This week we investigate the (rather boring looking) light curve of the star BD+65 1636. It is classified as a young stellar object with a spectral type of B8, so a rather massive star. The distance based on Gaia data is just over 300pc. It is situated on the sky very close to the cluster NGC7129. The cluster itself, however, seems to be at a distance of about 1kpc, i.e. three times further away. Hence, this object is just projected onto the cluster, but not a member of it.

The light curve of the star is to a large extend unspectacular. The colours of the star are such, that we shifted the V and I magnitudes by plus/minus 0.3mag, respectively, to improve visibility. There are outlier data points which are all explainable by photometry errors, saturation, non-linearity and colour terms. There are however, some long term trends in the brightness at the level of a few percent. In particular the I-Band magnitude drops by 3 percent over the more than 4 years worth of data.