As part of the 100thAnniversary celebrations of the International Astronomical Union (IAU) every country in the world is being given the chance to name their own star and an orbiting exoplanet. This is the IAU100 Name ExoWorlds project.

The star chosen for Australia to name is currently known by its catalogue number HD 38283. It is a 7thmagnitude yellow-white dwarf star in the constellation of Mensa, the Table Mountain. At that magnitude, this star is not visible to the unaided eye. Mensa contains part of the Large Magellanic Cloud (LMC) within its boundaries, which is the largest satellite galaxy to our own Milky Way, but HD 38283 is definitely within the Milky Way, lying only 125 light years away. By comparison the LMC is 180,000 light years distant.

Mensa is named after Table Mountain at the Cape of Good Hope on the southern tip of Africa. The misty star cloud of the LMC is reminiscent of the cloud that often sits atop the real mountain at the cape.

The exoplanet, currently designated HD 38283 b, is a gas giant type planet with 0.4 times the mass of Jupiter. It orbits the star at roughly the same distance as the Earth does the Sun (1.02 AU) and in 363.2 Earth days.

There are several rules to be considered in naming the star and exoplanet, and these can be accessed via the competition website. Since it is also the International Year of Indigenous Languages, speakers of Australian Indigenous languages are encouraged to submit names.

Website: name-exoplanet.net.au

Contact Information:

James Murray

exoplanets@mbo.org.au

m: 0409703929