The answer to your question is a matter of perspective. First off, all stars (including our Sun) are variable to some small extent. However, this variability may not be detectable using typical amateur equipment. The short answer is no, all binary stars are not variable stars from our vantage point on Earth. Only when the orbital inclination of a binary system is favorably positioned, then a fraction of each may be visually obscured on a periodic basis resulting in a decrease in the overall brightness of the system.. This can be used to define the orbital period which can be as short as a few hours or in some cases as long as months or years. As far as I know, only stars that exhibit some sort of variability are maintained in their archives. This includes host stars for exoplanet systems which may only vary by fractional percentage (<<1%) changes in overall brightness.
I have been running some .FITS files in NASA's Exoplanet Transit Interpretation Code (EXOTIC) which links to the AAVSO database to obtain star charts and getting error messages when inputting certain host stars (mostly binaries with exoplanets in Circumbinary orbits e.g Kepler 1647, 35, 453 etc, hence my question.
Scott who works with the MAST database pointed me to the TESS Eclipsing Binary Survey https://tessebs.villanova.edu...it's quite resourceful.
The answer to your question is a matter of perspective. First off, all stars (including our Sun) are variable to some small extent. However, this variability may not be detectable using typical amateur equipment. The short answer is no, all binary stars are not variable stars from our vantage point on Earth. Only when the orbital inclination of a binary system is favorably positioned, then a fraction of each may be visually obscured on a periodic basis resulting in a decrease in the overall brightness of the system.. This can be used to define the orbital period which can be as short as a few hours or in some cases as long as months or years. As far as I know, only stars that exhibit some sort of variability are maintained in their archives. This includes host stars for exoplanet systems which may only vary by fractional percentage (<<1%) changes in overall brightness.
Kevin
Hi Kevin,
I guess variability is a matter timing then?
I have been running some .FITS files in NASA's Exoplanet Transit Interpretation Code (EXOTIC) which links to the AAVSO database to obtain star charts and getting error messages when inputting certain host stars (mostly binaries with exoplanets in Circumbinary orbits e.g Kepler 1647, 35, 453 etc, hence my question.
Scott who works with the MAST database pointed me to the TESS Eclipsing Binary Survey https://tessebs.villanova.edu...it's quite resourceful.
Thanks for your reply.
AAVSO has an eclipsing binary section:
https://www.aavso.org/aavso-eclipsing-binaries-section
Ray
Thanks Ray.