The tension between measurements of the Hubble constant (H0) as determined from the "local" and "distant" Universe persists. The Carnegie-Chicago Hubble Program was designed to provide a calibration of the Type Ia Supernovae (SNe Ia) completely independent of the Leavitt Law for Cepheid variables. Our use of distances determined via the tip of the red giant branch (TRGB) provides a critical cross-check of systematics incurred in Cepheid-based distances, which include internal extinction local to the Cepheid, metallicity, and the underlying zero-point calibration of the Leavitt Law. In my previous talk, I argued that this calibration path for the SNe Ia is better aligned with the goal of producing a high-precision measurement of H0, due to its relative simplicity and ability to target galaxies of all Hubble types (Beaton et al. 2016). However, the method still faced significant challenges related to homogenizing its application and proving its precision. In this talk, I will present an update on our progress, which includes distance measures to an additional five SN Ia host galaxies (Hatt et al. 2018a, Hatt et al. 2018b) and several detailed explorations of the "best" application of the TRGB technique (Beaton et al. 2018, Beaton et al. in prep). But how do these new distances impact the calibration of the SNe Ia? While we can compare the distances to each host galaxy directly, the underlying question of if these distance scales agree is more nuanced than comparing two measurements. To understand this, we need to turn our attention to the Local Group where multiple techniques can be applied by multiple groups to the same galaxy. Using the nearby dwarf galaxy IC1613 (Hatt et al. 2017, Beaton et al. 2018), I will demonstrate that even in our own backyard the question of "what is the distance" is not easy to answer and that this provides some insight for how to understand the growing body of reanalyses of the SNe Ia based measurements of H0.

Salads, sandwiches, and wraps are catered by D'Angelo Italian Market.
Bottled water will be provided.

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