Astronomy Picture of the Day 04-30-04

Explanation: Now a bright speck of light wandering through Earth's night sky, magnificent planet Saturn lies nearly 1.5 billion kilometers from the Sun. But after an interplanetary voyage of seven years the planet's stunning rings nearly fill the field of the Cassini spacecraft's narrow angle camera in this image recorded on March 27. Tip to tip, the ring system spans about 270,000 kilometers. Named for discoverers, the large, easily visible gap in the rings is known as the Cassini division, while the narrower outer gap is the Encke division. Illuminated from below and to the right, the rings cast a shadow on Saturn's upper hemisphere, interrupted where sunlight streams through the Cassini division and creates a light blue streak. At the left, Saturn also casts a stark shadow across the planet girdling rings. On July 1, the Cassini spacecraft is scheduled to fire its main engine and enter Saturn orbit.

Cassini snaps its final full view of Saturn and rings
NASA NEWS RELEASE
Posted: April 29, 2004

Saturn and its rings completely fill the field of view of Cassini's narrow angle camera in this natural color image taken on March 27, 2004. This is the last single "eyeful" of Saturn and its rings achievable with the narrow angle camera on approach to the planet. From now until orbit insertion, Saturn and its rings will be larger than the field of view of the narrow angle camera.

Credit: NASA/JPL/Space Science Institute
Download a larger version here

Color variations between atmospheric bands and features in the southern hemisphere of Saturn, as well as subtle color differences across the planet's middle B ring, are now more distinct than ever. Color variations generally imply different compositions. The nature and causes of any compositional differences in both the atmosphere and the rings are major questions to be investigated by Cassini scientists as the mission progresses.

The bright blue sliver of light in the northern hemisphere is sunlight passing through the Cassini Division in Saturn's rings and being scattered by the cloud-free upper atmosphere.

Two faint dark spots are visible in the southern hemisphere. These spots are close to the latitude where Cassini saw two storms merging in mid-March. The fate of the storms visible here is unclear. They are getting close and will eventually merge or squeeze past each other. Further analysis of such dynamic systems in Saturn's atmosphere will help scientists understand their origins and complex interactions.

Moons visible in this image are (clockwise from top right): Enceladus (499 kilometers or 310 miles across), Mimas (398 kilometers or 247 miles across), Tethys (1060 kilometers or 659 miles across) and Epimetheus (116 kilometers or 72 miles across). Epimetheus is dim and appears just above the left edge of the rings. Brightnesses have been exaggerated to aid visibility.

The image is a composite of three exposures, in red, green and blue, taken when the spacecraft was 47.7 million kilometers (29.7 million miles) from the planet. The image scale is 286 kilometers (178 miles) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter and its two onboard cameras, were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.

Soyuz brings station crew back to Earth
BY WILLIAM HARWOOD
STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted: April 29, 2004

Outgoing space station commander Michael Foale, flight engineer Alexander Kaleri and Dutch astronaut Andre Kuipers returned to Earth aboard a Soyuz ferry craft this evening, safely touching down on target in Kazakhstan at 8:12 p.m. EDT (0012 GMT).

Recovery crews had the spacecraft in sight during the latter stages of its descent and helicopters carrying flight surgeons and other personnel were on the scene in minutes. Within 15 minutes of landing, all three crew members had been assisted out of the cramped, upright Soyuz and helped into reclining chairs. Support crews offered hot tea and congratulations.

"A bullseye touchdown for the crew," reported NASA spokesman Rob Navias, on the scene in north central Kazakhstan. "It's a brilliant morning, the sun is just beginning to rise, crystal clear skies, just perfect weather, no wind at all.

"Again, Andre Kuipers in the process of being extracted, Mike Foale flashing me a smile, I'm standing right in front of him at the moment. Alexander Kaleri is in the process of talking to former cosmonaut Alexander Alexandrov from RSC Energia as he takes a sip of tea, having guided the Soyuz TMA-3 capsule to an on-target, bullseye touchdown. ... A very jubilant scene here in north central Kazakhstan."

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.