A jet of gas firing out of a very young star can be seen ramming into a
wall of material in this infrared image from NASA's Spitzer Space
Telescope.
The young star, called HH 211-mm, is cloaked in dust and can't be seen.
But streaming away from the star are bipolar jets, color-coded blue in
this view. The pink blob at the end of the jet to the lower left shows
where the jet is hitting a wall of material. The jet is hitting the wall
so hard that shock waves are being generated, which causes ice to vaporize
off dust grains. The shock waves are also heating material up, producing
energetic ultraviolet radiation. The ultraviolet radiation then breaks the
water vapor molecules apart.
The red color at the end of the lower jet represents shock-heated iron,
sulfur and dust, while the blue color in both jets denotes shock-heated
hydrogen molecules.
HH 211-mm is part of a cluster of about 300 stars, called IC 348, located
1,000 light-years away in the constellation Perseus.
This image is a composite of infrared data from Spitzer's infrared array
camera and its multiband imaging photometer. Light with wavelengths of 3.6
and 4.5 microns is blue; 8-micron-light is green; and 24-micron light is
red.