Omega Centauri

Wise_wise2010-029_500

WISE_WISE2010-029 August 16th, 2010

Credit: NASA/JPL-Caltech/UCLA

NASAs Wide-field Infrared Survey Explorer, or WISE, has captured a favorite observing target of amateur astronomers -- Omega Centauri. Also known as NGC 5139, this celestial cluster of stars can be found in the constellation Centaurus and can be seen by the naked eye to observers at low northern latitudes and in the southern hemisphere. Omega Centauri contains approximately 10 million stars and is about 16,000 light-years away. This image spans an area on the sky equivalent to a grid of about 3 by 2 full Moons.

The ancient astronomer Ptolemy thought Omega Centauri was a star, and Edmond Halley identified it as a nebula in 1677. In the 1830s, John Herschel identified it as a globular star cluster orbiting the Milky Way Galaxy. A globular cluster is a spherical group of stars that are bound together by gravity.

Omega Centauri has always been the black sheep of globular clusters, since it has several characteristics that mark it as different from the typical globular cluster. For example, Omega Centauri is ten times more massive than other globular clusters. It also includes stars of a variety of ages, whereas other globular clusters contain stars from only one generation.

Recent research based on observations using NASA's Hubble Space Telescope and the Gemini Observatory indicates that there is a black hole at its center. This suggests that Omega Centauri may actually be a dwarf galaxy that has been stripped of its outer stars and not a globular cluster after all.

All four infrared detectors aboard WISE were used to create this mosaic image of Omega Centauri. The colors blue and cyan represent light emitted from stars at wavelengths of 3.4 and 4.6 microns. The green halo surrounding the center represents light at 12 microns, emitted by warm dust.

Image Source: /image/WISE/WISE2010-029

Curator: Wide-field Infrared Survey Explorer, Berkeley, CA, USA

Image Use Policy: Pulic Domain

Image Details

Image Type
Observation
Object Name
Omega Centauri Omega Cen NGC 5139
Subject - Milky Way
Star » Grouping » Cluster » Globular

Distance

Universescale1
16,000 light years
Wise_wise2010-029_128
 

Position Details

Position (ICRS)
RA = 13h 26m 53.7s
DEC = -47° 27’ 34.0”
Orientation
North is 153.2° CCW
Field of View
1.5 x 1.2 degrees
Constellation
Centaurus

Color Mapping

  Telescope Spectral Band Wavelength
Arrow_left_blue WISE Infrared (Near-IR) 3.4 µm
Arrow_left_cyan WISE Infrared (Near-IR) 4.6 µm
Arrow_left_green WISE Infrared (Mid-IR) 12.0 µm
Arrow_left_red WISE Infrared (Mid-IR) 22.0 µm
Spectrum_ir1
Arrow_top_blue
Arrow_top_cyan
Arrow_top_green
Arrow_top_red
Wise_wise2010-029_1280
×
ID
WISE2010-029
Subject Category
B.3.6.4.2.  
Subject Name
Omega Centauri, Omega Cen, NGC 5139
Credits
NASA/JPL-Caltech/UCLA
Lightyears
16,000
Redshift
-
Reference Url
/image/WISE/WISE2010-029
Type
Observation
Image Quality
Good
Distance Notes
Facility
WISE, WISE, WISE, WISE
Instrument
Color Assignment
Blue, Cyan, Green, Red
Band
Infrared, Infrared, Infrared, Infrared
Bandpass
Near-IR, Near-IR, Mid-IR, Mid-IR
Central Wavelength
3400, 4600, 12000, 22000
Start Time
Integration Time
Dataset ID
Notes
Coordinate Frame
ICRS
Equinox
J2000
Reference Value
201.7237070, -47.4594445
Reference Dimension
3906.0, 3084.0
Reference Pixel
1957.0, 1540.0
Scale
-0.000381945, 0.00038194457
Rotation
153.21
Coordinate System Projection:
TAN
Quality
Full
FITS Header
Notes
Creator (Curator)
Wide-field Infrared Survey Explorer
URL
http://wise.astro.ucla.edu
Name
Email
outreach@ssl.berkeley.edu
Telephone
Address
7 Gauss Way
City
Berkeley
State/Province
CA
Postal Code
94720
Country
USA
Rights
Pulic Domain
Publisher
Publisher ID
WISE
Resource ID
Resource URL
/image/WISE/WISE2010-029
Related Resources
Metadata Date
2011-08-05
Metadata Version
1.2
×

Detailed color mapping information coming soon...

 

×
Universescalefull
16,000 light years