k.camplate wrote:
>With the new planets being discovered, have they all been in basically the
>same axis as our solar system? How is our system orientated with respect to
>the rotation of the galaxy? I think that the way they 'discover' other
>planets is from its sun's wobble towards and away from us as that planets
>circles the sun.
Yes, the wobble method is used. They look for doppler shifting of
the stars light in a periodic manner. The problem with doppler shift
is that there could be other mechanisms that cause the wavelength of
stars light to shift in such a way to mimic the effect of a planet
induced wobble.
As for orientation, we can't determine the orientation. In other
words, the system might be edge-on to us in which case we see the
full wobble, or the system might not be in perfect alignment so we're
only seeing part of the wobble.
>Can we detect stars that wobble up and down yet, or in some way?
Yes we can detect up-and-down motion (or side-to-side) of stars with
the European Space Agency's Hipparcos satellite
(http://astro.estec.esa.nl/Hipparcos/). As for wobble induced by
planets, Hipparcos would only be able to detect cases where the
planets have orbits longer than 10 days.
The October 28 issue of ScienceNews had a short article on the
question of whether extrasolar planets are really brown dwarfs
(http://www.sciencenews.org/20001028/fob3.asp). It discusses the
issue of doppler shift and observed wobble in a bit more detail.
Jeff
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http://www.netjeff.com/
