Using approximately 1.3 fb-1 of D0 data, we observe a new state decaying into Upsilon(1S)+gamma, where the Upsilon(1S) meson is detected by its decay into a pair of oppositely charged muons, and photon is identified by reconstructing the electron-positron pair produced by its conversion in the detector. The significance of this state is at least six standard deviations, and its mass is centered at 10.551 +/- 0.014(stat.) +/- 0.017(syst.) GeV/c2, consistent with that of the structure recently discovered by the ATLAS Collaboration.