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
More Information
Supernovas & Supernova Remnants
Related Podcasts
Quick Look: When a Stable Star Explodes
Download Image

More Information

More Images
Temperature Map of Cassiopeia A
(Credit: NASA/CXC/MIT/UMass Amherst/M.D.Stage et al.)

Animation & Video

More Releases
Cassiopeia A
Cassiopeia A
(21 Apr 21)
Cassiopeia A
Cassiopeia A
(26 Aug 19)
Cassiopeia A
Cassiopeia A
(12 Dec 17)
Cassiopeia A
Cassiopeia A
(15 Nov 13)
Cassiopeia A
Cassiopeia A
(29 Mar 12)
Cassiopeia A
Cassiopeia A
(23 Feb 11)
Cassiopeia A
Cassiopeia A
(04 Nov 09)
Cassiopeia A
Cassiopeia A
(06 Jan 09)
Cassiopeia A
Cassiopeia A
(06 Jan 09)
Cassiopeia A
Cassiopeia A
(13 Jun 05)
Cassiopeia A
Cassiopeia A
(23 Aug 04)
Cassiopeia A
Cassiopeia A
(19 Aug 02)
Cassiopeia A
Cassiopeia A
(27 Jun 00)
Cassiopeia A
Cassiopeia A
(21 Dec 99)
Cassiopeia A
Cassiopeia A
(26 Aug 99)

Related Images
Cassiopeia A:
Chandra Discovers Relativistic Pinball Machine

Cassiopeia A
Credit: NASA/CXC/MIT/UMass Amherst/M.D.Stage et al.

This extraordinarily deep Chandra image shows Cassiopeia A (Cas A, for short), the youngest supernova remnant in the Milky Way. New analysis shows that this supernova remnant acts like a relativistic pinball machine by accelerating electrons to enormous energies. The blue, wispy arcs in the image show where the acceleration is taking place in an expanding shock wave generated by the explosion. The red and green regions show material from the destroyed star that has been heated to millions of degrees by the explosion.

Astronomers have used this data to make a map, for the first time, of the acceleration of electrons in a supernova remnant. Their analysis shows that the electrons are being accelerated to almost the maximum theoretical limit in some parts of Cas A. Protons and ions, which make up the bulk of cosmic rays, are expected to be accelerated in a similar way to the electrons. Therefore, this discovery provides strong evidence that supernova remnants are key sites for energizing cosmic rays.

Charged particles are believed to scatter or bounce off tangled magnetic fields in the shock wave, which act like bumpers in a pinball machine. When the particles cross the shock front they are accelerated, as if they received a kick from a flipper in a pinball machine. Typically it should take a few hundred scatterings off the shock's magnetic field before the particles cross the shock front. It then takes about 200 crossings of the shock front to accelerate the particles seen in the Chandra data. Scientists estimate it would take about 200 years -- over half the age of the remnant -- to accelerate electrons to cosmic ray energies in the slowest parts of the shocks, but only about 50 years to accelerate the highest energy electrons in the regions of maximum acceleration.

Fast Facts for Cassiopeia A:
Credit  NASA/CXC/MIT/UMass Amherst/M.D.Stage et al.
Scale  Image is 7.3 x 6.4 arcmin
Category  Supernovas & Supernova Remnants
Coordinates (J2000)  RA 23h 23m 26.7s | Dec +58° 49' 03.00"
Constellation  Cassiopeia
Observation Dates  Nine observations in 2004: Feb 8, Apr 14, 18, 20, 22, 25 28, May 01, 05
Observation Time  11 days, 14 hours
Obs. IDs  4634-4639, 5196, 5319-5320
Color Code  Energy (Red: 0.5-1.5 keV; Green: 1.5-2.5; Blue 4.0-6.0)
Instrument  ACIS
Also Known As Cas A
References Cosmic-ray diffusion near the Bohm limit in the Cassiopeia A supernova remnant, M.D. Stage et al., Nature Physics, Volume 2, Issue 9, p. 614 (2006)
Distance Estimate  About 11,000 light years
Release Date  November 15, 2006