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NASA's Hubble Space Telescope photographed three magnificent sections of the
Veil Nebula — the shattered remains of a supernova that exploded thousands of
years ago. This series of images provides beautifully detailed views of the
delicate, wispy structure resulting from this cosmic explosion. The Veil Nebula
is one of the most spectacular supernova remnants in the sky. The entire shell
spans about 3 degrees on the sky, corresponding to about 6 full moons. The
Veil Nebula is a prototypical middle-aged supernova remnant, and is an ideal
laboratory for studying the physics of supernova remnants because of its
unobscured location in our Galaxy, its relative closeness, and its large size.
Also known as the Cygnus Loop, the Veil Nebula is located in the constellation
of Cygnus, the Swan. It is about 1,500 light-years away from Earth.
Stars in our Galaxy, and in other galaxies, are born and then die. How long a
star lives depends on how massive it is. The more massive the star, the shorter
its life. When a star significantly more massive than our Sun runs out of fuel,
it collapses and blows itself apart in a catastrophic supernova explosion. A
supernova releases so much light that it can outshine a whole galaxy of stars
put together. The exploding star sweeps out a huge bubble in its surroundings,
fringed with actual stellar debris along with material swept up by the blast
wave. This glowing, brightly colored shell of gas forms a nebula that
astronomers call a "supernova remnant."
Such a remnant can remain visible long after the initial explosion fades
away. Scientists estimate that the Veil supernova explosion occurred some 5,000
to 10,000 years ago.
The small regions captured in these Hubble images provide stunning close-ups
of the Veil. Fascinating smoke-like wisps of gas are all that remain visible of
what was once a star in our Milky Way Galaxy. The intertwined rope-like
filaments of gas in the Veil Nebula result from the enormous amounts of energy
released as the fast-moving debris from the explosion plows into its
surroundings and creates shock fronts. These shocks, driven by debris moving at
600,000 kilometers per hour, heat the gas to millions of degrees. It is the
subsequent cooling of this material that produces the brilliant glowing colors.
The Hubble images of the Veil Nebula are striking examples of how processes
that take place hundreds of light-years away can sometimes resemble effects we
see around us in our daily life. Although caused by different forces, the
structures show similarities to the patterns formed by the interplay of light
and shadow on the bottom of a swimming pool, rising smoke, or a ragged cirrus
cloud.
Although only about one star per century in our Galaxy will end its life in
this spectacular way, these explosions are responsible for making all chemical
elements heavier than iron, as well as being the main producers of oxygen in the
universe. Elements such as copper, mercury, gold, and lead are forged in these
violent events. The expanding shells of supernova remnants mix with other clouds
in the Milky Way and become the raw material for new generations of stars and
planets. The chemical elements that constitute Earth, and indeed those of which
we ourselves are made, were formed deep inside ancient stars and distributed by
supernova explosions in nebulae like the one we see here.
The images were taken with Hubble's Wide Field Planetary Camera 2 (WFPC2) in
November 1994 and August 1997. The color is produced by creating a composite of
three different images. The colors indicate emission from different kinds of
atoms excited by the shock: blue shows oxygen, green shows sulfur, and red shows
hydrogen.
For additional information, contact:
Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu
Keith Noll
Space Telescope Science Institute, Baltimore, Md.
410-338-1828
noll@stsci.edu
Lars Lindberg Christensen
Hubble/ESA, Garching, Germany
011-49-89-3200-6306
lars@eso.org
Object Name: Veil
Nebula
Image Type:
Astronomical
Credit:
NASA,
ESA, and the
Hubble Heritage (STScI/AURA)-ESA/Hubble
Collaboration
Acknowledgment:
J. Hester (Arizona State University) |
