

What happens when you crash into a comet? That was a question considered by astronomers when they designed the Deep Impact mission, launched in January. On July 4, the Deep Impact spaceship will reach its target, Comet Tempel 1, and fire an impactor at its surface, photographing the result. The remaining crater may tell how Tempel 1 is constructed. If, for example, the comet is an extremely loose pile of debris, the impactor may leave little or no discernable crater. But if the comet's surface is relatively firm, the impactor's ripple may leave quite a large crater. Pictured above is an artist's impression of the initial encounter between the spacecraft and the comet.
This undated photo shows a night view of the Armazones hill in the Chile's Atacama desert, where the world's largest telescope will be built by the European Southern Observatory at a cost over $1 billion.
The M81 galaxy is tilted at an oblique angle on to our line of sight, giving earthlings a 'birds-eye view' of the spiral structure. The galaxy is similar to our Milky Way, but our favorable view provides a better picture of the typical architecture of spiral galaxies. M81 may be undergoing a surge of star formation along the spiral arms due to a close encounter it may have had with its nearby spiral galaxy NGC 3077 and a nearby starburst galaxy (M82) about 300 million years ago. This image combines data from the Hubble Space Telescope, the Spitzer Space Telescope, and the Galaxy Evolution Explorer.
The International Space Station was in position to view the shadow cast by the moon as it moved between Earth and the sun during a solar eclipse on March 29, 2006. This image captures the moon's shadow as it passes over southern Turkey, northern Cyprus, and the Mediterranean Sea.
NASA Dryden's T-38 Talon trainer jet flies over the main base complex at Edwards Air Force Base. Formerly at NASA's Langley Research Center, this Northrop T-38 Talon is now used for mission support and pilot proficiency at the Dryden Flight Research Center.
What would our Milky Way galaxy look like if we could travel outside it and snap a picture? It might look a lot like this image by NASA's Spitzer Space Telescope of a spiral galaxy called NGC 7331 - a virtual twin of our Milky Way.
In this photo taken Saturday, June 26, the European Ariane 5 rocket lifts off in Kourou, French Guiana. The rocket put the payloads of Arabsat-5A and COMS, spacecraft for Korea Aerospace Research Institute of South Korea into Geostationary transfer orbits.
This image of spiral galaxy NGC 3627, also known as Messier 66, was captured by the Spitzer Infrared Nearby Galaxy Survey Legacy Project. NGC 3627 is estimated to be 30 million light-years away, towards the constellation Leo. Astronomers suspect that the galaxy's distorted shape is caused by its ongoing gravitational interactions with its neighbors Messier 65 and NGC 3628. NGC 3627 is another brilliant example of a barred spiral galaxy, the most common type of disk galaxy in the local universe.
This artist's impression released by European Space Agency shows the Automated Transfer Vehicle approaching the International Space Station. The vehicle, named Jules Vernes, arrived at Europe's Spaceport in Kourou, French Guiana, late 31 July 2007.