The January flyby of Arrokoth gave New Horizons a close look at a small, distant object that had once gone by the informal name Ultima Thule. By November 18, 2019, the NASA feature was drawing attention to what the encounter showed: a remote body with two distinct lobes, not a familiar inner-Solar-System asteroid. [shared-6a0532de01ebfee628ed79904a2a65a102b49609aa429174615653b42710ed8b]
A black-and-white sequence assembled from images taken at different viewing angles makes the paired shape easier to see. The larger lobe also appears notably flattened, though the source describes that as a hint rather than a settled measurement. Researchers said Arrokoth was likely made of two planetesimals joined together—the small building blocks from which planets formed billions of years ago. [shared-6a0532de01ebfee628ed79904a2a65a102b49609aa429174615653b42710ed8b]
The encounter came three and a half years after New Horizons passed Pluto. The spacecraft was still heading away from the Sun, adding roughly three Earth–Sun distances to its travel each year. That continuing drift is a measure of mission reach, not evidence that the flyby resolved every question about Arrokoth’s shape or formation. The open issue is how much more detail future analysis can establish from the brief passage and its changing views. [shared-6a0532de01ebfee628ed79904a2a65a102b49609aa429174615653b42710ed8b]