Images from Space
During the 15 years that the NASA/European Space Agency (ESA) Hubble Space Telescope has orbited the Earth, it has taken three-quarters of a million photos of the cosmos -- images that have awed, astounded and even confounded astronomers and the public alike.
On Monday, April 25, 2005, NASA and ESA released new views of two of the most well-known images Hubble has ever taken: the Eagle Nebula, and spiral galaxy M51, known as the Whirlpool Galaxy. The images, among the largest and sharpest views Hubble has ever taken, were made with the Advanced Camera for Surveys (ACS). The two new images are so incredibly sharp they could be enlarged to billboard size and still retain all of their stunning details.
Scientists used the newer ACS camera to revisit one region of the eerie-looking Eagle Nebula, producing a new image with stunning detail. The image reveals a tall, dense tower of gas being sculpted by ultraviolet light from a group of massive, hot stars.
The soaring tower is 9.5 light-years or about 90 trillion kilometers high, about twice the distance from our Sun to the next nearest star. A torrent of ultraviolet light from a band of massive, hot, young stars [near the top] is eroding the pillar. The dominant colors in the image were produced by gas energized by the star cluster's powerful ultraviolet light. The blue color at the top is from glowing oxygen. The red color in the lower region is from glowing hydrogen. The Eagle Nebula image was taken in November 2004.
The new Whirlpool Galaxy image showcases the spiral galaxy's classic features, from its curving arms, where newborn stars reside, to its yellowish central core that serves as home for older stars. The graceful, winding arms of M51 are actually long lanes of stars and gas laced with dust. This sharpest-ever image, taken in January 2005, illustrates a spiral galaxy's grand design. Some astronomers believe that the Whirlpool's arms are so prominent because of the effects of a close encounter with NGC 5195, the small, yellowish galaxy at the outermost tip of one of the Whirlpool's arms. At first glance, the compact galaxy appears to be tugging on the arm. Hubble's clear view, however, shows that NGC 5195 is passing behind the Whirlpool. The small galaxy has been gliding past the Whirlpool for hundreds of millions of years. The Whirlpool is one of astronomy's galactic darlings. Located 31 million light-years away in the constellation Canes Venatici (the Hunting Dogs), the Whirlpool's beautiful face-on view and closeness to Earth allow astronomers to study a classic spiral galaxy's structure and star-forming processes.