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Cassini Continues Making New Saturn Discoveries

Thursday, February 24, 2005

The Greatest Saturn Portrait ...Yet

NASA/JPL/Space Science Inst.

NASA's Cassini spacecraft continues making new and exciting discoveries. New findings include wandering and rubble-pile moons; new and clumpy Saturn rings; splintering storms and a dynamic magnetosphere. Weak, linear density waves caused in Saturn's rings by the small moons Atlas and Pan have yielded more reliable calculations of their masses. The masses imply the moons are very porous, perhaps constructed like rubble piles. They are similar to the moons that shepherd Saturn's F ring, Prometheus and Pandora. Another discovery was a tiny moon, about 5 kilometers (3 miles) across, recently named Polydeuces. Polydeuces is a companion, or "Trojan" moon of Dione. Trojan moons are found near gravitationally stable points ahead or behind a larger moon. Saturn is the only planet known to have moons with companion Trojan moons.

More: JPL - NASA's Cassini Spacecraft Continues Making New Saturn Discoveries

Link: USGS - Cassini Mission

Features on Saturn's Moon Phoebe Get Names

Thursday, February 24, 2005

Phobeian Explorers
Phoebian Explorers 1


The International Astronomical Union (IAU) has provisionally assigned names to craters on Saturn's moon Phoebe. These newly identified craters are named for the Argonauts, explorers of Greek mythology who sought the golden fleece. Argo was the name of their ship. Like many of the other moons of Saturn, Phoebe takes its name from the Titans of Greek mythology.

USGS Astrogeology maintains the official list of planetary feature names for the IAU, called the Gazetteer of Planetary Nomenclature. Additionally, we are active on several IAU working and task groups.

More: USGS Astro - Phoebe's Craters on the Official Gazeteer of Planetary Nomenclature view the complete list of craters and the origin of each name

Image: NASA/JPL - Phoebian Explorers 1 (PIA06117)

Image: NASA/JPL - Phoebian Explorers 2 (PIA06118)

Link: Wikipedia - Jason and the Argonauts

Spirit and Opportunity Continue Explorations

Tuesday, February 15, 2005

rover concept art
Mars Rover artwork

After more than a year on Mars, rovers Spirit and Opportunity are still actively exploring. Spirit's solar panels are collecting a fine layer of dust, which has reduced energy levels. Despite the dust, Spirit has recently visited "Cumberland Ridge" and has been moving towards "Larry's Lookout." Opportunity is in good health, and has completed its investigation of a trench and soil materials under clear skies. Both rovers are scheduled for software updates.

More: JPL - Spirit Status Report

More: JPL - Opportunity Status Report

Link: USGS Astro - Mars Exploration Rover Project

ESA's Lunar SMART-1 Mission Extended

Tuesday, February 15, 2005

SMART-1 artwork
SMART-1 artist's impression


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The European Space Agency's SMART-1 mission, in orbit around the Earth's Moon, was extended by one year, pushing back the mission end date from August 2005 to August 2006. The extension by one year of the mission will provide opportunities to extend the global coverage, compared to the original six-month mission, and to map both southern and northern hemispheres at high resolution. The new orbit will also be more stable and require less fuel for maintenance. The extension also gives the possibility to perform detailed studies of areas of interest by performing stereo measurements for deriving topography, multi-angle observations for studying the surface 'regolith' texture, and mapping potential landing sites for future missions.

More: ESA - SMART-1 Mission Extended