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Fraser
2005-Jun-10, 04:30 PM
SUMMARY: In 1572, astronomer Tycho Brahe witnessed the supernova that created the stellar remnant Cassiopeia A. All that remains from this powerful explosion is a cloud of debris expanding away from a neutron star. New images from NASA's Spitzer space telescope show that this neutron star isn't out of action yet, though, in fact, it might have fired out a blast of energy 50 years ago, which is now lighting up the surrounding material. This recent activity might mean that the neutron star is actually an exotic magnetar, which regularly release bursts of gamma rays.

View full article (http://www.universetoday.com/am/publish/spitzer_view_dead_star.html)

What do you think about this story? Post your comments below.

antoniseb
2005-Jun-10, 04:36 PM
the remnant of a star that died in a supernova explosion 325 years ago

I am sometimes baffled at the lack of ability of people who write press releases to do basic math. 2005-1572 = 325?

Fraser
2005-Jun-10, 04:52 PM
Hey, yeah... 433. I'm glad I didn't ape that with my write up. :-)

om@umr.edu
2005-Jun-10, 05:18 PM
This is an important finding for those of us trying to decipher the birth of the solar system.

Like old soldiers, stars do not just die.

"We had thought the stellar remains inside Cassiopeia A were just fading away," said Dr. Oliver Krause, University of Arizona, Tucson.

"Spitzer came along and showed us this exploded star, one of the most intensively studied objects in the sky, is still undergoing death throes before heading to its final grave."

The question is whether all of the short-lived elements present at the birth of the solar system came from the supernova blast itself?

Or were some of these made afterward in the violent throes of the dying star?

We are confident that two species present at the birth of the solar system, Pu-244 and Fe-60, came from the supernova explosion itself.

Many of the others could have been made later. Age dating based on radioactive decay will not yield the same, concordant ages if the radioactive parents were produced at different times.

The record in meteorites will be different if some of the short-lived elements were made later in the final "death throes" of the supernova remnant.

Thanks, Fraser, for the news story.

With kind regards,

Oliver
http://www.umr.edu/~om

Greg
2005-Jun-12, 02:31 AM
Sometimes I do the same kind of thing with simple calculus problems. Was it the x or y intercept of that limit function?
It would be really nice if this turns out to be a magnetar. As I understood it, I thought most magnetars were found in the galactic buldge?
http://solomon.as.utexas.edu/~duncan/magne...Magnetic_Fields (http://solomon.as.utexas.edu/~duncan/magnetar.html#Strong_Magnetic_Fields)
This is a nice website with alot of material on magnetars. According to this a magnetar remenant should be visible to an x-ray detecting instrument. I would think tgat somebody has scanned the debris for x-ray emissions by now. The fact that a pulsar cannot be detected in the debris is in favor with the neutron star possibily being a magnetar, however.

Greg
2005-Jun-12, 02:41 AM
Looks like I answered my own question again. In fact, Cass A was the first thing that Chandra looked at. Indeed, the core object was quite visible in the x-ray spectrum. I will post a link to the article below.
http://www.space.com/scienceastronomy/astr...andra_pics.html (http://www.space.com/scienceastronomy/astronomy/chandra_pics.html)[SIZE=1][SIZE=1][SIZE=1]