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We report new infrared measurements of the supermassive black hole at theGalactic Center, Sgr A*, over a decade that was previously inaccessible atthese wavelengths. This enables a variability study that addresses variabilitytimescales that are ten times longer than earlier published studies. Sgr A* wasinitially detected in the near-infrared with adaptive optics observations in2002. While earlier data exists in form of speckle imaging (1995 - 2005), SgrA* was not detected in the initial analysis. Here, we improved our speckleholography analysis techniques. This has improved the sensitivity of theresulting speckle images by up to a factor of three. Sgr A* is now detectablein the majority of epochs covering 7 years. The brightness of Sgr A* in thespeckle data has an average observed K magnitude of 16.0, which corresponds toa dereddened flux density of $3.4$ mJy. Furthermore, the flat power spectraldensity (PSD) of Sgr A* between $\sim$80 days and 7 years shows itsuncorrelation in time beyond the proposed single power-law break of $\sim$245minutes. We report that the brightness and its variability is consistent over22 years. This analysis is based on simulations using Witzel et al. (2018)model to characterize infrared variability from 2006 to 2016. Finally, we notethat the 2001 periapse of the extended, dusty object G1 had no apparent effecton the near-infrared emission from accretion flow onto Sgr A*. The result isconsistent with G1 being a self-gravitating object rather than a disrupting gascloud.

Consistency of the Infrared Variability of Sgr A* over 22 years