Calibrating Type Ia Supernova Luminosities with Surface Brightness Fluctuations: The Old Pop to H0

A key rung of the distance ladder relies on the calibration of Cepheid variables. These young stars are found exclusively in star-forming spiral galaxies that could generate systematics through non-standard dust and metallicity variations. An alternative path to the local Hubble constant is to calibrate Type Ia supernovae with elliptical galaxies using the Surface Brightness Fluctuation (SBF) method. Per galaxy, infrared measurements of SBF distances have a precision comparable with Cepheids, but at a significantly lower cost in space telescope resources. The characteristics of type Ia supernovae in Cepheid calibrated hosts are substantially different from supernovae found in host galaxies calibrated with SBF.