Ultima Thule vs Comet 67P/C-G
Date: 17 February 2019
Satellite: Rosetta
Copyright: Left: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Insti-tute; right: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
First impressions of the Kuiper Belt object Ultima Thule (left) revealed a surprisingly familiar appearance to the comet that ESA's Rosetta spacecraft explored for more than two years (right).
NASA's New Horizons flew by Ultima Thule on 1 January 2019, with subsequent images and data suggesting that its two lobes are rather more 'squashed' like a pancake, with respect to Comet 67P/Churyumov-Gerasimenko. Ultima Thule, which sits beyond the orbit of Neptune in the outskirts of the Solar System, is about 34 km long, with the two lobes measuring about 19.5 and 14.2 km across.
By comparison, Comet 67P/C-G's two lobes measure 4.1 × 3.3 × 1.8 km and 2.6 × 2.3 × 1.8 km. The comet likely originated from the Kuiper Belt and now orbits around the Sun on a 6.5 year journey that takes it from just beyond the orbit of Jupiter at its most distant, to between the orbits of Earth and Mars at its closest.
