Presentation #311.01 in the session The Milky Way.
We present observational data that reveal the extreme evolution of an object known as X7, an elongated dust and gas feature, presently located half an arcsecond from the Galactic Center supermassive black hole. The observations cover two decades of high-angular-resolution near-infrared data from the W. M. Keck Observatory using both spectro-imaging observations of Br-γ line emission and Lp (3.8 μm) imaging data. The analysis provides the first estimate of X7’s orbital parameters and quantitative characterization of the evolution of its morphology and mass. The leading edge of X7 appears to be on a mildly eccentric (e ∼ 0.3), relatively short-period (170 yr) orbit and is headed toward periapse passage, estimated to occur in ∼2036. Over the course of our observations, X7 has (1) become more elongated, with a current length-to-width ratio of 9, (2) maintained a very consistent long-axis orientation (position angle of 50°), (3) inverted its radial velocity differential from tip to tail from −50 to +80 km s−1, and (4) sustained its total brightness (12.8 Lp magnitudes at the leading edge) and color temperature (425 K).