TITLE: GCN CIRCULAR NUMBER: 10112 SUBJECT: GRB 091018: Skynet/PROMPT Observations of Possible Host Galaxy DATE: 09/10/30 04:17:19 GMT FROM: Aaron LaCluyze at U.North Carolina A. LaCluyze, D. Reichart, J. Haislip, K. Ivarsen, R. Egger, A. Foster, J. Moore, A. Oza, M. Schubel, J. Styblova, A. Trotter, J. A. Crain, and M. Nysewander report: Skynet has continued to observed the afterglow (Stamatikos et al., GCN 10034) of GRB 091018 (Stamatikos et al., GCN 10034) with two of the 16" PROMPT telescopes at CTIO in RI (LaCluyze et al., GCNs 10046, 10061). Between 3.2 and 7.5 days after the trigger, the light curve is consistent with constant emission, which suggests that we are observing the host galaxy. If so, we measure its brightness to be: R = 22.30 +/- 0.11 (statistical) +/- 0.56 (systematic; calibrated to 115 USNO B1 stars). and I = 21.78 +/- 0.16 (statistical) +/- 0.54 (systematic; calibrated to 67 USNO B1 stars).