TITLE: GCN CIRCULAR NUMBER: 16570 SUBJECT: GRB 140710A: Gemini-N redshift of likely host DATE: 14/07/10 15:44:55 GMT FROM: Nial Tanvir at U.Leicester N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick) and D. Coulson (Gemini) report: We observed the position of GRB 140710A (Siegel et al. GCN 16563; Tanga et al. GCN 16565/6; Cenko et al. GCN 16567; Butler et al. GCN 16568) with the GMOS-N spectrograph on Gemini-North. Observations began at 14:06 UT, approximately 3.8 hr post burst. The spectrum shows a faint continuum and emission lines of OII (3727), Hbeta (4863) and OIII (4959/5007) at a common redshift of z=0.558. There is also some evidence for a 4000A break at the same redshift. Given the fading nature already reported, and the slight extension of the source in the acquisition images, it is very likely that this is the redshift of the GRB host galaxy, and that it is already comparable to the afterglow brightness.