Research

New images of the distant Ultima Thule object have surprised scientists

New images of the distant Ultima Thule object have surprised scientists

One lobe looks kind of like an oddly shaped "walnut", the agency said, while the other side looks like more a "pancake". The image to the left is an "average" of ten images taken by the Long Range Reconnaissance Imager; the crescent is blurred in the raw frames because a relatively long exposure time was used during this rapid scan to boost the camera's signal level.

When NASA's New Horizons spacecraft zoomed by the twin space rocks known collectively as Ultima Thule earlier this year, the images it sent back seemed to show a "space snowman" in all its glory.

The newly released images brought crucial data to the scientists who strung 14 of these images into a short departure movie.

"While the very nature of a fast flyby in some ways limits how well we can determine the true shape of Ultima Thule, the new results clearly show that Ultima and Thule are much flatter than originally believed, and much flatter than expected", said Hal Weaver, New Horizons project scientist from the Johns Hopkins Applied Physics Laboratory.

New Horizons may have moved on from Ultima Thule, but it still has plenty of images stored in its robotic brain. "We've never seen something like this orbiting the Sun", he added. They were also taken from a different angle than the previous approach photos, revealing the crucial information of Ultima Thule's actual shape.

Scientists estimate Ultima Thule is about 19 miles long; its dual sections measuring 12 miles across ("Ultima") and nine miles across ("Thule").

More news: Miami police release video showing woman possibly being abducted

What initially looked like an upside-down two-ball anthropomorphic snow sculpture floating in space is actually a "contact binary": two stars whose components are so close they touch or merge. New data sent back to Earth has meant they'll need to rework our understanding about the shape of 2014 MU69 (aka Ultima Thule).

"This really is an incredible image sequence, taken by a spacecraft exploring a small world 4bn miles away from Earth", said the mission's principal investigator, Alan Stern.

'Nothing quite like this has ever been captured in imagery'. The images reveal an outline of the "hidden" portion of the Ultima Thule that was not illuminated by the Sun as the spacecraft zipped by, but can be "traced out" because it blocked the view to background stars also in the image. The central frame of this sequence was taken on January 1 at 05:42:42 UT (12:42 a.m. EST), when New Horizons was 5,494 miles (8,862 kilometers) beyond Ultima Thule, some 4.1 billion miles (6.6 billion kilometers) from Earth.

New Horizons is already 32 million miles (52 million kilometers) beyond Ultima Thule. Ultima Thule's shape is definitely unique so far in the solar system and its origins could, in turn, refine or change theories about the origin of the solar system itself.

As New Horizons beams more images through the solar system, we'll nearly certainly continue seeing weird, unprecedented stuff.

The primitive world was "born" this way, and did not evolve or deform through external processes to take on the odd shape, the team explains.