Saturn’s Ice Queen, Helene Image Of A Moon

NASA’s Cassini spacecraft successfully completed its second-closest encounter with Saturn’s icy moon Helene on June 18, 2011, beaming down raw images of the small moon. At closest approach, Cassini flew within 4,330 miles (6,968 kilometers) of Helene’s surface. It was the second closest approach to Helene of the entire mission.

This I found on Tom’s Astronomy blog. Got to love the image. Saturn has so many moons it is hard to keep track of them all. What I like about this image is its clarity, the patterning on the moons surface and the light and shadow effects.

Hartley 2 A ‘Hyperactive’ Comet?

Images at the same scale for all cometary nuclei observed by spacecraft. Differences in overall shape are dramatic, as are the differences in contrast between the nuclei and their associated jets, which are brighter than the nucleus at Halley and Hartley 2 and much fainter than the nucleus at other comets. Credit: Science/AAAS
Images at the same scale for all cometary nuclei observed by spacecraft. Differences in overall shape are dramatic, as are the differences in contrast between the nuclei and their associated jets, which are brighter than the nucleus at Halley and Hartley 2 and much fainter than the nucleus at other comets. Credit: Science/AAAS

Centauri Dreams is reporting on a hyperactive comet. Comet off gasings occurs as comets move toward the sun. As the various volatiles are heated by the sun energy they move from a frozen state to a gaseous state. Sometimes the off gasings can be quite energetic. This article looks at the comet Hartley 2 an provide analysis of the results of the flyby which occurred last fall. The results come from a paper published in journal Science.