New kind of ring around Saturn.

It is believed that barring extraordinary circumstances the Saturn satellite Titan must lose its atmosphere at a prodigious rate. The velocity of the atmospheric particles, however, although sufficient to escape from the satellite, does not quite reach Saturnian escape velocity. Consequently, atoms and molecules lost by Titan are forced by the planet's gravitational field to orbit Saturn until ionized or until they are recaptured by Titan, forming a gaseous torus encompassing Titan's orbit.