A density map of part of the Milky Way disk, constructed from IPHAS data. The axes show galactic latitude and longitude, coordinates that relate to the position of the centre of the galaxy. The mapped data are the counts of stars detected in i, the longer (redder) wavelength broad band of the survey, down to a faint limit of 19th magnitude. Although this is just a small section of the full map, it portrays in exquisite detail the complex patterns of obscuration due to interstellar dust. Credit: Hywel Farnhill, University of Hertfordshire.

A density map of part of the Milky Way’s disk. The axes show galactic latitude and longitude, coordinates that relate to the position of the center of the galaxy. Credit: Hywel Farnhill, University of Hertfordshire.

On the darkest of nights, thousands of stars are sprinkled across the celestial sphere above us. Or, to be exact, there are 9,096 stars observable across the entire sky. Divide that number in half, and there are 4,548 stars (give or take a few) visible from horizon to horizon.

But this number excludes the glowing band stretching across the night sky, the Milky Way. It’s the disk of our own galaxy, a system stretching 100,000 light-years across. The naked eye is unable to distinguish individual specks of light, but the Isaac Newton Telescope (INT) on La Palma in the Canary Islands has recently charted 219 million separate stars in this disk alone.

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Aurora over a Glacier Lagoon. Credit and copyright: James Woodend, UK

Aurora over a Glacier Lagoon. Credit and copyright: James Woodend, UK

The winners of the 2014 “Astronomy Photographer of the Year” competition have been announced at the Royal Observatory in Greenwich England, and British photographer James Woodend’s gorgeous image of the aurora dancing across the Icelandic night sky was named the overall winner. This is the sixth year for the competition, which is run by the ROG and the Sky at Night Magazine.

“Every year the competition becomes more and more challenging to judge and we’re always astounded by the skill of the photographers,” said Dr. Maggie Aderin-Pocock, a presenter on The Sky at Night and one of the judges for the competition. “The Deep Space category, where the entrants have been able to capture such amazing details of objects light-years away and are almost on par with images taken by the Hubble Space Telescope, never fails to impress.”

See more gorgeous images and a list of the winners in the various categories below:
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"I never imagined that flying to space would give me a different view of our entire galaxy," tweeted Expedition 41 astronaut Alexander Gerst from the International Space Station in September 2014. Credit: Alexander Gerst / Twitter

“I never imagined that flying to space would give me a different view of our entire galaxy,” tweeted Expedition 41 astronaut Alexander Gerst from the International Space Station in September 2014. Credit: Alexander Gerst / Twitter

While NASA often speaks about the power of Earth observation from the International Space Station, the picture above from one of the astronauts on board now shows something else — you can get an awesome view of the Milky Way.

With the view unobscured by the atmosphere, the picture from Expedition 41 European astronaut Alexander Gerst shows that his perch on the ISS is pretty amazing. We wonder how it compares to some of the desert or mountaintop observatories here on Earth! And there are astronomical experiments on board, such as this one that may have found dark matter.

Below we’ve handpicked some of the best recent pictures from Gerst and NASA astronaut Reid Wiseman, a crewmate, as they take in the wonder of our planet and the universe.

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This Exoplanet Has Prematurely Aged its Star

by Shannon Hall on September 18, 2014

 X-ray: NASA/CXC/SAO/I.Pillitteri et al; Optical: DSS; Illustration: NASA/CXC/M.Weiss

Optical and X-ray images of the star WASP 18. X-ray Credit: NASA / CXC / SAO / I.Pillitteri et al; Optical Credit: DSS; Illustration Credit: NASA / CXC / M.Weiss

Hot young stars are wildly active, emitting huge eruptions of charged particles form their surfaces. But as they age they naturally become less active, their X-ray emission weakens and their rotation slows.

Astronomers have theorized that a hot Jupiter — a sizzling gas giant circling close to its host star — might be able to sustain a young star’s activity, ultimately prolonging its youth. Earlier this year, two astronomers from the Harvard-Smithsonian Center for Astrophysics tested this hypothesis and found it true.

But now, observations of a different system show the opposite effect: a planet that’s causing its star to age much more quickly.

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Sandy Ridges Pose A Mystery For Future Martian Beach Vacations

by Elizabeth Howell on September 18, 2014

A September 2014 image from the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter showing transverse aeolian ridges. Credit: NASA/JPL/University of Arizona

A September 2014 image from the High Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter showing transverse aeolian ridges. Credit: NASA/JPL/University of Arizona

What are these thick dune-like features on Mars, and how were they formed? Scientists are still trying to puzzle out these ridges, which you can see above in a more tropical region of the Red Planet called Iapygia, which is south of Syrtis Major. The thick ridges were captured from orbit by the Mars Reconnaissance Orbiter’s High Resolution Imaging Science Experiment (HiRISE), and we’ve included some more intriguing pictures below the jump.

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