Washington, DC Jan 3: “Meet #UltimaThule! What you’re seeing is the 1st contact binary ever explored by a spacecraft. This object, which we can now see is a contact binary, used to be 2 separate objects that are now bound together.” Tweeted NASA. @NASANewHorizons.
NASA's New Horizons spacecraft flew past Ultima Thule in the early hours of New Year's Day, ushering in the era of exploration from the enigmatic Kuiper Belt, a region of primordial objects that hold keys to understanding the origins of the solar system.
At left is 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. Preliminary measurements of this Kuiper Belt object suggest it is approximately 20 miles long by 10 miles wide (32 kilometres by 16 kilometres). An artist's impression at right illustrates one possible appearance of Ultima Thule, based on the actual image at left. The direction of Ultima's spin axis is indicated by the arrows.
Ultima Thule's odd shape indicates that it formed as two spherical rocks slowly fused together in the early days of the solar system. Scientists call it a "contact binary", and it lends support to a theory that suggests worlds are born from slow accumulation, rather than catastrophic collisions.