Images by Date
Images by Category
Solar System
White Dwarfs
Neutron Stars
Black Holes
Milky Way Galaxy
Normal Galaxies
Galaxy Clusters
Cosmology/Deep Field
Images by Interest
Space Scoop for Kids
Sky Map
Photo Blog
Top Rated Images
Image Handouts
Fits Files
Image Tutorials
Photo Album Tutorial
False Color
Cosmic Distance
Look-Back Time
Scale & Distance
Angular Measurement
Images & Processing
Image Use Policy
Web Shortcuts
Chandra Blog
RSS Feed
Email Newsletter
News & Noteworthy
Image Use Policy
Questions & Answers
Glossary of Terms
Download Guide
Get Adobe Reader
W28: A Mixed Bag

When some stars die, they explode as supernovas and their debris fields (aka, "supernova remnants") expand into the surrounding environments. There are several different types, or categories, of supernova remnants. One of these is known as a mixed-morphology supernova remnant. This type gets its name because it shares several characteristics from other types of supernova remnants. More specifically, particles that have been superheated are seen in X-rays in the center of the remnant. This inner region is enclosed by shell structure detected in radio emission.

This composite shows a classic example of mixed-morphology supernova remnant known as W28. Each wavelength shows detailed structure of how the supernova shock wave is interacting, or has interacted, with the complex cloudy environment which surrounded its parent star. In this image, the stars and fine structure in the background are seen in optical light (grey and white) by the Cerro Tololo Inter-American Observatory in Chile. The radio (orange) data were obtained by the Very Large Array in New Mexico, while the blue in the wide-field view comes from the ROSAT satellite (X-rays). Data from NASA’s Chandra X-ray Observatory give new detail into the heart of W28 as seen in the inset. In this close-up view of the center, low-energy X-rays are colored red, the medium are green, and the highest found by Chandra are blue. The Chandra data show the shape and extent of the high-energy emission in the central region. By studying W28 and others like it, astronomers hope to better understand the complexities involved when a star explodes in a crowded neighborhood.

Involved in this W28 study were Jonathan Keohane (Hampden-Sydney College), Jeonghee Rho (Spitzer Science Center), Thomas Pannuti (Morehead State University), Kazik Borkowski (North Carolina State University) and Frank Winkler (Middlebury College).

Fast Facts for W28:
Credit  Chandra X-ray: NASA/CXC/HSC/J. Keohane et al.; ROSAT X-ray: NASA/ROSAT; Optical: NOAO/CTIO/P.F. Winkler et al.; Radio: NSF/NRAO/VLA/G. Dubner et al.
Release Date  June 02, 2008
Scale  Left panel: 54 arcmin across; Chandra inset: 24.7 arcmin across
Category  Supernovas & Supernova Remnants
Coordinates (J2000)  RA 18 00 24.80 | Dec -23° 25´ 40.30"
Constellation  Sagittarius
Observation Date  October 12, 2002
Observation Time  24 hours
Obs. ID  2828
Instrument  ACIS
References Rho Borkowski, 2002, ApJ, 575, 201
Color Code  Chandra (Low-energy X-rays are red, Medium are green, High are blue); ROSAT X-ray (Blue); Optical (Grey); Radio (Orange).
Distance Estimate  About 6,000 light year
distance arrow
Visitor Comments (0)
Rate This Image

Rating: 3.8/5
(490 votes cast)
Download & Share


1024x768 - 698.1 kb
1280x1024 - 1015.1 kb
1680x1050 - 1 MB
More Information
More Images
Chandra X-ray Image
of W28
Jpg, Tif

More Images
Animation & Video
Multiwavelength W28

More Animations
Related Images
(02 June 04)

(14 Dec 04)

Crab Nebula
Crab Nebula
(24 Oct 06)

Related Information
Related Podcast
Top Rated Images
Timelapses: Crab Nebula and Cassiopeia A

Chandra Releases 3D Instagram Experiences

Brightest Cluster Galaxies