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Fraser
2008-Feb-12, 10:50 PM
At some point in the last year or so, the Sun-like star tau Bootis completely flipped its magnetic field. The star's north pole became its south pole, and vice versa. It this going to happen to our own Sun? Yes! Don't panic though; in fact, it happens every 11 years or so.

More... (http://www.universetoday.com/2008/02/12/star-flips-its-magnetic-field/)

Noclevername
2008-Feb-13, 01:24 AM
It must be 2012 there. :D

Jerry
2008-Feb-13, 02:48 AM
...Perhaps the star fipped over, and its magnetic field remained stable;) Which brings up the question, what should define the orientation of a gaseous object: Collective momentum, or collective field strength?

rtomes
2008-Feb-13, 10:47 AM
At some point in the last year or so, the Sun-like star tau Bootis completely flipped its magnetic field. The star's north pole became its south pole, and vice versa. It this going to happen to our own Sun? Yes! Don't panic though; in fact, it happens every 11 years or so.

More... (http://www.universetoday.com/2008/02/12/star-flips-its-magnetic-field/)
Hey that must be a cycle, I like cycles.

Actually "flip" is not quite the right word for it. Rather, the N and S parts of the Sun become shaped like the two halves of a tennis ball (actually they are always a bit like that, but they become more so). Then the two N poles slip past the two S poles and join up again at the other side. So there is never an E pole and an W pole although there may be four of these.

geonuc
2008-Feb-13, 11:07 AM
Why hasn't this been observed with other stars before? Is it hard to detect?

trinitree88
2008-Feb-13, 05:49 PM
Why hasn't this been observed with other stars before? Is it hard to detect?

geonuc. Well the sun is a star too and its' flip of ~ 11 years is close to but not in exact agreement with the period of it's largest planet, Jupiter, so if Tau Boo b has a period of ~ 3.1 days, it'd be very poignant to check for a very short sunspot cycle....of the order of 3.1 days. The original article reference isn't too specific about the length of the observation...only that sometime within a few years it was noticed to have changed. Interesting. pete

rtomes
2008-Feb-13, 09:49 PM
Why hasn't this been observed with other stars before? Is it hard to detect?
Cycles like the sunspot cycle have been detected in other stars for some time. Maybe what is new is that the actual magnetic field was somehow detected. That would be a bit trickier thing to measure I expect.

geonuc
2008-Feb-14, 12:29 PM
geonuc. Well the sun is a star too and its' flip of ~ 11 years is close to but not in exact agreement with the period of it's largest planet, Jupiter, so if Tau Boo b has a period of ~ 3.1 days, it'd be very poignant to check for a very short sunspot cycle....of the order of 3.1 days. The original article reference isn't too specific about the length of the observation...only that sometime within a few years it was noticed to have changed. Interesting. pete
Not sure what poignancy has to do with my question, but thanks for letting me know the sun is a star. I had no idea.


Cycles like the sunspot cycle have been detected in other stars for some time. Maybe what is new is that the actual magnetic field was somehow detected. That would be a bit trickier thing to measure I expect. Yeah, that was what I wanted to know - is detecting the magnetic field of a star (other than the sun) difficult?

Nadme
2008-Feb-14, 01:30 PM
Flip it! Flip it good! :lol:

Have known this info before, including about Sol.

This is further proof that stars are groovy.