Over its lifetime, NASA's Hubble Space Telescope has captured many stunning images. Among the most memorable is this edge-on mosaic of the Sombrero galaxy. With its relatively high brightness magnitude and at a distance of 28 million light-years from Earth, Messier 104, as Sombrero is more formally known, is easily viewed through a small telescope.

The intricately shaped Cat's Eye nebula is formed from concentric gas bubbles and high-speed jets ejected from the outer layers of a dying star. One theory is that the gases were released at 1,500-year intervals, giving the nebula its layered appearance.

Pillars of hydrogen gas and dust streaming from the Eagle nebula give birth to new stars. The largest pillar (left) is an estimated four light-years long and, like its neighbors, is being bombarded by ultraviolet starlight that boils away gas on its surface and exposes the embryonic stars forming in its interior. The stepped shape of this image is caused by the design of Hubble's Wide Field and Planetary Camera 2.

This full-color map of Mars was created with Hubble images captured when the planet was at its closest approach to Earth. More southerly regions are not visible because the north of the red planet was tilted toward Earth

 A pulse of light emitted in 2002 from a red supergiant star called V838 Monocerotis illuminates a cloud of interstellar dust. The dramatic whorls around the central star are trillions of miles across and were unknown to scientists until Hubble snapped this image in 2004.

Streams of charged particles blasted from the sun collide with Saturn's magnetic field, creating an aurora on the planet's south pole. Unlike Earth's relatively short-lived auroras, Saturn's can last for days. Scientists combined ultraviolet images of the auroras, taken by Hubble over a period of days, with visible-light images of the ringed planet. In this view the aurora appears blue because of the ultraviolet camera, but a Saturn-based observer would see red light flashes.

A Hubble image of supernova 1987A shows a glowing wheel of debris ejected by a dying star some 20,000 years before it exploded. The ring, described as "cosmic pearls," is being illuminated by a shockwave of material emitted by the massive supernova explosion. The two bright spots outside the ring are stars in the Large Magellanic Cloud.

Two galaxies, known collectively as Arp 87, distort as their gravitational fields interact. The larger of the pair, NGC 3808, is drawing stars, gas, and dust from the smaller. Both galaxies are spiral-shaped and located about 300 million light-years from Earth in the constellation Leo.

 A face-on view of the Messier 74 galaxy shows billions of stars forming within its spiral arms. The clusters of blue are young stars, and the pink areas indicate concentrations of ionized hydrogen. Messier 74 is home to about a hundred billion stars, slightly fewer than the Milky Way has, and sits near the constellation Pisces some 32 million light-years away.