New Horizons was able to capture images of the distant (486958) 2014 MU69 object as it flew by.NASA / Johns Hopkins University Applied Physics Laboratory / Southwest Research Institute

Go beyond Earth and deeper into the solar system, past the craggy terrain of Mars and the shape-shifting storm of Jupiter, through the delicate rings of Saturn, beyond the silky clouds of Uranus and Neptune, and you will find a mysterious zone of small, icy objects. They number in the millions, some half the size of the continental United States, others as small as cities. They form a ring around the solar system, silent sentries guarding the blazing sun, which is so distant that it looks like any other star would.

Back in the day, about 4.6 billion years ago, the solar system was little more than a cloud of cosmic dust spinning around a newborn star. Gravitational forces pulled and smoothed some of the dust into spheres—the planets and moons. The small bodies here, in a region known as the Kuiper Belt, were left out in the cold, and have remained virtually unchanged all this time.

This year, NASA stopped by. The New Horizons spacecraft flew past one of these objects, snapping pictures and collecting scientific data as it went. No space mission had ever visited a target so far away, and NASA even held a New Year’s Eve party for scientists and engineers to count down to the historic pass around midnight.

The public had many questions for them. What does this thing look like? What’s so cool about it? And why does it share a name with a term used by Nazis?

Scientists had nicknamed the object Ultima Thule, a centuries-old phrase with roots in Latin literature. For most of its long history, Ultima Thule, or the word Thule alone, has been used to describe places beyond the limits of the known world, such as hard-to-reach Arctic lands.

But the name picked up more sinister associations in recent history. During the rise of Hitler, members of the Nazi Party in Germany imagined Ultima Thule as a land of Aryan purity. In the late 1990s, white-supremacist inmates in Portland, Oregon, produced a newspaper called Thule that printed racist and anti-Semitic articles. The Swedish rock band Ultima Thule, a group popular with right-wing listeners and once sponsored by a neo-Nazi movement, released its latest album in 2015.

The reporter Meghan Bartels first turned up some of these troubling associations in 2018, when NASA announced the nickname. But most people, including some of the New Horizons scientists and engineers themselves, didn’t know of them until Bartels’s story in Newsweek resurfaced around New Year’s Eve. The public reaction was swift and critical, and the message was explicit: Don’t give NASA missions names with Nazi ties.

Alan Stern, the lead scientist on the New Horizons mission, defended their use of the name.

“I think New Horizons is an example, one of the best examples, in our time of raw exploration, and the term Ultima Thule—which is very old, many centuries old, possibly over 1,000 years old—is a wonderful meme for exploration,” Stern said at a press conference after the flyby. “And that’s why we chose it. And I would say that just because some bad guys once liked the term, we’re not going to let them hijack it.”

Words are malleable in this way, and language once used to disparage and discriminate can be reclaimed and repurposed. Taking back a phrase with negative associations is a form of power, especially when the shift is led by people that a slur once targeted. And perhaps Stern would have a stronger case if the negative valence of Ultima Thule had faded over decades, and the “bad guys” were a thing of the past. But Nazis and white supremacists are not yet confined to history books; they can still be found today in 4chan message boards or street protests in Charlottesville, Virginia, and even in European parliaments.

In the scientific community, Ultima Thule is officially called (486958) 2014 MU69, a designation generated from standard naming practices for distant space objects. A small, icy object 4 billion miles from Earth, it is shaped like a snowman and flat as a pancake, with a rich texture and no atmosphere. After NASA selected it as a flyby target, the agency decided to give the object a spicier nickname and asked the public to send nominations online and vote. NASA does this pretty often, for all sorts of targets and missions.

“Nomenclature is an important way of communicating from scientists to the nonscientific public, and how we choose names, what we choose to name, is a sign of what we think is important or interesting or exciting,” says Keith Noll, a planetary astronomer at NASA.

Ultima Thule placed seventh. (Mjölnir, the hammer of the mythical god Thor, was first; I blame Thor: Ragnarok, which premiered a month before the poll opened in 2017, for this.) “I had never heard the term Ultima Thule before we had our naming campaign,” Mark Showalter, a planetary astronomer at the SETI Institute and the New Horizons scientist who led the process, told Newsweek last year.

Showalter uncovered the Nazi associations as he went through the list, Bartels reported. But he and other scientists liked the original meaning of Ultima Thule, and it seems that the term’s long, dreamlike history outweighed the more recent, troubling connotations. “‘Beyond the limits of the known world’—that’s such a beautiful metaphor for what we’re doing this year,” he said to Newsweek. (Showalter did not respond to requests for an interview.)

And so NASA ran with the name, promoting it on social media and merchandise. Journalists (myself included) adopted it, too; after all, Ultima Thule is far more approachable than something that reads like a SKU code. Meanwhile, many scientists, on the New Horizons team and elsewhere, referred to the object exclusively as MU69. They knew that someday, MU69 would get a real name, arbitrated and approved by an international organization responsible for naming objects in the universe, from little asteroids to big stars.

The New Horizons team is already thinking about it. “We haven’t proposed a formal name yet, but we will later this year,” Stern told me this week.

