Newest Images of Ultima Thule Unveiled by Boulder-born New Horizons Mission

February 23, 2019
This photo, released by NASA on Friday, shows the Kuiper Belt object Ultima Thule, also known as 2014 MU69, as the New Horizons mission prepared to make its closest approach at 10:26 p.m. MST Dec. 31. Ultima Thule is believed to be the most primitive object ever encountered by a spacecraft.

The most dramatic images to date from the New Horizons flyby of the Kuiper Belt object Ultima Thule were released Friday, revealing numerous surface features not visible in earlier photographs, including several bright, circular patches of terrain.

Additionally, they depict several small dark pits near what is called the terminator, or, the border between the sunlit and dark sides of its body.

New Horizons was conceived in 1989 by a team of scientists led by Alan Stern, associate vice president of the space science and engineering division at Southwest Research Institute in Boulder.

After drawing global acclaim for its July 14, 2015, flyby of the dwarf planet Pluto , it continued hurtling outward through the Kuiper Belt, passing Ultima Thule — officially known as 2014 MU69 — at a distance of 2,200 miles.

In doing so, the mission achieved an exploration of the oldest and most distant object humans have ever visited, a pristine example of the building blocks that comprise the solar system, located one billion miles past Pluto.

The newest photos represent fulfillment of what mission scientists called their “stretch goal,” recording images just before the closest approach, pointing the spacecraft’s cameras so as to capture the sharpest possible pictures.

The new images were captured by the telephoto Long-Range Reconnaissance Imager just six-and-a-half minutes before New Horizons’ closest approach at 10:33 p.m. MST , with a resolution of about 110 feet per pixel.

The photos’ spatial resolution, and viewing angle, according to NASA, afforded an unprecedented opportunity for missions scientists to investigate Ultima Thule’s surface, its origin and evolution.

“Bullseye!” Stern, the mission’s principal investigator, exulted in a statement released through NASA. “Getting these images required us to know precisely where both tiny Ultima and New Horizons were — moment by moment — as they passed one another at over 32,000 mph in the dim light of the Kuiper Belt, a billion miles beyond Pluto. This was a much tougher observation than anything we had attempted in our 2015 Pluto flyby.”

Additionally, Stern said, “These ‘stretch goal’ observations were risky, because there was a real chance we’d only get part or even none of Ultima in the camera’s narrow field of view. But the science, operations and navigation teams nailed it, and the result is a field day for our science team. Some of the details we now see on Ultima Thule’s surface are unlike any object ever explored before.”

The scientific jury is still out, in terms of determining the cause of the numerous distinctive features on the bi-lobed body’s terrain.

“Whether these features are craters produced by impactors, sublimation pits, collapse pits, or something entirely different, is being debated in our science team,” said John Spencer, a deputy project scientist from SwRI.

According to mission operations manager Alice Bowman, at the Johns Hopkins University Applied Physics Lab, the spacecraft continues to operate flawlessly, nearly 4.13 billion miles from Earth.

At that distance, radio signals traveling at light speed reach the large antennas of NASA’s Deep Space Network six hours and nine minutes after New Horizons sends them, according to NASA.

The newest photos were released the same day as the ballet “New Horizons,” inspired by the groundbreaking NASA mission, was to make its debut in a presentation by the Boulder Ballet at the Gordan Gamm Theater at Boulder’s Dairy Arts Center.

Charlie Brennan: 303-473-1327, brennanc@dailycamera.com or twitter.com/chasbrennan