Images by Date
Images by Category
Solar System
Stars
White Dwarfs
Supernovas
Neutron Stars
Black Holes
Milky Way Galaxy
Normal Galaxies
Quasars
Galaxy Clusters
Cosmology/Deep Field
Miscellaneous
Images by Interest
Space Scoop for Kids
Multiwavelength
Sky Map
Constellations
3D Wall
Photo Blog
Top Rated Images
Image Handouts
Desktops
High Res Prints
Fits Files
Image Tutorials
Photo Album Tutorial
False Color
Cosmic Distance
Look-Back Time
Scale & Distance
Angular Measurement
Images & Processing
AVM/Metadata
Getting Hard Copies
Image Use Policy
Web Shortcuts
Chandra Blog
RSS Feed
Chandra Mobile
Chronicle
Email Newsletter
News & Noteworthy
Image Use Policy
Questions & Answers
Glossary of Terms
Download Guide
Get Adobe Reader
More Information
Groups & Clusters of Galaxies
X-ray Astronomy Field Guide
Groups & Clusters of Galaxies
Questions and Answers
Groups & Clusters of Galaxies
Chandra Images
Groups & Clusters of Galaxies
Related Podcasts
A Tour of Perseus
A Tour of Perseus (2014-06-25)
Download Image

More Information
Handout
Handout: html | pdf

More Images
Chandra X-ray Image
of Stephan's Quintet,
Close-up
(Credit: NASA/CXC/INAF-Brera/
G.Trinchieri et al.)

More Releases
Stephan's Quintet

Related Images
HCG 62
HCG 62
(05 Mar 01)
Stephan's Quintet:
Intruder Galaxy Shocks Tightly-Knit Group


Stephan's Quintet
Credit: X-ray: NASA/CXC/INAF-Brera/G.Trinchieri et al.; Optical: Pal.Obs. DSS

The hurly-burly interactions in the compact group of galaxies known as Stephan's Quintet are shown in the upper left where a Chandra X-ray Observatory image (blue) is superimposed on a Digitized Sky Survey optical image (yellow). Shock-heated gas, visible only with an X-ray telescope, appears as a bright blue cloud oriented vertically in the middle of the image and has a temperature of about 6 million degrees Celsius. The heating is produced by the rapid motion of a spiral galaxy intruder located immediately to the right of the shock wave in the center of the image (galaxy labeled B in the wide field optical image on the lower right).

Stephan's Quintet is an excellent example of the tumultuous dynamics of a compact group. The motion of the galaxies through the hot gas, and the gravitational pull of nearby galaxies are stripping cool gas from the galaxies, thereby depriving them of the raw material from which to form new stars. In a few billion years the spiral galaxies in Stephan's Quintet will likely be transformed into elliptical galaxies.

During the past few billion years additional gas may have been stripped from the galaxies in the group and heated by collisions such as the one seen in these images. An intruder that may have passed through the center of the group at least twice is the faint galaxy C seen in the wide field optical image. The fainter blue cloud in the X-ray/optical image may be a relic of past collisions.

The four galaxies A, B, D and E strung out diagonally across the wide field optical image are at a distance of about 280 million light years from Earth. The large-appearing galaxy F in the lower left of this image has now been identified as a foreground galaxy at a distance of about 35 million light years, leaving the group originally identified as Stephan's Quintet with only a quartet of galaxies. However, if we include galaxy C, which is at the same distance as the other four galaxies, it becomes a quintet again!

Ginevra Trinchieri of the INAF-Brera Observatory in Milan, Italy, Jack Sulentic of the University of Alabama in Tuscaloosa, and Dieter Brietschwerdt and Wolfgang Pietsch of the Max-Planck Institute for Extraterrestrial Physics in Garching, Germany are co-authors of a paper that describes the Chandra data on Stephan's Quintet. The paper will appear in an upcoming issue of the journal Astronomy & Astrophysics.

Fast Facts for Stephan's Quintet:
Credit  X-ray: NASA/CXC/INAF-Brera/G.Trinchieri et al.; Optical: Pal.Obs. DSS
Scale  Composite (upper left) = 2.9 x 2.3 arcmin,
Wide field (lower right) = 7 x 7 arcmin
Category  Groups & Clusters of Galaxies
Coordinates (J2000)  RA 22h 36m 00.00s | Dec +33° 59’ 00.00"
Constellation  Pegasus
Observation Dates  July 09, 2000
Observation Time  6 hours
Obs. IDs  789
Color Code  X-ray (blue); Optical (yellow)
Instrument  ACIS
Also Known As HCG 92
References G. Trinchieri et al. Astro-ph/0302590
Distance Estimate  280 million light years (redshift z = 0.02)
Release Date  May 08, 2003