Where have all the Cepheids gone, long time passing...

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RMSteele
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Where have all the Cepheids gone, long time passing...

Post by RMSteele »

Cepheid variable stars have proved to be important "standard candles" in estimating spatial distances. Now they are being used to plumb the depths of time as well. Recent findings indicate a huge volume of space near the galactic centre that is devoid of cepheids. The implication is that no stars have been born there for a few hundreds of millions of years, because cepheids run through their lifetimes much more quickly than our relatively low mass Sun (and pass through the helium burning Cepheid instability phase in mere tens of millions of years after their formation). This means that the stars in the "wot no cepheids" region represents a static old stellar population. Any ideas why? Incidentally it seems to me that this region matches the region of the galaxy's central bar.
RMSteele
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Re: Where have all the Cepheids gone, long time passing...

Post by RMSteele »

Brian, please can you move this to the Astrophysics section? Thanks
Bob
Brian
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Re: Where have all the Cepheids gone, long time passing...

Post by Brian »

Done :)
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Cliff
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Re: Where have all the Cepheids gone, long time passing...

Post by Cliff »

Dear Bob
I think there's an article (The Earth Next Door) in 27th August New Scientist magazine that might be of interest - I've only glanced through it as yet so hesitate to comment in case I get things wrong. If I read it properly I might say more about it. But I sometimes think it best to be cautious about some things in NS ?
Best wishes from Cliff
PS : - SORRY I'M NOT SURE WHAT WENT WRONG BUT THE ABOVE IS IN THE WRONG LOCATION - Cliff
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