This is our best view yet of Ultima ThuleNASA/JHUAPL/SWRI

Some images are truly one in a million, and this latest effort from NASA’s New Horizons spacecraft is certainly no exception. It shows the object 2014 MU69, also known as Ultima Thule, in glorious detail as we’ve never seen it before.

New Horizons flew past Ultima Thule on New Year’s Day at a distance of 6.6 billion kilometres (4.1 billion miles) from the Sun, the most distant object we’ve ever visited in the Solar System. It orbits in a ring of asteroids and comets in the outer Solar System known as the Kuiper Belt.

Measuring about 30 kilometers (20 miles) across, we’re now starting to learn some fascinating details as data pours back about this Kuiper Belt Object (KBO), including getting a glimpse at its “snowman” shape. This is likely the result of two separate objects dating back to the dawn of the Solar System 4.5 billion years ago joining together, in a process called accretion.

We think this may have been the same process that formed the planets like Earth, with many different small objects like this sticking together over time, so studying Ultima Thule could very well tell us about our own origins.

New Horizons’ latest image of Ultima Thule is our highest resolution look at the object yet. It was taken by the spacecraft’s wide-angle Multicolor Visible Imaging Camera (MVIC) at a distance of 6,700 kilometers (4,200 miles) from the object. New Horizons snapped the image at 5.26am UTC on January 1, seven minutes before the spacecraft’s closest approach.

This enhanced view of Ultima Thule reveals some tantalizing new details of the object. For example, we can clearly see some large craters on its surface, including a particularly large divot on the smaller lobe measuring seven kilometers (four miles) across.

This large crater could be a sign of an ancient impactNASA/JHUAPL/SWRI

Towards the top of the larger lobe, we can also see a host of smaller craters measuring about 0.7 kilometers (0.4 miles) across. These are illuminated thanks to the angle of sunlight in this position at the day and night boundary, known as the terminator.

“Not clear is whether these pits are impact craters or features resulting from other processes, such as ‘collapse pits’ or the ancient venting of volatile materials,” the John Hopkins University Applied Physics Laboratory, who runs the mission, said in a statement.

Also of interest is the bright “collar” that seems to be separating the two lobes, which may reveal clues about how these two objects were joined together as a binary. And some scientists have noticed how the bright ring on the larger lobe resembles the larger crater on the smaller lobe, possibly suggested it rolled into place after an impact.

Smaller craters are visible at the terminator on the larger lobeNASA/JHUAPL/SWRI

New Horizons is continuing to send data back to Earth, so we can expect more fascinating images soon. It’ll take a long time for us to get all the data back though – the transfer rate is so slow that we won’t receive the last data until September 2020.

“This new image is starting to reveal differences in the geologic character of the two lobes of Ultima Thule, and is presenting us with new mysteries as well,” Principal Investigator Alan Stern from the Southwest Research Institute in Boulder, Colorado said in the statement. “Over the next month there will be better color and better resolution images that we hope will help unravel the many mysteries of Ultima Thule.”

This future data will include information on the composition and the temperature of the object. Scientists will also use the images to search for tiny moons or debris orbiting nearby, and also hunt for any signs of an atmosphere.

As for the New Horizons spacecraft, after flying past Ultima Thule it is now continuing its journey out of the Solar System. It will remain in the Kuiper Belt until 2028, with enough power to last until 2038. This means it may have an opportunity for a flyby of another object in the 2020s.

Until then, we’ve got plenty more exciting science to come from Ultima Thule. And thanks to this hardy spacecraft whizzing through space, we’re learning more about this region of the Solar System and our own beginnings than ever before.


… we have a small favour to ask. Hurn Publications is editorially independent, meaning we set our own agenda. Our journalism is free from commercial bias and not influenced by billionaire owners, politicians or shareholders. No one edits our editor. No one steers our opinion. This is important because it enables us to give a voice to the voiceless, challenge the powerful and hold them to account. It’s what makes us different to so many others in the media, at a time when factual, honest reporting is critical.

If everyone who reads our reporting and writing, who likes it, helps to support it, our future would be much more secure. We ask that you follow us and subscribe to our publication.