The paper published in Science contains information on the development, geology and composition of the planetetimals. As NASA said, Ultima Thule has two rags that make it look like a snowman, even though it's actually flattened like a pancake. These two lobes seem to have formed close to each other, before they became a circulating pair that finally fused. The larger lobe measures approximately 22 x 20 x 7 km, while the smaller lobe measures approximately 1
In addition, Ultima Thule is colored very red. It is much redder than even Pluto, and indeed the reddest object New Horizons has visited. The team is not yet 100% sure, but believes that the redness is due to the modification of the organic materials on its surface. The paper also notes that the object rotates about its axis every 15.92 hours and that the brightest areas are in its neck where the flaps are connected. It also has two bright spots in its largest crater-like trait.
In terms of craters, Ultima Thule does not have many small ones, indicating that there are not many objects smaller than one kilometer in diameter in the Kuiper Belt. The newspaper also said that New Horizons has found no evidence of satellites, rings or an atmosphere around the object. These are just the first data from the flyby – we will learn more about the Flat Space Snowman in the coming months. The New Horizons probe still transmits data from the event and will do so by summer 2020.