The Hubble–Lemaître Law

Hubble assembled galaxy distances and recession velocities into a 1929 empirical relationship: greater distance corresponded, on average, to greater recession speed. Humason and others supplied essential spectroscopic data.

Lemaître had derived and published the expanding-universe relation in 1927. In 2018, the International Astronomical Union recommended the name Hubble–Lemaître law to acknowledge both theoretical and observational contributions.