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.

2007 August 7
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Old Faithful Below a Yellowstone Sky
Credit & Copyright: Wally Pacholka (

Explanation: You don't have to be at Yellowstone to see a sky this beautiful, but it helps. Only at Yellowstone National Park in Wyoming, USA, would you see the picturesque foreground of the famous Old Faithful Geyser erupting in front an already picturesque sky. Old Faithful Geyser, visible in the foreground, is seen propelling a stream of hot water over 30 meters in the air. This happens predictably for a few minutes about every 90 minutes. Also predictable are the brightest orbs that populate the nighttime sky, although those visible at any one time keep changing. Visible far in the background sky of this mid-July image are the plane of our Milky Way Galaxy on the left, and the bright planet Jupiter on the right. Jupiter is the brightest celestial object in the entire image. Old Faithful has been erupting at least since the late 1800s.

Tomorrow's picture: phoenix rising

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