American Association of Variable Star Observers (AAVSO)
Sat, 01/14/2023 - 00:50

The eclipsing nova-like variable BH Lyn is in a rare low state. VSX has the range at 13.6-16.3 in B and I've observed this star fairly often, and it's been pretty consistently at CV ~ 15.3 mag normally and dropping to ~17.0 during the eclipse. At JD 2459956.60860 I measured it at v = 17.57(10) when it was at phase 0.53, making it more than 2 magnitudes fainter than it normally is out of eclipse. The prior day I had attempted to make observations of an eclipse but the star became too faint before it reached mid-eclipse. My faintest measurement was CV = 18.53(24). 

The ~25 year history for this star in the LCG does not appear to show a similar low state. The star appears to have been pretty consistent at v ~ 17 during eclipse and v ~ 15 when not in eclipse. The eclipse range during this low state is probably somewhat less than the typical two magnitudes, so it's probably not getting fainter than 19 if anyone has a clear night.

Shawn (DKS)