NASA provides first images from Ultima Thule

Washington, Jan 2: NASA's New Horizons spacecraft has beamed back the first images of the distant worldlet Ultima Thule, after a historic flyby on the New Year's Day, revealing a bowling pin-shaped cosmic sentinel that possibly holds the key to understanding the origins of the solar system.

"Congratulations to NASA's New Horizons team, Johns Hopkins Applied Physics Laboratory and the Southwest Research Institute for making history yet again," said Jim Bridenstine, NASA Administrator.

Signals confirming the spacecraft is healthy and had filled its digital recorders with science data on Ultima Thule reached the mission operations centre at the Johns Hopkins Applied Physics Laboratory (APL) about 10 hours after New Horizons' closest approach to the object. NASA released a composite of two images taken by New Horizons' high-resolution Long-Range Reconnaissance Imager (LORRI), which provides the best indication of Ultima Thule's size and shape so far.

Images taken during the spacecraft's approach -- which brought New Horizons to within just 3,500 kilometres of Ultima -- revealed that the Kuiper Belt object may have a shape similar to a bowling pin, spinning end over end, with dimensions of approximately 32 by 16 kilometers. A

nother possibility is Ultima could be two objects orbiting each other, researchers said. Flyby data solved one of Ultima's mysteries, showing that the Kuiper Belt object is spinning like a propeller with the axis pointing approximately toward New Horizons. This explains why, in earlier images taken before Ultima was resolved, its brightness didn't appear to vary as it rotated. The team has still not determined the rotation period. As the science data began its initial return to Earth, mission team members and leadership revelled in the excitement of the first exploration of this distant region of space.

Ultima Thule, pronounced "Ultima Too-Lee," gets its nickname from a Latin phrase designating a place beyond the known world. A few basic facts about Ultima Thule, such as its size (about 20 miles wide) and its brightness (darker than Pluto), are known. But there's much more that's unknown, including its shape and its composition.

Astronomers didn't even know Ultima Thule existed when New Horizons was launched on its way to Pluto in 2006. The science team first spotted it in 2014, during a Hubble Space Telescope survey aimed at identifying objects to target after the Pluto flyby in 2015.

(with PTI inputs)