Astronomy Pictures

A Roll Cloud Over Uruguay

This is a roll cloud. These rare long clouds may form near advancing cold fronts. In particular, a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point, and so form a cloud.

Floral Aurora Corona

Few auroras show this level of detail. Above, a standard digital camera captured a particularly active and colorful auroral corona that occurred in Alberta, Canada. With a shape reminiscent of a flower, the spectacular aurora had an unusually high degree of detail. The vivid green and purple auroral colors are caused by high atmospheric oxygen and hydrogen reacting to a burst of incoming electrons.

Milky Way Galaxy

The Milky Way photographed from Sandras Mountain in Turkey. (Canon EOS 5D digital SLR, 24mm lens at f/2.8, ISO 3200, five 45-second exposures connected side by side)

Jellyfish Nebula

The Jellyfish Nebula is seen to be part of the supernova remnant IC 433, which is approximately 5,000 light-years distant. (4-inch Takahashi FSQ106 refractor, SBIG ST-10XE CCD camera, Sulfur-II/Hydrogen-alpha/Oxygen-III image with exposures of 450, 300, and 90 minutes, respectively)

Blue Moon Eclipse

The International Year of Astronomy 2009 ended with a Blue Moon and a partial lunar eclipse. The New Year's Eve Blue Moon eclipse was visible throughout Europe, Asia, Africa and parts of Alaska, captured in this two exposure composite in cloudy skies over Saint Bonnet de Mure, France.