2007-03-14 | SCIENCE
NASA's Cassini Spacecraft Images Seas on Titan

Photogenic Saturn has now become a movie star. Astronomers have woven NASA Hubble Space Telescope images of Saturn, its rings, and several of its moons into three movies. Each movie highlights unique times in the planet's 30-year waltz around the Sun. Two of the movies show the motion of several of Saturn's moons when the planet's rings were tilted nearly edge-on to Earth and to the Sun. These edge-on alignments of the rings occur roughly once every 15 years. Another movie presents a clear view of Saturn's Southern Hemisphere when the planet's rings were at maximum tilt toward Earth. Hubble snapped only about a dozen images during each of these three events, so astronomers created software to extend the photos into the hundreds of images needed for a movie. The images were taken with Hubble's Wide Field and Planetary Camera 2 in 1995 and the Advanced Camera for Surveys in 2003.

In March 2003, Saturns rings were at maximum tilt toward Earth, a special event occurring every 15 years. With the rings fully tilted, astronomers get the best views of the planets Southern Hemisphere. They took advantage of the rings' unique alignment by using Hubble to capture some stunning images.

Astronomers then wove those images into a time-lapse movie of Saturns rotation and southern region. The planet spins more than twice as fast as Earth does, completing a rotation every 10 hours. As Saturn rotates, so do its rings. But the ring material is so evenly spread out along each ring that in this movie one cannot see the rings rotating around Saturn.

After showing Saturn spinning, the movie then offers a close-up of the planets Southern Hemisphere. Astronomers enhanced the contrast in this close-up sequence to make Saturns features more apparent. The close-up views reveal the planets banded cloud structure, which is similar to Jupiters. Saturns clouds, however, are beneath a thick layer of haze. The haze, however, does not obscure several storms  the blue and white spots  in the planets dynamic atmosphere.

The preceding news links are provided as a public service for interested users. The views and claims expressed in external internet sites are not necessarily those of NASA.