APOD: 2023 January 29 Б Barnard 68: Dark Molecular Cloud
Explanation:
Where did all the stars go?
What used to be considered a hole in the sky
is now known to astronomers as a dark molecular cloud.
Here, a high concentration of
dust and
molecular gas
absorb practically all the
visible light
emitted from background stars.
The eerily dark surroundings help make the interiors of
molecular clouds some of the coldest
and most
isolated
places in the universe.
One of the most notable of these
dark absorption nebulae
is a cloud toward the constellation
Ophiuchus known as
Barnard 68,
pictured here.
That no stars are visible in the center indicates that
Barnard
68 is relatively nearby, with measurements placing it about
500 light-years away and half a
light-year across.
It is
not known exactly how
molecular clouds like
Barnard 68 form,
but it is known that these clouds are themselves
likely
places
for new stars to form.
In fact, Barnard 68 itself has
been found likely to collapse and form a new star system.
It is possible to
look right through the cloud in
infrared light.
Postcards from the Universe 2022:
APOD Year in Review
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.
