Astronomy compels the soul to look upwards and leads us from this world to another.

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Halo of NGC 6164 

Measuring Atmospheric Climate Change: NASA’s Carbon Counting Observatory Collects “First Light”

NASA’s CO2, greenhouse gas satellite has taken its first look at Earth’s carbon dioxide. Learn about this project, and what we can learn from it, at http://bit.ly/1s2sAwM

NASA’s WISE findings poke hole in black hole ‘doughnut’ theory

A survey of more than 170,000 supermassive black holes, using NASA’s Wide-field Infrared Survey Explorer (WISE), has astronomers reexamining a decades-old theory about the varying appearances of these interstellar objects.

The unified theory of active, supermassive black holes, first developed in the late 1970s, was created to explain why black holes, though similar in nature, can look completely different. Some appear to be shrouded in dust, while others are exposed and easy to see.
The unified model answers this question by proposing that every black hole is surrounded by a dusty, doughnut-shaped structure called a torus. Depending on how these “doughnuts” are oriented in space, the black holes will take on various appearances. For example, if the doughnut is positioned so that we see it edge-on, the black hole is hidden from view. If the doughnut is observed from above or below, face-on, the black hole is clearly visible.
However, the new WISE results do not corroborate this theory. The researchers found evidence that something other than a doughnut structure may, in some circumstances, determine whether a black hole is visible or hidden. The team has not yet determined what this may be, but the results suggest the unified, or doughnut, model does not have all the answers.
Every galaxy has a massive black hole at its heart. The new study focuses on the “feeding” ones, called active, supermassive black holes, or active galactic nuclei. These black holes gorge on surrounding gas material that fuels their growth.
With the aid of computers, scientists were able to pick out more than 170,000 active supermassive black holes from the WISE data. They then measured the clustering of the galaxies containing both hidden and exposed black holes — the degree to which the objects clump together across the sky.
If the unified model was true, and the hidden black holes are simply blocked from view by doughnuts in the edge-on configuration, then researchers would expect them to cluster in the same way as the exposed ones. According to theory, since the doughnut structures would take on random orientations, the black holes should also be distributed randomly. It is like tossing a bunch of glazed doughnuts in the air — roughly the same percentage of doughnuts always will be positioned in the edge-on and face-on positions, regardless of whether they are tightly clumped or spread far apart.
But WISE found something totally unexpected. The results showed the galaxies with hidden black holes are more clumped together than those of the exposed black holes. If these findings are confirmed, scientists will have to adjust the unified model and come up with new ways to explain why some black holes appear hidden.

Image credit: NASA/JPL-Caltech

The Lagoon Nebula in the constellation Sagittarius 
Image credit: NASA/ESA Hubble Space Telescope

Moonrise Dusk
Saguaro National Park, Arizona, USA | by Beau Rogers

The Dolphin Nebula (Barnard 252)
Located among the incredibly dense star fields of Scorpius lies a beautiful little dark nebula; Barnard 252. There appears to exist very little, if any, information about this striking absorbing cloud, and it has no popular name. Some think it bears a strong resemblance to a jumping dolphin so they call it The Dolphin Nebula.  This interstellar cloud is sufficiently dense to completely block the light from thousands of background stars in the direction towards our galactic centre. These clouds are full of tiny dust particles, each less than a micrometre in size. Optical wavelengths are easily absorbed by this dust and therefore the nebulae appear dark against any background light. However, radio and infrared wavelengths can penetrate the clouds and allow a peek inside where star formation often occurs. Credits: Taken from my observatory in Auckland, New Zealand/From Rolf Olson Astrophotography

M51 Hubble Remix

Hidden Village | by Max Slastnikov

Lighthouse’s Supermoon by mmeida http://ift.tt/1qjKzwF