Астронет: Астрономическая картинка дня Туманность Медуза http://variable-stars.ru/db/msg/1337448/eng |
Credit & Copyright: European Southern Observatory,
VLT
Explanation:
Braided, serpentine filaments of glowing gas
suggest this nebula's popular name, The Medusa Nebula.
Also known as Abell 21, this Medusa is an old
planetary nebula
some 1,500 light-years away along the southern border of the constellation
Gemini.
Like its mythological
namesake, the nebula is associated with a dramatic transformation.
The planetary
nebula phase represents a final stage in
the
evolution of low mass stars
like the
sun, as they transform themselves from
red giants
to hot white dwarf stars and in the process shrug off their outer layers.
Ultraviolet
radiation
from the hot star powers the nebular glow.
An unrelated, bright, foreground star is near center in this
close-up,
telescopic view,
while the Medusa's transforming central star is actually the dimmer
star below center and toward the right-hand part
of the frame.
The Medusa Nebula is estimated to be over 4 light-years across.
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.