Berkeley research astronomer Mike Wong. "And the companion clouds are similar to so-called orographic clouds that appear as pancake-shaped features lingering over mountains on Earth." Vortices on Neptune have been spotted before. In 1989, the Voyager 2 spacecraft saw one, and in 1994, Hubble pinpointed one.

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A dark vortex was spotted on Neptune.​

Astronomers say the vortices “have exhibited surprising diversity over the years, in terms of size, shape, and stability (they meander in latitude, and sometimes speed up or slow down).” They also have relatively short lifespans compared to anticyclones seen on Jupiter, which “evolve over decades. Further study should yield a better understanding about how vortices develop, what causes them to move and how they interact with the environment, researchers said. Neptune is roughly 4.3 billion kilometers from the Sun, and it takes 165 Earth years to make one orbit of the sun.

‘Dark Vortex’ Spotted on Neptune
 

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