Silicate Crystal Formation in the Disk of an Erupting Star This
artist's animation illustrates how silicate crystals like those
found in comets can be created by an outburst from a growing
star. It first shows a young sun-like star encircled by its
planet-forming disk of gas and dust. The silicate that makes up
most of the dust would have begun as non-crystallized, amorphous
particles. Then, material from the disk spirals onto the star
increasing its mass and causing the star to brighten and heat up
dramatically. The outburst causes temperatures to rise in the
star's surrounding disk. Next, the animation zooms into the disk
to show close-ups of silicate particles. When the disk warms
from the star's outburst, the amorphous particles of silicate
melt. As they cool off, they transform into forsterite, a type
of silicate crystal often found in comets in our solar system.
In April 2008, NASA's Spitzer Space Telescope detected evidence
of this process taking place on the disk of a young sun-like
star called EX Lup