The Greeks coined the term planetes (“wanderers”) to describe the objects they saw in the sky that regularly moved against the background of the other, fixed stars. Over time this included many bodies that wander across the night sky, including the moon, Mercury, Venus, Mars, Jupiter, and Saturn, as well as smaller bodies like Sedna, Eris, Ceres, and Pluto. Defining exactly what constitutes a planet has caused lively debates among individual astronomers, professional observatories and universities that have pockmarked scientific history like the craters of the moon. The International Astronomical Union began in 1919 as a consortium of astronomers from all over the world with the mission of cooperative astronomical “research, communication, education and development.” As such the IAU has become the definitive organization for the uniform classification and naming of our continuing discoveries across space.
Since the first telescopes appeared around 1608 we have been able to observe much more than the easily visible stars that have always graced our skies and mythologies. Commonly known stars such as Polaris, Betelgeuse, Rigel and Vega were soon joined by many hundreds of others, which were often assigned designations, usually relative to the name of the discoverer and the chronology of the discovery. For example, German astronomer Wilhelm Gliese (pronounced GLEE-zə) published a 1957 catalog of 915 stars that were within 20 light years of Earth, essentially our closest stellar neighbors. Most of these continue to carry designations like Gliese 436, the 436th star listed in the catalog, not nearly as fun to say as ‘Betelgeuse.’ The IAU has developed periodic naming competitions for some of the more interesting and commonly studied of these many thousands of additional stars sans moniker. Astronomers, educators, students and laypeople alike contribute to these competitions, and the winning epithets from around the world are now represented in the heavens.
In 1992 the first exoplanet was confirmed. ‘Exo’ being the Greek for ‘outside,’ the IAU has defined an exoplanet as similar to a planet, a body that regularly orbits its host star, with enough gravitational pull to have cleared its orbit of smaller bodies, but existing outside of our own solar system. Finding these exoplanets is difficult, and only a handful have been directly imaged. Most are discovered through various indirect methods, including how their gravity tugs on a star as it orbits, making the host star “wobble,” or by measuring the dip in light observed when the exoplanet passes in front of its star as measured from our view. Since that first discovery in 1992 by researchers at Puerto Rico’s now defunct Arecibo Observatory, we have added more than 5,000 confirmed exoplanets to the list of rocky, liquid or gaseous bodies orbiting other stars. Commonly they follow the naming designation of the host star itself, such as the hot-Neptune icy body Gliese 436b, orbiting its red dwarf star approximately 32 light-years from us.
To learn more about these exoplanets astronomers have created ground-based observatories such as the Very Large Telescope in Chile’s Atacama desert, and space-based equipment like the James Webb Space Telescope orbiting with the Earth at four times the distance of the moon. The sensitivity of these telescopes, with their ability to observe outside the visible-light spectrum of optical telescopes, allows us to measure the volumes, masses and atmospheric compositions of some of these exoplanets. For example, Gliese 436b was chosen as one of the first exoplanets to be studied by the JWST, after the smaller Spitzer Space Telescope previously suggested a composition like that of a giant ice world, albeit with extremely high pressures and temperatures in excess of 800°F. The heat, pressure, and proximity to the radiation of its star at just 2.6 million miles suggested that a giant cloud of gas observed around the exoplanet was actually a comet-like tail stretching 9 million miles.
An exotic exoplanet, 21 times the mass of Earth, soaring around its star every 62 hours, with a surface of solid ice that exists at temperatures hotter than a household oven, and carrying the monotonous designation Gliese 436b. Something had to be done, and to this end the IAU introduced NameExoWorld2022, an international competition to propose names for the more fascinating exoplanets that the James Webb Space Telescope will be dedicating time to observing.
The theme for the NameExoWorlds2022 competition was indigenous languages, so I assembled a team including representatives from Prescott’s Museum of Indigenous People, Embry-Riddle Aeronautical University, The Northern Arizona Astronomical Consortium, and students from ERAU, Bradshaw Mountain High School, Northpoint Expeditionary Academy, and Liberty Traditional School. Together, we came up with submission for Gliese 436b and its host star Gliese 436, and have spent the last seven months promoting this through in-person outreach events around our region, articles, videos and podcasts available online, and most recently with the Ani Noquisi exhibit currently on display at the Museum of Indigenous People through December.
On June 7 the IAU announced that Gliese 436/b will now formally carry the approved names Noquisi and Awohali for the star and exoplanet, coming from the Cherokee language, meaning “star” and “eagle,” respectively. These names represent so much more than just two words picked at random from an indigenous language. They represent an oral history handed down for hundreds of generations telling of the connections between humanity, nature and the stars, as well as the first time that a star or exoplanet has officially carried a name in the indigenous language of a North American people.