Stern can’t propose the name himself. According to the International Astronomical Union, the duty rests with the discoverer of an object. In the case of MU69, that would be Marc Buie, an astronomer at the Southwest Research Institute and a New Horizons member who has spent a decade studying the object. Brainstorming the name is a team effort, but Buie must be the one who submits their final pick. And thanks to the public backlash against Ultima Thule, the process may be more difficult than usual.

“I’ve got naming rights on like 400, 500 other Kuiper Belt objects, and I just haven’t gotten around to them yet,” Buie told me. “I just have to get around to it and say, ‘I like this name,’ and just send it in, and it’s done, and there’s no drama. But that’s because nobody cares one way or another what name I give it. But here you’ve got something that’s in the public eye, it’s getting a lot of clicks, a lot of eyeballs, and everybody treats that pretty seriously these days.”

The controversy taps into a long-standing problem in space exploration. Humankind’s ventures into the cosmos are steeped in the same language that characterized their journeys on Earth; astronauts and spacecraft are cast as pioneers brave enough to conquer wild frontiers and perhaps colonize new worlds. NASA has mostly moved away from such terminology, but it remains in use, including, to give one recent example, by the vice president, who described the United States as “a nation of restless pioneers ever striving to explore uncharted territories” in a speech this week.

“Even the word ‘exploration’—as opposed to investigation, study, etc.—alongside ‘pioneer,’ ‘mariner,’ ‘clipper’ in mission names, bears a specific, heavy history that most of the world population directly relates to European colonialism,” wrote Divya M. Persaud, a planetary scientist, in a comprehensive exploration of the complicated language of space science.

A name, in particular, is a powerful thing. “The act of naming determines its social life, how everyone else will know it,” says Valerie Olson, an anthropologist at the University of California at Irvine who studies science experts, political leaders, and others who shape different environments. “Only certain people have the power to designate space place names, and each object’s name connects it to some kind of history or place.”

Yes, outer space is distant and cold and mostly empty. But after centuries of study and exploration, it is brimming with artifacts of our culture, politics, and other traditions. It is naive to think that space science—that any science, really—exists in a realm untouched by terrestrial opinions.

“The really interesting thing to me is, something so far away can be given a name that makes people upset here on Earth,” says Alice Gorman, a space archaeologist who studies the heritage of human-made objects in space. “It’s a really clear message that this stuff is not just space science. These things have an impact. Naming things in the solar system and naming celestial bodies actually reflects a version of Earth back to us.”

Buie said the group has considered several names, but declined to say what they were. The rules of the International Astronomical Union vary by object. Moons of Jupiter, for example, must be named after mythological figures who were either descendants or lovers of Jupiter, the Roman equivalent of Zeus. (Yes, astronomers are still finding new moons around Jupiter.) For stars, the shorter the name, the better. Kuiper Belt objects like MU69 should derive their name from mythology.

Ultima Thule might fit this requirement, should the team decide to go all in. But it could snag on other rules. The organization stipulates that names should be “non-offensive,” a determination for the committee to make. Names associated with political activities can’t be proposed unless 100 years have passed.

“You could argue that, well, we want to reclaim the name now,” says Noll, who is a member of the International Astronomical Union committee that decides the names for small bodies. “But unfortunately, it’s being used currently by white-supremacist groups ... That, to me, constitutes current political activity.”

Plus, there’s already a celestial body named Thule, an asteroid discovered in the 1880s. “We don’t normally use the same name twice for two objects,” Noll says. “And putting ‘ultima’ in front of it is sort of like saying ‘super.’”

Some scientists wish the New Horizons team never came up with a nickname in the first place, and for reasons unrelated to Nazis. “My biggest concern is writing scientific papers about this object,” Buie said. “Twenty years from now, somebody wants to search to find old work on it, and if I’m not using the name known to history, then people aren’t going to be able to find my work.”

I asked him what would happen if he doesn’t like the name everyone else—including Stern and other parties whose opinion would carry significant weight, such as NASA headquarters—gets behind. Given the weight this name now carries, would he really have a choice? “It doesn’t seem like it, but I don’t know,” he said. “If they come up with something and I say, ‘I can’t stand this; don’t do it,’ are they going to listen to me? Until it happens, I can’t know.”

If the team suggests—and the committee approves—something other than Ultima Thule, NASA will have to unleash a fresh round of publicity for the object. And it might be difficult to wrench away the current label after spending so much time trying to get the public to care about it. “People are going to connect that title to the object just because it was used in the public arena, in the flyby, no matter what we rename it,” says Susan Benecchi, an astronomer at the Planetary Science Institute and a New Horizons member.

Naturally, the scientists I spoke with hope that the public pays more attention to the findings from the New Horizons mission. The first batch appeared in the journal Science this week and found, among other things, that MU69 has remained in pristine condition since the tumultuous formation of the solar system billions of years ago. The International Astronomical Union gives discoverers 10 years to submit name proposals, but Buie and others are anxious to get this one done sooner rather than later.

“It was just an amazing find and an amazing investigation that’s going to rewrite textbooks for years to come,” he said.

We’ll have to see what those textbooks call it.

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