Using the POLISH instrument , I am unable to reproduce the large-amplitude polarimetric observations of Berdyugina et al .
( 2008 ) to the > 99.99 \% confidence level .
I observe no significant polarimetric variability in the HD 189733 system , and the upper limit to variability from the exoplanet is \Delta P < 7.9 \times 10 ^ { -5 } with 99 % confidence in the 400 nm to 675 nm wavelength range .
Berdyugina et al .
( 2008 ) report polarized , scattered light from the atmosphere of the HD 189733b hot Jupiter with an amplitude of two parts in 10 ^ { 4 } .
Such a large amplitude is over an order of magnitude larger than expected given a geometric albedo similar to other hot Jupiters .
However , my non-detection of polarimetric variability phase-locked to the orbital period of the exoplanet , and the lack of any significant variability , shows that the polarimetric modulation reported by Berdyugina et al .
( 2008 ) can not be due to the exoplanet .