Pirx, Halla, Muchatna And More — 100 Alien Planets Get Official Names

Artist’s impression of the newly named exoplanet Isagel (right) that orbits the star Aniara (HD 102956) in the Big Dipper 399 light years from Earth. The planet is about as massive as Jupiter and orbits its host sun every 6.5 days at distance of just 7.5 million miles (12 million km). Livia Pietrow CC BY-SA 4.0

People of the world have spoken. 100 alien planets and their suns now have official names. After gathering suggestions from the public for the past six months, 100 new planets — from the currently-known list of 4,160 discoveries —  were officially named as part of the International Astronomical Union’s (IAU) NameExoWorlds Project.  The IAU, which has the authority to approve or create names for new discoveries whether it be exoplanets or Venusian volcanoes, chose the names based on suggestions submitted by regular folks from nearly every country on Earth.

What I especially like is that all the suns are visible in binoculars or a small telescope. The extraterrestrial planets are of course too faint to see, but to spy the stars they orbit and say their names out loud make them, well … more real. So far, all the new systems appear to be single stars with one known planet. And those planets are all likely to be “gas giant” similar to Jupiter in size with masses between about 10 percent and 500 percent of Jupiter’s mass. Most of the known exoplanets are giants because big ones are easier to spot in the data than little ones.

Artist impression of Mulchatna (right), the planet name submitted and accepted by the United States to the IAU. Located 255 light years away in Cassiopeia, the planet is similar in size to Jupiter (left). Aldaron / CC BY SA 3.0

Participants had to follow rules of course. Proposed names had to be of “things, people, or places of long-standing cultural, historical, or geographical significance, worthy of being assigned to a celestial object.” No offensive language, nothing commercial, no politics, pets or naming a planet after a living person. Indigenous names from myths or landscape features were very popular.

The IAU may conduct more campaigns like it in the future, so if your favorite moniker missed out this time around you’ll probably get another opportunity. In the meantime, here are a few examples you can hunt up the next clear night. I tried to pick some of the brightest, and all are visible in 50mm binoculars from a dark sky. If you live in the suburbs or city, you’ll need a small telescope. Except for Halla, a 6.8 magnitude star in the Little Dipper. That should be visible in binoculars even with light pollution.

Here’s the complete list. Peruse it sometime — you’ll enjoy reading the stories behind the names. Below you’ll find descriptions of several of the planets and maps to help you find them. If you need more detailed maps, paste the star’s name (in parentheses) into a free sky-charting program like Stellarium.

  1. Algeria — Tassili orbits the 8.3 magnitude yellow giant star Hoggar (HD 28678) in Taurus 740 light years from Earth. Tassili is a UNESCO World Heritage site renowned for its cave paintings and geological formations. Hoggar is a mountain range in southern Algeria.
  2. Argentina — Nosaxa orbits the 8.1 magnitude yellow-white star Naqaỹa (HD 48265) in Puppis some 293 light years away. Nosaxa means “spring” and Naqaỹa means brother in the native Moqoit language and leads us to call all humans brother.
  3. South Korea — Halla orbits the 6.8 magnitude yellow giant star Baekdu (8 Ursa Minoris) in the Little Dipper 522 light years away. Halla is the highest mountain in S. Korea and considered sacred. Baekdu is located in North Korea and the highest mountain on the Korean peninsula and symbolized the spirit of the Korean people.
  4. Sweden — Isagel orbits the 7.9 magnitude star orange giant star Aniara (HD 102956) in the Big Dipper 399 light years away.  Isagel is the name of the spaceship pilot in the science fiction poem Aniara written by Swedish author Harry Martinson. Aniara is the name of the spaceship.
  5. United States — Mulchatna orbits the 8.1 magnitude yellow dwarf star Nushagak (HD 17156) in Cassiopeia 255 light years from Earth. The Mulchatna River is a tributary of the Nushagak River in Alaska. Nushagak (River) is famous for its wild salmon that sustains local Indigenous communities.
The star Hoggar (magnitude 8.3) with its exoplanet Tassili are inside the white circle. Stellarium
Baekdu (magnitude 6.8) with Halla in the Little Dipper. There are two stars sit very close inside the white circle. Baekdu is to the upper left as indicated. Stellarium
Nosaxa with Naqaỹa in Puppis is located near the brilliant star Canopus, second brightest in the sky. Canopus is visible in the southern U.S. Stellarium
Aniara (magnitude 7.9) with Isagel in the Bowl of the Big Dipper. Stellarium
Nushagak (magnitude 8.1) with Mulchatna. Stellarium