An electronic vote has been conducted among all members of the International Astronomical Union, and the resolution to recommend renaming the Hubble law as the Hubble-Lemaître law has been accepted. The Hubble-Lemaître law describes the effect by which objects in an expanding universe move away from each other with a velocity proportionally related to their distance. This resolution was proposed in order to pay tribute to both Lemaître and Hubble for their fundamental contributions to the development of modern cosmology.

The discovery of the apparent recession of galaxies is a founding pillar of modern cosmology and a major milestone of astronomical research. To acknowledge the scientific contributions of Belgian astronomer Georges Lemaître to the scientific theory of the expansion of the universe, and by vote of its members, the International Astronomical Union (IAU) has decided to recommend the Hubble law to be renamed as the Hubble-Lemaître law.

Following a period of consultation with the astronomical community, the resolution to suggest renaming the Hubble law was presented and discussed at the XXX General Assembly of the IAU, held in Vienna (Austria) in August 2018. All Individual and Junior Members of the IAU (11072 individuals) were invited to participate in an electronic vote, which concluded at midnight UT on 26 October 2018. 4,060 cast a vote by the deadline (37%).

The proposed resolution has been accepted with 78% of the votes in favour and 20% against (and 2% abstaining).

One of the IAU’s roles is to foster exchanges of views and international discussions — and it strives to contribute to scientific discourses with historical facts. To honour the intellectual integrity and the supremely significant discovery by Georges Lemaître, the IAU is pleased to recommend that the expansion of the universe be referred to as the Hubble-Lemaître law.