The IAU was founded in 1919 at a meeting held in Brussels, Belgium.

The IAU's mission is to promote and safeguard the science of astronomy, coordinate astronomical research, and establish standards for astronomical observations.

As of 2023, the IAU has 120 member countries.

The IAU has three official languages: English, French, and Spanish.

Ewine van Dishoeck is the current President of the IAU, having been elected in 2021.

Astronomy & Astrophysics is the IAU's flagship journal, publishing original research papers in all areas of astronomy.

The IAU is responsible for assigning names to stars and planets, approving the names of comets and asteroids, and maintaining a database of astronomical object names.

According to the IAU's definition, a planet is a celestial body that orbits the Sun, has a mass greater than that of Ceres, and has cleared its orbit of other objects.

The IAU is actively involved in promoting astronomy education by developing educational resources, organizing workshops and conferences, and supporting astronomy outreach programs.

The IAU is committed to promoting diversity and inclusion in astronomy by supporting programs that aim to increase the participation of underrepresented groups, advocating for policies that promote diversity and inclusion, and working to create a more welcoming and inclusive environment for astronomers.

The IAU plays a vital role in promoting international collaboration in astronomy by facilitating the exchange of astronomers between countries, supporting joint research projects, and organizing international conferences and workshops.

The IAU is actively involved in promoting public outreach in astronomy by organizing public lectures and events, supporting astronomy clubs and societies, and developing educational resources for the public.

The IAU plays a vital role in promoting the exploration of the solar system and beyond by supporting space missions, advocating for funding, and working with space agencies to coordinate exploration efforts.

The IAU is actively involved in promoting the search for extraterrestrial life by supporting research projects, advocating for funding, and working with other organizations to coordinate SETI efforts.

The IAU plays a vital role in promoting the development of new astronomical technologies by supporting research and development, advocating for funding, and working with industry to transfer new technologies to astronomy.