Pluto’s moon, Charon. Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

The Kuiper Belt is a donut-shaped region of icy bodies beyond the orbit of Neptune. Until the 2015 flyby of the dwarf planet Pluto and its largest satellite Charon by the New Horizons spacecraft, little was known about these Kuiper Belt objects (KBOs). Using high-resolution images obtained from that flyby, a new study shows that Charon has a dearth of small craters (≲13 kilometers in diameter), which cannot be explained solely by geological resurfacing. This dearth means that there must be relatively few small objects (≲1 to 2 kilometers in diameter) in the Kuiper Belt. This surprising lack of small KBOs changes our view of the Kuiper Belt, and this research provides new insights into how the solar system originated. READ MORE »