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Article: Cosmic ray font: supernova remnants rev up ions.(This Week)
- Article from:
- Science News
- Article date:
- October 1, 2005
- Author:
CopyrightCOPYRIGHT 2005 Science Service, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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In 1572, the Danish astronomer Tycho Brahe created a sensation when he reported that a star suddenly appeared in the sky, blazing brighter than Venus, and then faded from view. Tycho's "new star" was in fact a supernova, an exploding old star. More than 4 centuries later, observations of the remnant of Tycho's supernova are still revealing information to astronomers. High-resolution X-ray images now offer evidence that shock waves from that and other supernovas generate most of the cosmic rays that bombard Earth.
X-ray images taken a decade ago showed that shock waves from supernova remnants can accelerate electrons to cosmic ray energies, but electrons make up ...