B Detecting Unusual Stellar Shapes: Looking for Perturbed Planets

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When searching for exoplanets, the assumption that stars are perfect spheres is generally valid, as most stars are only slightly oblate due to rotation. The shape of a star does not significantly impact the detection of orbiting bodies, as the laws of physics are consistent across the universe. Pulsations in stars can affect measurements, but their patterns differ from those caused by planets, allowing for differentiation. If a star's chaotic behavior complicates detection, astronomers may choose to avoid it. Overall, the methods used for detecting planets, such as transit and Doppler, remain effective despite these considerations.
wolram
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How can we be sure that when looking for planets there sun is not a perfect sphere and just looks like it is being perturbed by a gravitating body?
 
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The star is usually not assumed to be a perfect sphere ... the shape of stars is determined by physics that are well known.
Most stars would be oblate due to their rotation ... but only slightly so a sphere is a very good approximation - especially considering the distances involved.
We can be sure of this for distant stars the same way we can be sure of anything - we check for nearby stars, and assume that the laws of physics are pretty much the same everywhere.

However the shape of the star is not important for detecting bodies orbiting it.

http://www.planetary.org/explore/sp...anets.html?referrer=https://www.google.co.nz/
You can have a go working out how far off spherical the star would have to be to give it the appearance of the kinds of wobbles measured.
 
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Pulsations of stars are indeed something that can mess up radial velocity and intensity measurements, but those pulsations don't have the same structure as influences of planets, so it is possible to separate them. In the worst case you just stop looking for planets around a star that is too chaotic.
 
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wolram said:
How can we be sure that when looking for planets there sun is not a perfect sphere and just looks like it is being perturbed by a gravitating body?
Are you referring to detection by the transit or Doppler method?
 

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