APOD: Cats Eye Nebula August 4, 2008Posted by Sarah in science.
Tags: astronomy, nasa
The Astronomy Picture of the Day is really awsome today. It’s a composite image of the Cat’s Eye Nebula (NGC6543), combining optical images from the Hubble Space Telescope with X-rays detected with the X-ray mission Chandra.
The well-known Hubble composite image is already very beautiful but the addition of the X-ray data makes it really stunning.
NGC6543 is a great example of a planetary nebula: the central star is in its final death throes, becomes gravitationally unstable as it runs out of fuel to sustain the nuclear fusion reactions that have powered it throughout its lifetime. The star has ejected its gassy envelope, which is receding from it at 4 million miles an hour. The beautiful filamentary structure seen in the image is caused by powerful blast waves colliding with other material in the star’s surroundings. The scorching hot core left at the centre will continue collapsing further to become a white dwarf.