The Sun Rips Off a Comet's Tail (NASA Feature)
Encke never knew what hit it. On April 20, 2007, the comet had
just dipped inside the orbit of Mercury, perilously close to the
sun, when a solar eruption struck and literally tore the comet's
tail off. This surely has happened to comets before, but for the
first time in history a spacecraft was watching. NASA's STEREO-A
probe recorded a fantastic movie of the collision.