And Ultima and Thule, according to New Horizons’ principal investigator Alan Stern at today’s NASA press briefing, the informal names the team have given the two lobes of the red object out in the Kuiper Belt New Horizons spent New Year’s encountering. The contact binary connected by a neck of material indicates two objects that came together and stuck sometime in the distant past when these kinds of interactions were leading elsewhere in the solar system to accretions that would eventually form the planets and their moons.

01 January 2019 image of Ultima Thule by New Horizons spacecraft and sketch of object and rotation courtesy James Tuttle Keane

During a morning press briefing aired on NASA TV on New Year’s Day 2019, New Horizons mission team leaders revealed the latest best image of Ultima Thule. Still a blur, the Kuiper Belt body’s shape is more apparent in this latest image. Still unclear: are the two lobes connected or are they in fact two separate objects orbiting each other? The pole of the object was pointed toward the spacecraft, meaning Ultima Thule rotates from that perspective like a propellor. Artist and planetary scientist James Tuttle Keane has helped visualize this geometry in his illustration included next to the image.

Consider what those of us can see in the night sky with healthy eyes, without any tools, far from city lights. Away from the dazzle of Sun’s day the Moon at night is, of course, the brightest above all. The visible stars make an obvious and fixed, so it seems, pattern that fills the celestial hemisphere. […]

This is it! Pluto is the last of the classical nine planets to be visited by a spacecraft from Earth. The New Horizons spacecraft will take close-up images and capture other useful data as it speeds by Pluto and its moons on July 14, 2015. This will complete the imaging grand tour of our solar system […]

The Rosetta spacecraft has returned the first images from its flyby of the asteroid 21 Lutetia. The image on the right was taken while the spacecraft was approximately 80,000 kilometers away and it shows a lumpy, cratered world. Lutetia is approximately 100 km in diameter. It is the largest asteroid yet visited by a spacecraft. […]