Cat's
Eye
Explanation:
Staring across interstellar space, the alluring
Cat's Eye nebula lies three thousand light-years
from Earth. A classic planetary nebula, the
Cat's Eye (NGC 6543) represents a final, brief
yet glorious phase in the life of a sun-like
star. This nebula's dying central star may have
produced the simple, outer pattern of dusty
concentric shells by shrugging off outer layers
in a series of regular convulsions. But the
formation of the beautiful, more complex inner
structures is not well understood. Seen so clearly
in this sharp Hubble Space Telescope image,
the truly cosmic eye is over half a light-year
across. Of course, gazing into the Cat's Eye,
astronomers may well be seeing the fate of our
sun, destined to enter its own planetary nebula
phase of evolution ... in about 5 billion years.
[Astronomy
Picture of the Day: [24.09.05] Cat's Eye]
The Eye of God
Explanation:
Will our Sun look like this one day? The Helix
Nebula is the closest example of a planetary
nebula created at the end of the life of a Sun-like
star. The outer gasses of the star expelled
into space appear from our vantage point as
if we are looking down a helix. The remnant
central stellar core, destined to become a white
dwarf star, glows in light so energetic it causes
the previously expelled gas to fluoresce. The
Helix Nebula, given a technical designation
of NGC 7293, lies about 650 light-years away
towards the constellation of Aquarius and spans
about 2.5 light-years. The above picture is
a composite of newly released images from the
ACS instrument on the Hubble Space Telescope
and wide-angle images from the Mosaic Camera
on the WIYN 0.9-m Telescope at Kitt Peak National
Observatory. A close-up of the inner edge of
the Helix Nebula shows complex gas knots of
unknown origin.
[Astronomy
Picture of the Day: [10.05.03] NGC7293: The
Helix Nebula]
Smelltu
hér til að skoða fleiri myndir
á Astronomy Picture of the Day
Keyptu
þér land á tunglinu
Var
Apollo-ferðin 1969 til tunglsins bara blekking?
Taktu
þátt í leitinni að geimverum[SETI@home]
Nú
langar mig að vita, trúið þið
á líf á öðrum
plánetum? Ertu Mulder eða ertu Scully?
:)
