Research team member Veli-Pekka Hentunen measured the lightcurves of the HAT-P-3b and TrES-2b 26./27.2.2008 at Taurus Hill Observatory. He used clear filter for both measurement and the exposure times were 90 sec. The weather was quite foggy and the objects were quite low in the norhtern sky (about 20 to 30 degrees). The unfavourable seeing made the measurements challenging.

Observer: Veli-Pekka Hentunen

In the HAT-P-3b measurement the comparison star was GSC 3466-1158 (C1) and the check star was GSC 3466-1226 (C2). Veli-Pekka started the mesurements just after the dark time started in the Finland, about at the 19:00 finnish time. Due this, the beginning of the transit was missed.

In the TrES-2b measurement the used comparison star was GSC 3549-2716 (C1) check star was GSC 3549-2704 (C2). Veli-Pekka started the measurements a bit too late (?) and due that the beginning of the transit is not measured as accurate as desired. The catalogs said that the transit should have started 21:00 (UT). But the midtransit time 21:50 (UT) (Julian day 2454523.41) that was stated in the catalogs was accordingly to Veli-Pekka’s measurements a bit earlier than predicted.