42 SNe Ia
SH0ES · 42 Type Ia supernovae
Measured
Riess et al. (2022) SH0ES Cepheid calibrator sample of exactly 42 Type Ia supernovae used to measure the local Hubble constant.
Riess et al. 2022 report HST Cepheid observations in the hosts of 42 Type Ia supernovae used to calibrate H0. The sample is the complete set of suitable SNe Ia at z ≤ 0.01 over four decades. Baseline H0 = 73.04 ± 1.04 km s⁻¹ Mpc⁻¹. Hosts = 37; SNe = 42.
What it supports
Exact published calibrator count for the present Hubble-tension literature. The 42 is the primary sample size, not a press paraphrase.
What it does not
Not 42 Cepheid hosts (hosts are 37). Not a rounded H0 value. Not Flamsteed or catalogue padding. Not Adams.
ExactnessExact
Form42
Unitsupernovae
Strengthhard
When2022
Hung4 October 2026