The Champagne Flows
There's a hot party going on in M17. Buried inside this nebula of glowing material,
gas flows outward "like champagne flows out of a bottle when the cork is removed,"
astronomers said yesterday, so it has been termed an "X-ray champagne flow."
The flow occurs becase the gas is hot -- up to 13 million degrees Fahrenheit
(7 million degrees Celsius).
It's not clear what heats the gas. In some nebulae, exploding stars provide
the energy. But the stars in M17 are only about a million years old -- too young
to have exploded. Astronomers think high-speed winds of charged particles, streaming
away from the massive stars, might heat the gas. Or, they say, maybe the heat
is created when the winds slam into cooler surrounding clouds.
This new image from NASA's Chandra X-ray Observatory, released yesterday, helped
scientists pin down the uncorked flow and show that the sources of "carbonation"
are the massive young stars seen in the bright pink area near the center.
M17 hardly needs the bubbly descriptor. It already
goes by several names -- the Swan, Omega, Checkmark or Lobster Nebula. It's
also called the Horseshoe Nebula, for reasons not apparent in this image. The
gas seen with Chandra's X-ray vision is housed inside a larger horseshoe-shaped
gas cloud that had been previously
imaged in infrared wavelengths.
Earlier this year, astronomers released a beautiful
Hubble Space Telescope image showing a close-up
of one part of M17.
-- Robert
Roy Britt
Credit: NASA/CXC/PSU/L.Townsley
et al.
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