TITLE: GCN GRB OBSERVATION REPORT NUMBER: 609 SUBJECT: GRB 000307, Optical Observations DATE: 00/03/11 07:48:51 GMT FROM: Jonathan Kemp at Biosphere 2 Ctr/Columbia U J. Kemp & J. P. Halpern (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team: "We observed the entire IPN error box of GRB 000307 (Hurley et al. GCN #601) in the R band using the MDM 1.3m telescope starting on March 10.12 UT, and again on March 11.12 UT. One hour of exposure was obtained on each night in seeing of approximately 1".4. No new object is apparent above the limit of the digitized POSS-II plate, and no variable object is detected brighter than an approximate limiting magnitude of R = 21.7. These observations were severely affected by scattered light from the star Betelgeuse, which is only 0.6 degrees away, making precise photometry difficult. We also note that Galactic extinction in this direction is significant, with E(B-V) = 0.445 according to Schlegel et al. (1998), corresponding to A_R = 1.19. This message may be cited."