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Comment by Michel on June 14, 2012 at 11:24am

Would there be any such thing as a "night sky" in the core of that cluster? I can't begin to imagine the turbulence we'd get with a hundred star systems between here and Proxima Centauri...

Comment by doone on June 14, 2012 at 8:04am

M13: The Great Globular Cluster in Hercules 
Image Credit & Copyright: Martin Pugh

Explanation: In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent." Of course, M13 is now modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the northern sky. Telescopic views reveal the spectacular cluster's hundreds of thousands of stars. At a distance of 25,000 light-years, the cluster stars crowd into a region 150 light-years in diameter, butapproaching the cluster core upwards of 100 stars could be contained in a cube just 3 light-years on a side. For comparison, the closest star to the Sun is over 4 light-years away. Along with the cluster's dense core, the outer reaches of M13 are highlighted in this sharp color image. The cluster's evolved red and blue giant stars show up in yellowish and blue tints.

Comment by Michel on June 12, 2012 at 10:33am

Stardust bunnies!

Comment by doone on June 12, 2012 at 7:11am

Thackeray's Globules 
Credit & Copyright: T. Rector (U. Alaska Anchorage), & N.S. van der Bliek (NOAO/AURA/NSF)

Explanation: These are larger dust bunnies than you will find under your bed. Situated in rich star fields and glowing hydrogen gas, these opaque clouds of interstellar dust and gas are so large they might be able to form stars. Their home is known as IC 2944, a bright stellar nursery located about 5,900 light years away toward the constellation of Centaurus. The largest of these dark globules, first spotted by South African astronomer A. D. Thackeray in 1950, is likely two separate but overlapping clouds, each more than one light-year wide. Along with other data, the above representative color image from the 4-m Blanco telescope at Cerro Tololo, Chile indicates that Thackeray's globules are fractured and churning as a result of intense ultraviolet radiation from young, hot stars already energizing and heating the bright emission nebula. These and similar dark globules known to be associated with other star forming regions may ultimately be dissipated by their hostile environment -- like cosmic lumps of butter in a hot frying pan.

Comment by doone on June 11, 2012 at 6:17am

2012 June 11 

A Venus Transit Music Video from SDO 
Credit: Solar Dynamics Observatory, SVS, GSFC, NASA; Music: Requiem for a Dream (Clint Mansell)

Explanation: What's that black dot moving across the Sun? Venus. Possibly the clearest view of Venus crossing in front of the Sun last week was from Earth orbit. The Solar Dynamics Observatory obtained an uninterrupted vista recording it not only in optical light but also in bands of ultraviolet light. Pictured above is a composite movie of the crossing set to music. Although the event might prove successful scientifically for better determining components of Venus' atmosphere, the event surely proved successful culturally by involving people throughout the world in observing a rare astronomical phenomenon. Many spectacular images of this Venus transit from around (and above) the globe are being proudly displayed.

Comment by Michel on June 10, 2012 at 11:14am

The Venus pic is now my new wallpaper, thanks doone =)

Perhaps the NASA could do a Kickstarter project with these two telescopes. Who knows what kind of money they'd get?

Comment by doone on June 10, 2012 at 10:03am

Two New Hubble-Quality Telescopes Gifted to NASA 
Credit: NASA

Explanation: What if you were given a new Hubble telescope for free? How about two? The astronomical community is abuzz with just this opportunity as the US National Reconnaissance Office has unexpectedly transferred ownership of two space-qualifiedHubble-quality telescopes to NASA. The usefulness of these telescopes in addressing existing science priorities has begun, but preliminary indications hold that even one of these telescope could be extremely useful in searching for extrasolar planets as well asdistant galaxies and supernovas that could better explore the nature of dark energy. Although they start out as free, making even one telescope operational and fitting it with useful cameras would be quite expensive, so NASA is being decidedly careful about how to fit these new telescopes into its existing budget. Pictured above, the original Hubble Space Telescope floats high above the Earth during a servicing mission in 2002.

Prefer Spanish?: Follow APOD's new Facebook feed "Universo" 

Comment by doone on June 9, 2012 at 10:55am

Venus at the Edge 
Image Credit: JAXA, NASA, Lockheed Martin

Explanation: As its June 6 2012 transit begins Earth's sister planet crosses the edge of the Sun in this stunning view from the Hinode spacecraft. The timing of limb crossings during the rare transits was used historically to triangulate the distance to Venus and determine a value for the Earth-Sun distance called the astronomical unit. Still, modern space-based views like this one show the event against an evocative backdrop of the turbulent solar surface with prominences lofted above the Sun's edge by twisting magnetic fields. Remarkably, the thin ring of light seen surrounding the planet's dark silhouette is sunlight refracted by Venus' thick atmosphere.

Comment by doone on June 8, 2012 at 10:15pm

Kinetic Sculpture of The Universe

Jun. 8, 2012

Comment by doone on June 8, 2012 at 7:57am

When Venus Rises with the Sun 
Image Credit & Copyright: Emil Ivanov

Explanation: This dramatic telephoto view across the Black Sea on June 6 finds Venus rising with the Sun, the planet in silhouette against a ruddy and ragged solar disk. Of course, the reddened light is due to scattering in planet Earth's atmosphere and the raretransit of Venus didn't influence the strangely shaped and distorted Sun. In fact, seeing the Sun in the shape of an Etruscan Vase is relatively common, especially compared to Venus transits. At sunset and sunrise, the effects of atmospheric refraction enhanced by long, low, sight lines and strong atmospheric temperature gradients produce the visual distortions and mirages. That situation is often favored by a sea horizon.

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