APOD: 2007 February 23- Dust and the Helix Nebula
Explanation:
Dust makes this cosmic eye look red.
The eerie
Spitzer Space Telescope image
shows
infrared
radiation from the well-studied
Helix Nebula (NGC 7293) a mere
700 light-years away in the constellation
Aquarius.
The two light-year diameter shroud of dust and gas around
a central white dwarf has long been considered an excellent
example of a
planetary
nebula, representing the final stages
in the evolution of a sun-like star.
But the Spitzer data show the nebula's central star itself
is immersed in a surprisingly bright infrared glow.
Models
suggest the glow is produced by a dust
debris
disk.
Even though the nebular material was ejected from the star
many thousands of years ago,
the close-in dust could be generated by collisions in
a reservoir of objects analogous to our own solar system's
Kuiper
Belt or cometary
Oort cloud.
Formed in the distant planetary system, the comet-like bodies have
otherwise survived even the dramatic late stages of the star's
evolution.
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.
