What does a small, icy world roughly four billion miles from Earth have to do with the Nazis?
That’s the question NASA was wrestling with before it announced on Tuesday that a space object formerly known by the nickname Ultima Thule would now officially be named Arrokoth, a Native American word meaning “sky.”
The previous name was a Latin term that metaphorically means “a place beyond the known world.” When it was unveiled last year, NASA said the name was only temporary, but it still attracted criticism because the term has a historical association with the Third Reich.
But let’s start from the beginning.
What is Ultima Thule?
Until Tuesday, Ultima Thule was the informal name NASA used for a small, snowman-shaped object in the Kuiper belt, a desolate region of deep space that the agency said in a statement is home to “thousands of known small icy worlds.”
But that name was not registered with the International Astronomical Union and Minor Planet Center, which has international authority for the naming of objects in the Kuiper belt. Its official name was the impersonal-sounding “Kuiper belt object 2014 MU69.”
The object’s strangely shaped, rust-colored body is composed of two connected spherical lobes and measures just 21 miles across at its widest point. When it was photographed on New Year’s Day 2019 by NASA’s New Horizons spacecraft, it was the first object of its kind that planetary scientists had ever gotten to see up close.
The term Ultima Thule, however, has its origins much closer to home. It is a Latin term used in classical antiquity to denote distant and unknown lands, in particular ones that were cold, like the Nordic countries. That Northern European connection drew the attention of the Nazis.
“Thule was one of the names they gave to what they believed was the ancient Aryan homeland, a prehistoric Aryan utopia that collapsed because of racial miscegenation or a flood or what have you,” said Eric Kurlander, a professor of history at Stetson University in DeLand, Fla.
The name is also used by the Thule Society, a racist, occult group formed in 1918. The society gave birth the next year to the German Workers’ Party, which Adolf Hitler soon joined and used as the precursor to the Nazi Party.
“This isn’t just some obscure element among hundreds of others in the Nazi cosmology,” Dr. Kurlander said. “They named a tank division after Thule in World War II. It keeps popping up, which is why it probably makes sense not to name something that anyone has any interest in Thule. It has too much baggage as this point.”
How did that name end up on a space rock?
The connection between the object’s informal name and Nazi history was first reported by Newsweek. Mark Showalter, a scientist involved in the naming process, told the magazine in an interview that the name was suggested by roughly 40 people online.
The New Horizons team learned about the term’s Nazi connotation during the naming process but decided to move ahead with it anyway, he said. Mr. Showalter did not respond to a message seeking comment on Tuesday.
“The question we looked at very closely was whether this was a primary association,” Mr. Showalter told the magazine. “The primary association of Thule and Ultima Thule are with travel and exotic places and cold places — it’s associated with travel gear, it’s associated often with distant places in Greenland.”
S. Alan Stern, the principal investigator for the New Horizons mission, which also did a flyby of Pluto in 2015, addressed the controversy earlier this year when scientists released the photographs taken by the spacecraft.
“The term, Ultima Thule, which is very old, many centuries old, possibly a thousand years old, is a wonderful meme for exploration, and that’s why we chose it,” Dr. Stern told reporters at the time. “Just because some bad guys once liked that term, we’re not going to let them hijack it.”
Why was the space object renamed?
The idea of the unknown is built into the name Ultima Thule, so it was always intended to be temporary. Now that scientists have become acquainted with the little world, they wanted to give it a name that celebrated its distance from the Earth, as well as the sheer feat of having gotten close enough to study it, they said.
The new name was proposed to the International Astronomical Union and Minor Planet Center and announced on Tuesday at a ceremony at NASA headquarters in Washington.
In an emailed statement, Lori Glaze, the director of the planetary science division at NASA headquarters, said the name was chosen to honor the heritage of the Chesapeake Bay region, where the New Horizons mission was based. She declined to comment on the controversy around the name Ultima Thule.
“The (old) temporary and permanent names are not connected — the team chose the Algonquian/Powhatan word for ‘sky’ — Arrokoth — as a tribute to the indigenous peoples of the Chesapeake region,” Dr. Glaze said. “In particular, the New Horizons mission and Hubble Space Telescope are operated out of Maryland and the Chesapeake region and were critical to finding and studying the farthest object ever encountered by spacecraft.”