Credit: Processing -
Noel
Carboni,
Imaging - Greg Parker,
New Forest
Observatory
Explanation:
Is this coat hanger a star cluster or an asterism?
This
cosmic hang-up has been debated over much of last century,
as astronomers wondered whether this binocular-visible object is
really a physically associated
open cluster or a chance projection.
Chance star projections are known as
asterisms, an example of which is the popular
Big Dipper.
Recent precise measurements from different vantage points in the Earth's orbit around the Sun
have uncovered discrepant angular shifts indicating that the
Coat Hanger
is better described as an
asterism.
Known more formally as
Collinder 399,
this bright stellar grouping is wider than the
full moon and lies in the
constellation of the
Fox
(Vulpecula).
On the far right of the image is the
open cluster of stars
NGC 6802.
Note : APOD Editor to Speak in New York on Jan. 2
January February March April May June July August September October November December |
|
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: asterism - open cluster
Publications with words: asterism - open cluster
See also: