TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4561 SUBJECT: GRB 060121: candidate optical counterpart DATE: 06/01/22 12:55:46 GMT FROM: Daniele Malesani at SISSA-ISAS,Trieste,Italy D. Malesani (SISSA/ISAS), L.A. Antonelli (INAF/OAR), S. Covino (INAF/OABr), E. Palazzi (INAF/IASF Bo), G. Andreuzzi (INAF/TNG), and G. Tessicini (INAF/TNG), report on behalf of a larger Italian collaboration: We observed the field of GRB 060121 (Arimoto et al., GCN 4550; Prigozhin et al., GCN 4551; Boer et al., GCN 4552) at two epochs with the Italian TNG telescope located in the Canary Islands. Photometry was performed in the R-band starting on Jan 22.021 UT (Antonelli et al., GCN 4556) and Jan 22.193 UT (2.1 and 6.2 h after the GRB, respectively). The second run provided images of lower quality, due to bad observing conditions. Inside the XRT error circle (Mangano et al., GCN 4560), we see a faint source which is detected in our first dataset but is not detected in the second epoch (which is, however, shallower). The coordinates are (J2000): alpha = 09:09:51.93 delta = +45:39:45.4 We estimate an error of about 0.5" (mainly due the low S/N of the object). Even if at the moment we do not makeany claim of variability, we suggest this object may be the optical counterpart of GRB 060121. This message can be cited.