NASA’s New Horizons spacecraft conducted a flyby of Ultima Thule on January 1st, and the images it took revealed the real shape and color of the mysterious object located 4 billion miles from the sun.
Ultima Thule, also known by its official designation 2014 MU69, looked like a fuzzy bowling pin in photos taken by New Horizons a week prior to the flyby. But the new imagery taken during the actual flyby showed that Ultima Thule is actually a “contact binary” of two roughly spherical lobes.
“That bowling pin [analogy] is gone,” New Horizons principal investigator Alan Stern, of the Southwest Research Institute (SETI) in Boulder, Colorado, said during a news conference on January 2nd. “It’s a snowman, if it’s anything at all.”
In addition to the object’s true shape, the new imagery also revealed that Ultima Thule has a reddish color. Mission team members said that Ultima Thule’s reddish hue is likely due to the discoloration of its icy surface material caused by deep-space radiation.
While some common people find New Horizon’s flyby of Ultima Thule uninteresting, it’s apparently a big deal for mission team members. “We think what we’re looking at it is perhaps the most primitive object that has yet been seen by any spacecraft, and may represent a class of objects which are the oldest and most primitive objects that can be seen anywhere in the present solar system,” said Jeff Moore of NASA’s Ames Research Center, the leader of New Horizons’ geology and geophysics team.
Stern also took the news conference as an opportunity to address the controversy surrounding the nickname the New Horizons team had chosen for Ultima Thule. Ultima Thule is a Latin phrase that means “a place beyond the known world,” but it was also adopted by Nazis to refer to the birthplace of the so-called Aryan race.
“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,” Stern explained. “Just because some bad guys once liked that term, we’re not going to let them hijack it.”
After all, the New Horizons team knew all along that Ultima Thule would only be a temporary nickname. The final and official name for the object shall be approved by the International Astronomical Union, which oversees all names in space. Mark Showalter, a planetary astronomer at the SETI Institute and investigator on the New Horizons mission who led the naming process, said in an interview last March that the permanent name for Ultima Thule is expected to be confirmed before the end of this year.