A University of Idaho assistant professor is among the team analyzing a striking new image of Saturn released Tuesday by NASA.
The composite uses 141 photos taken on July 19 of this year, when the Cassini probe was able to photograph Saturn backlit by the sun. The image's main purpose is as a tool to examine changes in Saturn's rings over time. But the probe was also able to catch a glimmer of Earth in the background - something NASA's Jet Propulsion Laboratory knew and promoted ahead of time, encouraging people to "Wave at Saturn" on the date of the photos.
This image shows the Saturn system from a completely different perspective than we could ever get from Earth. Basically, it is an eclipse of the sun by Saturn, so we are seeing light filtered through the planet's atmosphere and the rings, Matt Hedman, a U of I assistant professor of physics, said in a Tuesday press release.
U of I researchers have long been involved with Cassini, which reached Saturn in 2004 and has been used to study the ringed gas giant since. David Atkinson, an electrical and computer engineering professor, chaired a working group focused on the descent trajectory of the Huygens probe, which split off from Cassini and landed on Saturn's moon Titan in 2005.
Associate physics professor Jason Barnes and four students are also currently involved with Cassini, focusing on other research regarding Titan.
According to NASA, Tuesday's new image shows an area 404,880 miles across, covering Saturn and its inner rings. Earth is visible as a blue dot just to the lower right of Saturn. Mars and Venus are visible on the other side of the image.
Cassini does not attempt many images of Earth, according to NASA, because of the sun's proximity; an unobstructed view would damage the spacecraft's sensitive detectors.