Reid:  Over the last few months, the New Horizons probe has been gradually giving us greater insight into some strange worlds in the form of Pluto and its moons.  And now that we know what they look like, it's time to put some names on the maps.  

There are rules for this sort of thing, because names in space have a long history.  And the International Astronomical Union, the organization that's in charge of these things, has gotten tired of people naming asteroids after their pets.  So, the names that have been used by the mission scientists for these newly explored worlds won't technically be official until they're approved by the IAU.

But, in March and April, NASA asked people like you and me to suggest names for all the new features that would be discovered on Pluto and its moons.  And then, they were nice enough to ask us all to vote on the submissions.  The main rule was that names had to match certain themes, and for Pluto, those themes mainly have to do with underworld mythology.  It fits since Pluto was named, by an eleven year old girl, after the Roman version of Hades, god of the underworld.

But, other themes were permitted, too, including scientists, past space missions, and historic explorers.  There's actually a publicly available spreadsheet of 100+ names that made the final cut, which you can check out for yourself.  The link's in the description  That list explains how the dark whale-shaped area along Pluto's equator was given the name Cthulhu Regio, or region after H.P. Lovecraft's octopus, dragon man.  Apparently, it was the most popular name in the underworld beings category.  You can see it, and the other features, on this map created by the New Horizons team.  Basically, they took this image of Pluto and stretched it into a rectangle.  

The next most popular entry in the underworld beings category was Balrog, after the creatures from the Lord of the Rings.  So the Balrog Regio is the largest in the line of dark spots, nicknamed the Brass Knuckles.  The rest of the spots are named after mythological beings from real-life cultures, like the Maya.

Then there's the huge heart-shaped region on the face that was lit up during the fly-by,  The mission team decided to call it the Tombaugh Regio, after Clyde Tombaugh, the astronomer who discovered Pluto in 1930.  And there's plenty to explore within the Tombaugh Regio.

In the middle of the left side of the heart, there's an icy plain called the Sputnik Planum, after Sputnik, the first ever artificial satellite that was launched by the Soviet Union in 1957.  The two mountain range southwest of the Sputnik Planum are being called Norgay Montes and Hillary Montes, after Tenzing Norgay and Sir Edmund Hillary, the first known people to climb to the top of Mount Everest in 1953.

Finding themes for Charon, Pluto's largest moon, was a little more complicated.  The moon's discoverer, Jim Christy, originally named it after his wife, Charlene.  He turned the name into Charon because he thought it sounded more sciencey, but Charlene is the reason why some astronomers pronounce it *Sharon*.  Other astronomers wanted to name it after the Greek goddess Persephone, who was abducted by Pluto.  Luckily, for Christy, Charon also happened to be a character in mythology.  His job was to ferry souls across the River Styx in Hades.  

So, the IAU picked a theme for the features on Charon that had to do with travel, deciding that they should be named after fictional space explorers, their ships, and their destinations, as well as the authors and the artists who invented them.  That's why the big dark area at the top is called Mordor Macula, another Lord of the Rings reference.  This time to Mordor, the area of Middle Earth controlled by the evil Sarong, and Macula just means "distinct spot".

One of Charon's large plains is being called Vulcan Planum.  And speaking of Vulcans, lots of the craters on the moon have names that will be very familiar to Star Trek fans.  There's Spock Crater, Kirk Crater, Sulu Crater, Uhura Crater, you get the idea.  

But, don't worry, there are Star Wars themed craters too.  Like Vader, Leia Organa, and Skywalker craters.  If Dr. Who is more your speed, there's a Gallifrey Macula with a TARDIS Chasma that cuts right through it, and plenty of other fantastically nerdy references to choose from.

So, as you can see, there are rules for naming things, but people are still having plenty of fun with them.  There haven't been too many features named yet, but as New Horizons sends more images, those maps are definitely going to get a lot more detailed.  

So, if you ever find yourself on Pluto, or Charon, at least you won't get lost.

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