Friday, July 24, 2009
A Giant Soap Bubble Floating in Space ?
It looks like a soap bubble or perhaps even a camera fault, but the image is a newly discovered planetary nebula.
Planetary nebulae, which got their name after being misidentified by early astronomers, are formed when an aging star weighing up to eight times the mass of the sun ejects its outer layers as clouds of luminous gas.
Most are elliptical, double-lobed or cigar-shaped, evolving after stars eject gas from each pole.
The bubble, which was officially named PN G75.5+1.7 last week, has been there a while. A closer look at images from the second Palomar Sky Survey revealed it had the same size and brightness 16 years ago but was overlooked because it is very faint.
The "Cygnus Bubble" nebula may actually be a cylinder that is being seen from one of its ends, looking down the throat of a typical cylindrical nebula.. This image was taken with the Kitt Peak Mayall 4-metre telescope in Arizona.
Posted by Bob at 7:53 AM