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- The Eagle Nebula (M16)
in Serpens gained fame
in the 1990s, when the
Hubble Space Telescope
photographed three
“Pillars of Creation.” In this
Spitzer infrared view, the
pillars appear as greenish
columns protruding in
front of some reddish
nebulosity to the right
of center. The green
denotes cool dust, while
red signifies warmer
material that might have
been energized by a
supernova explosion 1,000
to 2,000 years ago. NASA/
JPL-CALTECH/N. FLAGEY (IAS/SSC)/
A. NORIEGA-CRESPO (SSC/CALTECH) - The universe has a
different look at infrared
wavelengths. In visible
light, dark dust blocks the
glow of more distant gas
to create the outline of the
North America Nebula
(NGC 7000) in Cygnus.
But the continent
disappeared to Spitzer’s
eye because it peered
through this dust to reveal
the cocoons of embryonic
stars within the nebula.
Many of the stars seen
here are only about a
million years old. NASA/JPL-
CALTECH/L. REBULL (SSC/CALTECH)
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- The Carina Nebula
(NGC 3372) hosts one
of the most massive
and luminous stars
in our galaxy, Eta
Carinae, which
gleams at the center
of this Spitzer image.
Infrared light from this
behemoth destroys
dust particles and
sculpts cavities into
the surrounding
nebula. The dust
glows red in this
image and hydrogen
gas appears green.
NASA/JPL-CALTECH - Spitzer proved to
be a revelation for
astronomers studying
star formation. The
Lagoon Nebula (M8)
in Sagittarius offers
a vivid example. In
visible light, the glow
from ionized hydrogen
veils the Lagoon’s
inner workings. But at
infrared wavelengths,
the gas disappears
and we see myriad
young stars as well as
warm carbon-based
dust grains (green)
and hot dust particles
(red). NASA/JPL-CALTECH