New Horizons’ last flyby: Ultima Thule

Steph P. Bianchini December 30, 2018 0 Comments

New Horizons is almost there. After the historical flyby of Pluto in 2015, the probe has continued its course across the Kuiper Belt and it is now readying up for this (historical all the same) encounter, expected in two day time, on January 1, 2019.

Scientist do not know what to expect. Ultima Thule, little more than a dim point of light to even the Hubble Space Telescope, is known as a “cold classical” Kuiper Belt body, meaning it has a nearly circular orbit only slightly inclined to the plane of the planets. It is an untouched relic left over from the birth of the solar system 4.6 billion years ago. Based on occultation observations from Earth, Ultima Thule appears to be an elongated body about 30 kilometres (19 miles) across, possibly a dual-lobed contact binary or two physically separated but gravitationally bound bodies. (Read the whole analysis here)

“We’re going to find out how this thing is built, how much it’s evolved, what it’s made of, if it has an atmosphere, if it has moons, if it has rings, we’re going to take its temperature, we’re going to measure its radar reflectivity, we’re going to find out if it’s surrounded by a dust cloud left over from formation,” Alan Stern, the mission’s principal investigator, declared.

New Horizons will flyby Ultima Thule, officially known as 2014 MU69 passing within about 3,500 kilometres (2,200 miles) of its as-yet-unseen surface at a velocity of 51,000 kilometres per hour, sending its scientific data four hours later. The first available image will be released on January 2, and everybody can’t wait to see this frozen’s world face.