Friday, August 15, 2008

Cassini Pinpoints Source Of Jets On Saturn's Moon Enceladus

It's no secret that I am a big Cassini fan. Every picture from this craft extends our knowledge base of the Saturn. Truth be told though, the vast majority of people disregard the shear distance and technological wizardry that is involved with controlling and receiving pictures from the craft. As a photographer, I am wowed by many of the photos, but these last few of Enceladus and the effort involved in taking high resolution frames. Most of Cassini's pictures are taken with a wide field of view where a little motion relative to the craft are easily compensated for. It's this latest pass that really had me saying "you have got to be kidding me!" Because Cassini was moving so fast and so close to the moon's surface, the effect was, in the words of controller Paul Helfenstein "skeet shooting". He describes it this way.
  • "The challenge is equivalent to trying to capture a sharp, unsmeared picture of a distant roadside billboard with a telephoto lens out the window of a speeding car."
  • Helfenstein said that from Cassini's point of view, "Enceladus was streaking across the sky so quickly that the spacecraft had no hope of tracking any feature on its surface. Our best option was to point the spacecraft far ahead of Enceladus, spin the spacecraft and camera as fast as possible in the direction of Enceladus' predicted path, and let Enceladus overtake us at a time when we could match its motion across the sky, snapping images along the way."
Amazing.... and even more exciting is the fact that they managed to catch the areas they were looking for which was the geysers that had been documented earlier. The article is a wealth of information.
<- check it out here ->

No comments: