Astronomy Picture of the Day

2011-03-02 Markus Noller

What's California doing in space? Drifting through the Orion Arm of the spiral Milky Way Galaxy, this cosmic cloud by chance echoes the outline of California on the west coast of the United States. Our own Sun also lies within the Milky Way's ...

2011-03-01

What's happening outside the space station? A space shuttle has docked. Five days ago, the space shuttle Discovery was launched to the International Space Station, carrying six crew members and the large Leonardo Multi Purpose Logistics Module. ...

2011-02-28 Luca Vanzella

What's hovering between those buildings? The Moon. The above image was taken two weeks ago as the full Snow Moon started to rise above Edmonton, Alberta, Canada. The odd coincidence between the angular size of the far distant Moon and the ...

2011-02-27

What lies at the bottom of Hyperion's strange craters? Nobody's sure. To help find out, the robot Cassini spacecraft now orbiting Saturn swooped past the sponge-textured moon in 2005 and 2010 and took images of unprecedented detail. An image ...

2011-02-26 Stephen Leshin

This colorful cosmic skyscape features a peculiar system of galaxies cataloged as Arp 227 some 100 million light-years distant. Swimming within the boundaries of the constellation Pisces, Arp 227 consists of the two galaxies prominent on the ...

2011-02-25

Grand spiral galaxies often seem to get all the glory. Their young, blue star clusters and pink star forming regions along sweeping spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too, like NGC 4449, about ...

2011-02-24 Adam Block

South of the large star-forming region known as the Orion Nebula, lies bright blue reflection nebula NGC 1999. Also at the edge of the Orion molecular cloud complex some 1,500 light-years distant, NGC 1999's illumination is provided by the ...

2011-02-23

If you looked out from the center of the Solar System, what would you see? Nearly such a view was taken recently from the MESSENGER spacecraft currently orbiting the Sun from the distance of Mercury. The Sun's planets all appear as points of ...

2011-02-21

What's visible in the night sky during this time of year? To help illustrate the answer, a beautiful land, cloud, and skyscape was captured earlier this month over Neuchâtel, Switzerland. Visible in the foreground were the snow covered cliffs of ...

2011-02-20

What's happened to these clouds? Normal cloud bottoms are flat because moist warm air that rises and cools will condense into water droplets at a very specific temperature, which usually corresponds to a very specific height. After water ...