NGC 2359 - Le casque de Thor
Image Credit &
Copyright:
Martin Pugh
NGC 2359 is a helmet-shaped cosmic cloud with
wing-like appendages popularly called Thor's Helmet.
Heroically sized even for a
Norse god,
Thor's Helmet is about 30 light-years across.
In fact, the helmet is more like
an interstellar bubble, blown as a fast
wind from the bright, massive star near the bubble's center inflates
a region within the surrounding molecular cloud.
Known as a
Wolf-Rayet star,
the central star is an extremely hot giant thought to be in a brief,
pre-supernova stage of evolution.
NGC 2359 is located about
15,000 light-years away in the constellation of the
Great Overdog.
The remarkably sharp image
is a mixed cocktail of data from broadband and narrowband filters using
three different telescopes.
It captures natural looking stars and the details of
the nebula's
filamentary structures.
The predominant bluish hue is strong emission from doubly ionized
oxygen atoms
in the glowing gas.