In recent years, astronomers have discovered thousands of planets and planetary systems orbiting nearby stars. Some are small and rocky, like the Earth, whilst others are gas giants, like Jupiter. It is now believed that most stars in the Universe have planets orbiting them and that some of them have physical characteristics that resemble those of the Earth. The sheer number of stars in the Universe, each potentially with orbiting planets, along with the ubiquity of chemical species which are the building blocks of life, suggests that extraterrestrial life may be likely.


As part of the IAU's mission to promote and safeguard the science of astronomy through international cooperation, the IAU is the authority responsible for assigning official names to celestial bodies. Now, while celebrating its first 100 years of fostering international collaboration (IAU100), the IAU wishes to contribute to the fraternity of all people with a significant token of global identity. Following the first NameExoWorlds competition, which named 19 "ExoWorlds" in 2015, the IAU will now, within the framework of the IAU100 NameExoWorlds project, offer every country the chance to name one planetary system, comprising an exoplanet and its host star. Each country’s designated star is visible from that country, and sufficiently bright to be observed through small telescopes.


We encourage all people of Earth to consider themselves “Citizens of the Cosmos”, and set aside borders, wars, and cultural differences for a universal, peaceful view of humanity as just one race, possibly among many cosmic neighbours in the Universe.