We have obtained radial velocity measurements for stars in two widely separated fields in the Anticenter Stream.udCombined with SDSS/USNO-B proper motions, the new measurements allow us to establish that the stream isudon a nearly circular, somewhat inclined, prograde orbit around the Galaxy. While the orbital eccentricity is similarudto that previously determined for the Monoceros stream, the sizes, inclinations, and positions of the orbits forudthe two systems differ significantly. Integrating our best-fitting Anticenter Stream orbit forward, we find that itudis closely aligned along and lies almost on top of a streamlike feature previously designated the “Eastern BandedudStructure.” The position of this feature coincides with the apogalacticon of the orbit. We tentatively concludeudthat this feature is the next wrap of the Anticenter Stream.
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