Astronomy Picture of the Day for February 11

Astronomy Picture of the Day

Discover the cosmos!Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2012 January 17
See Explanation.  Clicking on the picture will download the highest resolution version available.

IC 2118: The Witch Head Nebula
Image Credit & Copyright: Gimmi Ratto & Davide Bardini (Collecting Photons) 

 

Explanation: Double, double toil and trouble; Fire burn, and cauldron bubble — maybe Macbeth should have consulted the Witch Head Nebula. This suggestively shaped reflection nebula is associated with the bright star Rigel in the constellation Orion. More formally known as IC 2118, the Witch Head Nebula glows primarily by light reflected from bright star Rigel, located just below the lower edge of the above image. Fine dust in the nebula reflects the light. The blue color is caused not only by Rigel’s blue color but because the dust grains reflect blue light more efficiently than red. The same physical process causes Earth’s daytime sky to appear blue, although the scatterers in Earth’s atmosphere are molecules of nitrogen and oxygen. The nebula lies about 1000 light-years away.

Astronomy Picture of the Day for Jan. 23

Astronomy Picture of the Day

Discover the cosmos!Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2012 January 23
See Explanation.Moving the cursor over the image will bring up an annotated version.Clicking on the image will bring up the highest resolution versionavailable.

Deep Orion Over the Canary Islands
Image Credit & Copyright: Juan Carlos Casado (TWAN) 

Explanation: Which attracts your eye more — the sky or the ground? On the ground are rocky peaks in Teide National Park on Tenerife Island of the Spanish Canary Islands off the northwestern coast of Africa. The volcanic landscape features old island summits and is sometimes used as a testbed for instruments on future Martian rovers. The lights of a nearby hotel shine on the far left. Storm clouds are visible on the horizon, artificially strutted from multiple exposures. Dividing the sky, across the middle of the above deep image, is the vertical band of the Milky Way Galaxy. The red circle on the right is Barnard’s Loop, near the center of which are the famous belt stars of the constellation Orion. Soon after the above image was taken, during an evening earlier this year, storm clouds rolled across, and indoor locations began to attract eyes the most.