Copyright: ESA, NASA, HEIC and The Hubble Heritage Team (STScI/AURA)
Three thousand light years from Earth, the Cat’s Eye Nebula (NGC
6543) is a sight that draws in the human eye. In this image from the
NASA/ESA Hubble Space Telescope, numerous bubbles are visible – shapes
generated by the ejection of glowing gas as the star at its centre
approaches the end of its life.
While large stars die in supernova
explosions, average Sun-like stars form planetary nebulas as they
exhaust their fuel supplies and slowly expire. The name ‘planetary
nebula’ arose because the round shape, sculpted as layers of material
are ejected, looked a little like a planet in small telescopes.
The
Cat’s Eye Nebula was discovered by William Herschel in 1786, and
remains an interesting target for ground-based astronomers. Amateurs can
see the magnitude 8.1 blob in the sky well enough to resolve the Cat’s
Eye shape, while large telescopes have identified a wider halo extending
into space.
This image was published on the ESA Portal in 2004,
but the Hubble Space Telescope first revealed the nebula’s intricate
structure in 1994.
Observations of its intricate concentric gas
shells and unusual shock-induced knots of gas suggest that the star
ejected its mass in a series of pulses at 1500 year intervals. These
convulsions created dust shells that each contain as much mass as all of
the planets in our Solar System combined.
Source: ESA - Space Images
