Hubble: X marks the spot of star formation glow
SPACE TELESCOPE SCIENCE INSTITUTE PHOTO RELEASE
Posted: January 4, 2001
The saying "X" marks the spot holds true in this NASA Hubble Space Telescope (HST) image where Hubble-X marks the location of a dramatic burst of star formation, very much like the Orion Nebula in our Milky Way galaxy, but on a vastly greater scale.
Giant gas clouds in NGC 6822 have held a special attraction for astronomers since their discovery by the visual observer E. E. Barnard in 1881. Edwin P. Hubble, after whom the HST is named, used the then-new 100-inch telescope at Mount Wilson Observatory in 1925 to make the first detailed photographic investigation of NGC 6822. The Hubble image reveals details too fine to be resolved from telescopes on the ground.
Stars form in groups from enormous clouds of gas and dust called giant molecular clouds. Once star formation begins in a molecular cloud, its rate accelerates until the process is stopped when one or more very massive hot stars are formed. At that point the clouds change from near darkness into the brightly glowing objects such as seen in Hubble-X. It is the intense ultraviolet radiation from the massive stars that causes the residual gas to glow. Radiation and gas outflows, called stellar winds, then cause the gas to disperse, bringing further star formation to an abrupt end.
The Hubble-X image was taken with Hubble's Wide Field Planetary Camera 2 (WFPC2) in September 1997, by astronomers C. Robert O'Dell of Vanderbilt University, Paul W. Hodge of the University of Washington, and R. C. Kennicutt, Jr. of Steward Observatory at the University of Arizona.
The image shows a nearly circular bright cloud at the core of Hubble-X. The cloud's diameter is about 110 light-years, and contains many thousands of newly formed stars in a central cluster. The brightest of these young stars are easily visible in the Hubble image, where they appear as numerous bright white dots.
Hubble-X is many times brighter and larger than the Orion Nebula, the brightest nearby star formation region in our own Milky Way galaxy. In fact, the tiny cloud just below Hubble-X, barely resolved even by HST, has about the same size and brightness as the Orion Nebula.
Stunning posters featuring images from the Hubble Space Telescope and world-renowned astrophotographer David Malin are now available from the Astronomy Now Store.
U.K. & WORLDWIDE STORE
Ride a rocket!
A 50-minute VHS video cassette from Spaceflight Now features spectacular "rocketcam" footage from April's launch of NASA's 2001 Mars Odyssey probe. Available from the Astronomy Now Store in NTSC format (North America and Japan) and PAL (UK, most of Europe, Australia and other countries).
The Infinite Journey
The triumphs and tragedies of the space program are recalled by those who were there in this glossy 240-page book from the Discovery Channel.
MORE - amazon.com
MORE - amazon.co.uk
Get e-mail updates
Sign up for our NewsAlert service and have the latest news in astronomy and space e-mailed direct to your desktop (privacy note: your e-mail address will not be used for any other purpose).
NEW! The NASA "Meatball" logo appears on a series of stylish baseball caps available now from the Astronomy Now Store.
U.K. & WORLDWIDE STORE
INDEX | PLUS | NEWS ARCHIVE | LAUNCH SCHEDULE
ASTRONOMY NOW | STORE
© 2013 Spaceflight Now Inc.