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NGC 5273 is a known optical and X-ray variable AGN. We analyze new andarchival IR, optical, UV, and X-ray data in order to characterize its long-termvariability from 2000 to 2022. At least one optical changing-look eventoccurred between 2011 and 2014, when the AGN changed from a Type 1.8/1.9Seyfert to a Type 1. It then faded considerably at all wavelengths, followed bya dramatic but slow increase in UV/optical brightness between 2021 and 2022.Near-IR (NIR) spectra in 2022 show prominent broad Paschen lines that areabsent in an archival spectrum from 2010, making NGC 5273 one of the few AGNsto be observed changing-look in the NIR. We propose that NGC 5273 underwentmultiple changing-look events between 2000 and 2022 -- starting as a Type1.8/1.9, NGC 5273 changes-look to a Type 1 temporarily in 2002 and again in2014, reverting back to a Type 1.8/1.9 by 2005 and 2017, respectively. In 2022,it is again a Type 1 Seyfert. We characterize the changing-look events andtheir connection to the dynamic accretion and radiative processes in NGC 5273,and propose that the variable luminosity (and thus, Eddington ratio) of thesource is changing how the broad line region (BLR) reprocesses the continuumemission.

Multiple Flares in the Changing-Look AGN NGC 5273