Astronomy Picture of the Day

photo The Orion You Can Almost See

The Orion You Can Almost See

Do you recognize this constellation? Although it is one of the most recognizable star groupings on the sky, this is a more full Orion than you can see -- an Orion only revealed with long exposure digital camera imaging and post-processing. Here ...

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photo Animation: Spiral Disk around a Black Hole

Animation: Spiral Disk around a Black Hole

What would it look like to orbit a black hole? Many black holes are surrounded by swirling pools of gas known as accretion disks. These disks can be extremely hot, and much of the orbiting gas will eventually fall through the black hole's event ...

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photo Lenticular Clouds over Mount Etna

Lenticular Clouds over Mount Etna

What's happening above that volcano? Although Mount Etna is seen erupting, the clouds are not related to the eruption. They are lenticular clouds formed when moist air is forced upwards near a mountain or volcano. The surreal scene was captured ...

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photo Human as Spaceship

Human as Spaceship

You are a spaceship soaring through the universe. So is your dog. We all carry with us trillions of microorganisms as we go through life. These multitudes of bacteria, fungi, and archaea have different DNA than you. Collectively called your ...

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photo 1901 Photograph: The Orion Nebula

1901 Photograph: The Orion Nebula

By the turn of the 20th century advances in photography contributed an important tool for astronomers. Improving photographic materials, long exposures, and new telescope designs produced astronomical images with details not visible at the ...

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photo The Elephant's Trunk Nebula in Cepheus

The Elephant's Trunk Nebula in Cepheus

Like an illustration in a galactic Just So Story, the Elephant's Trunk Nebula winds through the emission nebula and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. Also known as vdB 142, the cosmic elephant's ...

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photo The Perseids and the Plough

The Perseids and the Plough

Despite interfering moonlight, many denizens of planet Earth were able to watch this year's Perseid meteor shower. This pastoral scene includes local skygazers admiring the shower's brief, heavenly flashes in predawn hours near peak activity on ...

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photo Saturn Behind the Moon

Saturn Behind the Moon

What's that next to the Moon? Saturn. In its monthly trip around the Earth -- and hence Earth's sky -- our Moon passed nearly in front of Sun-orbiting Saturn earlier this week. Actually the Moon passed directly in front of Saturn from the ...

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photo Supernova Cannon Expels Pulsar J0002

Supernova Cannon Expels Pulsar J0002

What could shoot out a neutron star like a cannon ball? A supernova. About 10,000 years ago, the supernova that created the nebular remnant CTB 1 not only destroyed a massive star but blasted its newly formed neutron star core -- a pulsar -- out ...

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photo Perseid Meteors over Slovakia

Perseid Meteors over Slovakia

Tonight is a good night to see meteors. Comet dust will rain down on planet Earth, streaking through dark skies during the peak of the annual Perseid Meteor Shower. The featured composite image was taken during last year's Perseids from the ...

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