W5: Pillars of Star Formation
Explanation:
How do stars form?
Images of the star forming region
W5
like those in the
infrared by NASA's Wide Field Infrared Survey Explorer (WISE) satellite
provide clear clues with indications that massive stars near the center of empty
cavities are older than stars near the edges.
A likely reason for this is that the older stars in the center are actually
triggering
the formation of the younger edge stars.
The triggered
star formation
occurs when hot outflowing gas compresses cooler gas into
knots dense
enough to gravitationally contract into stars.
In the
featured
scientifically-colored infrared image,
spectacular pillars,
left slowly evaporating from the hot outflowing gas,
provide further
visual clues.
W5 is also known as
IC 1848, and
together with IC 1805
form a complex region of star formation popularly dubbed the
Heart
and
Soul Nebulas.
The
above image
highlights a part of W5 spanning about 2,000
light years that is rich in
star forming pillars.
W5 lies about 6,500 light years away toward the
constellation of
Cassiopeia.
Now Available:
APOD 2015 Wall Calendars
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.
