A snow line in an infant solar system: Astronomers take first images.

This is from the University of Michigan News Service:

Published on Jul 18, 2013

ANN ARBOR—Like the elevation in the Rocky Mountains where the snow caps begin, a snow line in a solar system is the point where falling temperatures freeze and clump together water or other chemical compounds that would otherwise be vapor. Astronomers believe snow lines in space serve a vital role in forming planets because frozen moisture can help dust grains stick together. 

Astronomers have, for the first time, directly imaged a snow line at another star.

For the full article see...

http://www.ns.umich.edu/new/releases/21595-a-snow-line-in-an-infant-solar-system-astronomers-take-first-images