Wednesday, February 25, 2009
Astronomers photograph Eye of God
This is very cool.
My friend Giles of the Blue Gallery in London, which exhibits these images has provided me with the following copy to accompany this image:
The Helix Nebula (NGC7293)
source: HST - Advanced Camera for Surveys. November 19th 2002.
Kitt Peak Observatory, Arizona. November 3rd 2001.
distance from Earth: 450 light years.
location: In the constellation Aquarius in the Milky Way galaxy.
image width: 5.1 light years.
This photograph of the coil-shaped Helix Nebula is one of the largest
and most detailed celestial images ever made and its detail is simply
magnificent. The composite picture is a seamless blend of ultra-sharp
images from the Hubble Space Telescope with a wider view taken by the
0.9-meter telescope at Kitt Peak National Observatory, near Tucson in
The Helix Nebula is the closest planetary nebula to Earth and hence
one of the most consistently observed. A planetary nebula is the
region of ejected, irradiated gases surrounding a dying star. What
appears to be an ellipse surrounding the star is in fact more of a
trillion mile long cylinder-shaped structure seen almost head on. It
is estimated that the process of ejection of these gases began some
10,000 years ago, as a star of comparable mass to the Sun exhausted
its possible sources of fuel for thermonuclear fusion. It subsequently
collapsed under its own gravity, compressing its constituent matter to
a degenerate state, in which atomic nuclei and electrons that have
been completely stripped from atoms are all packed together. Mass
remains but now its size and luminosity are hugely reduced and the
star has become a "white dwarf", unable to generate new energy. It is
destined in due course to gradually cool and fade into a black dwarf,
an utterly dormant body of stellar material, of which it is assumed
there are none as yet, as the universe is not of sufficient age. It
has been deduced that the upper mass limit for white dwarves is 1.4
solar masses. Any larger and the consequence of the process is a
neutron star - or if greater than 3 solar masses, a black hole.
The image shows a fine web of filamentary "bicycle-spoke" features
embedded in the colorful red and blue ring of gas. The radial fingers
of gas are caused by the immense ultraviolet radiation that the white
dwarf (central star) emits. [See also the text for The Helix Nebula
(NGC7293) - a detail] Image courtesy NASA, ESA, AURA/STScI and NOAO.
120 x 120 cm Durst Lambda print on Fujicolour Crystal archive paper
dry mounted onto 3 mm dibond