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Астронет: Астрономическая картинка дня IC 4603: отражательная туманность в Змееносце http://variable-stars.ru/db/msg/1222317/eng |
Credit & Copyright: Takayuki Yoshida
Explanation:
Why does this starfield photograph resemble an
impressionistic painting?
The effect is created not by
digital trickery but by large amounts of
interstellar dust.
Dust, minute globs rich in
carbon and similar in
size to
cigarette smoke, frequently starts in the
outer atmospheres of large, cool, young stars.
The dust is dispersed as the star dies and grows as things stick to it in the
interstellar medium.
Dense dust clouds are
opaque to
visible light and can completely hide background stars.
For less dense clouds, the capacity of dust to
preferentially reflect blue starlight becomes important,
effectively blooming the stars blue light out and marking the surrounding dust.
Nebular gas emissions, typically brightest in
red light,
can combine to form areas seemingly created on an artist's canvas.
Photographed above
is roughly four square degrees of the nebula
IC 4603 near the bright star
Antares toward the
constellation of
Ophiuchus.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.