International Astronomical Union (IAU)

The IAU was founded in 1919 to promote and safeguard the science of astronomy in all its aspects through international cooperation. Its individual members are professional astronomers from all over the world, at the Ph.D. level and beyond, who are active in professional research and education in astronomy.

The IAU General Assembly is held every three years, the next one will take place in August 2021.

If you are a professional, 'active' astronomer and your home or long-term residence is in the UK you are invited to apply for Individual or Junior membership of the IAU.

How to join

Professional scientists whose research is directly relevant to some branch of astronomy are eligible for election as Individual Members. The RAS, as the UK 'National Member' of the IAU , is responsible for vetting and forwarding nominations to the IAU. 

IAU applications open in the autumn, please contact the RAS Membership Officer for a link to the online application form. For more information about the qualification rules and application procedure please see the IAU website.

While it is not a condition that UK members of the IAU are Fellows of the RAS it is encouraged since the President of the Society is called upon to vote on behalf of all UK members.

IAU Members do not pay fees to the Union, these are covered by the RAS and Royal Society.