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Dual epoch spectroscopy of the lenticular galaxy, NGC 4203, obtained with theHubble Space Telescope (HST) has revealed that the double-peaked component ofthe broad H{\alpha} emission line profile is time variable, increasing by afactor of 2.2 in brightness between 1999 and 2010. Modeling the gasdistribution responsible for the double-peaked profiles indicates that a ringis a more appropriate description than a disk and most likely represents thecontrail of a red supergiant star that is being tidally disrupted at a distanceof ~ 1500 AU from the central black hole. There is also a bright core of broadH{\alpha} line emission that is not time variable and identified with a largescale inflow from an outer radius ~1 pc. If the gas number density is > 10^6cm^{-3}, as suggested by the absence of similarly broad [O I] and [O III]emission lines, then the steady state inflow rate is ~ 2 x 10^{-2}M{_{\sun}}/yr which exceeds the inflow requirement to explain the X-rayluminosity in terms of radiatively inefficient accretion by a factor of ~6. Thecentral AGN is unable to sustain ionization of the broad line region, thediscrepancy is particularly acute in 2010 when the broad H{\alpha} emissionline is dominated by the contrail of the in-falling supergiant star. However,ram pressure shock ionization produced by the interaction of the in-fallingsupergiant with the ambient interstellar medium may help alleviate the ionizingdeficit by generating a mechanical source of ionization supplementing thephotoionization provided by the AGN.

Time Variable Broad Line Emission in NGC 4203: Evidence for Stellar Contrails