Affiliation
American Association of Variable Star Observers (AAVSO)
Thu, 03/08/2018 - 00:29
Bart Staels (Belgium) reports that the T Tau / UXOR star SU Aur is undergoing a fade, with the AAVSO light curve showing a fading across all wavebands. The fact that SU is physically involved with its neighbour AB Aur (itself going through an active bright phase at the moment) highlights the need for continued monitoring of these two objects together. SU has a high orbital inclination suggesting that fades are the result of planetesimal transits. Both stars may be observed - in fact are best observed - with small telescopes, even large binoculars. Telescopic observers should note also that in the same field is another similar star GM Aur.
Well, it's obvious that there was a fade in the end of January. However last night SU Aur was around 9.4TG - much brighter than on my reference images. I'll make proper photometry later...
Clear skies,
Robert
The fade Mike is referring to is indeed the one in the end of Januari. It is the deepest recorded fade of SU Aur (normally the drop in light is not more then 0.8 magnitude, this time it was around 1.2). The lightcurve also shows a "shoulder" or plateau before and after the dimming.
SU Aur continues to be faint. Bart has provided me with several multi-colour curves which will take a while to analyse! In which connection I would also say that its bright neighbour AB Aur (and also possibly GM nearby which I assume is part of the same association-within-an-association) should be monitored. Another (much fainter) object in the same area is GZ Aur which may also bear watching. And still in the same region is RW Aur, continuing to do weird things!