Hidden behind a shroud of dust in the constellation Cygnus is a
stellar nursery called DR21, which is giving birth to some of the most
massive stars in our galaxy. Visible light images reveal no trace of this
interstellar cauldron because of heavy dust obscuration. In fact, visible
light is attenuated in DR21 by a factor of more than
10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand
trillion heptillion).
New images from NASA's Spitzer Space Telescope allow us to peek behind
the cosmic veil and pinpoint one of the most massive natal stars yet seen
in our Milky Way galaxy. The never-before-seen star is 100,000 times as
bright as the Sun. Also revealed for the first time is a powerful outflow
of hot gas emanating from this star and bursting through a giant molecular
cloud.
The colorful image is a large-scale composite mosaic assembled from
data collected at a variety of different wavelengths. Views at visible
wavelengths appear blue, near-infrared light is depicted as green, and
mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's
Spitzer Space Telescope is portrayed as red. The result is a contrast
between structures seen in visible light (blue) and those observed in
the infrared (yellow and red). A quick glance shows that most of the
action in this image is revealed to the unique eyes of Spitzer. The
image covers an area about two times that of a full moon.