NASA says faraway world Ultima Thule shaped like 'snowman'

Agence France-Presse

Posted at Jan 03 2019 05:35 AM

Ultima Thule, 20-mile-long (32-km-long) space rock, taken by NASA's New Horizons spacecraft, taken at 5:01 GMT on January 1, 2019, just 30 minutes before closest approach from a range of 18,000 miles (28,000 kilometers), is shown in this image released by Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, US, on January 2, 2019. Courtesy NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Handout via Reuters

WASHINGTON - Four billion miles from the sun floats Ultima Thule, an icy celestial body that NASA scientists announced Wednesday is aptly shaped like a giant snowman. 

The first detailed images beamed back from the US agency's New Horizons mission allowed scientists to confidently determine the body was formed when two spheres, or "lobes," slowly gravitated towards each other until they stuck together -- a major scientific discovery.

The New Horizons spacecraft on Tuesday flew past Ultima Thule, which was discovered via telescope in 2014 and is the farthest and potentially oldest cosmic body ever observed by a spacecraft.

Before that flyby, the only image scientists had was a blurry one showing Ultima Thule's oblong shape, resembling something like a bowling pin or a peanut.

"That image is so 2018... Meet Ultima Thule!" said lead investigator Alan Stern, doing little to hide his joy as he revealed a new sharper image of the cosmic body, taken at a distance as close as 17,000 miles (about 27,000 kilometers) with a resolution of 140 meters per pixel.

"That bowling pin is gone -- it's a snowman if anything at all," Stern said during a NASA briefing.

"What this spacecraft and this team accomplished is unprecedented."

Ultima Thule's surface reflects light about as much as "garden variety dirt," he said, as the sun's rays are 1,600 times fainter there than on Earth.

The body is roughly 19 miles long and completes its own rotation in about 15 hours. NASA dubbed the larger lobe Ultima, and the other, which is about 3 times smaller, Thule.

Carly Howett, another researcher of the mission, noted that "we can definitely say that Ultima Thule is red," perhaps due to irradiation of ice.