TITLE: GCN CIRCULAR NUMBER: 14844 SUBJECT: GRB 130610A: Skynet/PROMPT detection of the optical afterglow DATE: 13/06/10 03:57:35 GMT FROM: Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet A. Trotter, J. Haislip, A. LaCluyze, D. Reichart, T. Berger, M. Carroll, H. T. Cromartie, R. Egger, A. Foster, C. Foster, N. Frank, K. Ivarsen, D. James, M. Maples, J. Moore, M. Nysewander, E. Speckhard, P. Taylor and J. A. Crain report Skynet observed the Swift/XRT localization of GRB 130610A (Cummings et al., GCN 14842, Swift trigger #557845), starting at 2013-06-10, 03:14:05 UT (t=2.03m post-trigger), with three 16" telescopes of the PROMPT array at CTIO, Chile. We detect a fading afterglow in B, V and I bands at: RA = 14:57:40.9, Dec = 28:12:25.5 (J2000.0), consistent with the UVOT source position reported in GCN 14842. The afterglow rises until t~3.4m, at which time the apparent magnitudes are B~18.1, V~17.1, I~16.6. A preliminary light curve is at: http://www.skynet.unc.edu/grb/grb130610a.png Magnitudes are in the Vega system and photometry is calibrated to 4 SDSS stars in the field. Skynet observations are ongoing.