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The Question
(Submitted November 12, 1998)
I read that Polaris may be reclassified as a different type of star soon.
Is that true, and if so, what is the new classification?
The Answer
Polaris is a known Cepheid variable star with a period of 4 days, however,
during the last decade, the amplitude of its brightening and fading has
decreased precipitously to less than 0.1 magnitude as compared to the 1.5
magnitude swings that usually characterize Cepheid variable stars with
this
same 4 day period. An extrapolation suggested that it would stop pulsing
sometime earlier
this year. However, it did not stop.
Also, the Canadian magazine of astronomy & stargazing "SkyNews" had an
article in its March/April 1998 issue titled:
"The Polaris Beat"
The North Star, the nearest Cepheid variable star, hasn't been
behaving itself, and Canadian astronomers are trying to find out why.
You have to subscribe to read the article, though...
See also:
http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970410c.html
I hope this helps.
Karen Smale, Mike Arida, David Palmer, and Tim Kallman
for Ask a High-Energy Astronomer
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