Slice of Shadow
This 2012 photo from NASA’s Cassini probe showcases the B ring, which is so opaque that it casts a pitch-black shadow onto Saturn. It also hints at the rings’ size: The moon Tethys, upper left, is 660 miles (1,062 kilometers) wide.
Saturn’s Ring Puffs Itself Up With Optical Illusion
Saturn’s rings still hold mysteries—including a trick that makes one of its biggest rings look even bigger.
With a magic trick that’s more smoke than mirrors, one of Saturn’s most mysterious rings has deceived astronomers for decades with an optical illusion.
As described by astronomers Matt Hedman and Phillip Nicholson, the B ring—Saturn’s brightest—has been deceptively opaque, making astronomers think that it contains up to seven times more mass than it actually does.
The study, published January 22 in the journal Icarus, marks the latest attempt to weigh the B ring, an important piece of data for understanding how Saturn’s rings formed.
The planet’s other rings haven’t proven nearly so tricky. Astronomers used density waves, ripples that form like a traffic jam as ring particles get jostled by Saturn’s moons. Change a ring’s density, and the
