First close-ups of Ultima Thule reveal it resembles snowman

Saturday, 05 Jan, 2019

New Horizons Principal Investigator, Alan Stern said, "Let me say that bowling pin is gone". The larger sphere, which is an estimated 12 miles across, has been named "Ultima".

In the coming weeks and months, data from the New Horizons' flyby will continue to be received by the mission controllers. Two black-and-white pictures were released, with a resolution as fine as 140 meters (460 feet) per pixel.

"That image is so 2018".

The colour variation shows just how dark the object is with the brightest areas reflecting just 13 per cent of the light falling on them.

"It's only really size of something like Washington, D.C., and it's about as reflective as garden-variety dirt", he said.

"We were basically chasing it down in the dark at 32,000 miles per hour".

Images were taken by onboard instruments as the spacecraft zoomed past the world some 2,200 miles from its surface on New Year's Day, just past midnight.

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.

SwRI's Cathy Olkin, one of the mission's deputy project scientists, said the red color could well be due to organic chemicals known as tholins that are coating the surface. Scientists say no impact craters could be seen in the latest photos.

It's called Ultima Thule and it lies about a billion miles beyond Pluto. The Team hopes to set a course for new objects in the near future. The smaller, 9-mile-wide mass was given the nickname "Thule". Mutual gravitational attraction keeps them married despite their gentle, 15-hour rotation.

"This is the first object we can clearly tell was born this way, and didn't evolve to look this way", Stern said.

The two likely joined as early as 99 percent of the way back to the formation of the Solar System, colliding no faster than two cars in a fender-bender.

Future images sent back to earth will be of a higher quality as they will have been taken closer to the object and will benefit from better sunlight. "The data we have look fantastic and we're already learning about Ultima from up close".

Three views of Ultima Thule.

The object is so old and pristine that it's essentially like going back in time to the beginning of our solar system. It astounded the New Horizons science team, including astrophysicist Brian May.

"New Horizons swept down over Ultima Thule in a technical success beyond anything ever attempted before in space flight", said Stern in a livestream of the press conference on NASA's New Horizons site, and the shot of an elated (which is still an understatement) New Horizons team he put up onscreen spoke for itself.

"The spacecraft is in peak health", said Stern. "That's why we chose it".

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