Astronomy Picture of the Day

2011-12-22 Arne Erisoty

Today the Sun stands still at 05:30 UT. Halting its steady march toward southern declinations and begining its annual journey north, the event is known as a solstice. In the northern hemisphere December's solstice marks the astronomical start of ...

2011-12-21

What's large and blue and can wrap itself around an entire galaxy? A gravitational lens mirage. Pictured above, the gravity of a luminous red galaxy (LRG) has gravitationally distorted the light from a much more distant blue galaxy. More ...

2011-12-20 Angus Lau

NGC 253 is not only one of the brightest spiral galaxies visible, it is also one of the dustiest. Discovered in 1783 by Caroline Herschel in the constellation of Sculptor, NGC 253 lies only about ten million light-years distant. NGC 253 is the ...

2011-12-19 Arman Golestaneh

Some beautiful things begin as grains of sand. Locked in an oyster, a granule grows into an iridescent pearl, lustrous and lovely to behold. While hurtling through the atmosphere at 35 kilometers per second, a generous cosmic sand grain becomes ...

2011-12-18 Hadron

Why do objects have mass? To help find out, Europe's CERN has built the Large Hadron Collider (LHC), the most powerful particle accelerator yet created by humans. Since 2008, the LHC has smashed protons into each other with unprecedented ...

2011-12-17

Like most other sungrazing comets, Comet Lovejoy (C/2011 W3) was not expected to survive its close encounter with the Sun. But it did. This image from a coronograph onboard the sun-staring SOHO spacecraft identifies the still inbound remnants of ...

2011-12-16 Oshin Zakarian

This surreal, wintry scene is a composite picture recorded on December 10 as the Moon rose behind the Zagros Mountains of Iran. A total lunar eclipse was already in progress. The image combines nearly 500 successive frames taken over 1.5 hours ...

2011-12-15 Wang, Letian

The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, it has a circular cross section most easily seen during a lunar eclipse. For example, last Saturday the Full Moon slid across the southern half ...

2011-12-14 Chander Devgun

Our Moon turned red last week. The reason was that during December 10, a total lunar eclipse occurred. The above digitally superimposed image mosaic captured the Moon many times during the eclipse, from before the Moon entered Earth's shadow ...

2011-12-13 Dieter Willasch

Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars. The brightest ...