Planet that never was is still interesting

Astronomers believe it was caused by a cosmic collision.

star formation_planet
The colour-tinted image on the left shows a vast ring of icy debris encircling the star Fomalhaut. The diagram on the right is based on simulation of an expanding and fading cloud of very fine dust particles. Credit: NASA, ESA, A. Gáspár and G. Rieke/University of Arizona