<a href="//commons.wikimedia.org/wiki/Category:Cassini-Huygens" title="Category:Cassini-Huygens">Cassini</a> has been snapping visible-light photographs of <a href="//commons.wikimedia.org/wiki/Category:Saturn_(Rings)" title="Category:Saturn (Rings)">Saturn's rings</a>, the <a href="//commons.wikimedia.org/wiki/Composite" title="Composite">Composite</a> <a href="//commons.wikimedia.org/wiki/Category:Infrared" title="Category:Infrared">Infra-red</a> Spectrometer instrument was taking the rings' temperatures. During <a href="//commons.wikimedia.org/wiki/Category:Equinox" title="Category:Equinox">equinox</a>, the rings cooled to the lowest temperature ever recorded. The A ring dropped down to a frosty 43 <a href="https://en.wikipedia.org/wiki/Kelvin" class="extiw" title="en:Kelvin">Kelvin</a>. Studying ring temperatures at equinox will help scientists better understand the sizes and other characteristics of the ring particles.
NASA/JPL/Space Science Institute
<a rel="nofollow" class="external text" href="http://www.jpl.nasa.gov/news/news.cfm?release=2009-142">NASA JPL</a>