91福利

The First Close-up Look at the Pluto System

NASA's New Horizons mission conducted the first flyby of the Pluto system on July 14th this year. Pluto was revealed to be a world of astonishing geological diversity, with ancient but heavily eroded cratered terrains and extensive young, crater-free, regions that may be undergoing active resurfacing. Solid nitrogen may be responsible for much of the recent activity, which includes glacial flow and disruption of the crust to generate mountains several kilometers high, but other landforms currently defy explanation. Pluto's atmosphere is hazy, very vertically extended, and continually leaking into space. Pluto's large moon Charon, probably created in a giant impact similar to that which created Earth's moon, also shows surprising geological complexity. Pluto's retinue of four small satellites are fascinating in their own right, due to their complex dynamical and rotational interactions. Following its success at Pluto, the New Horizons spacecraft continues its journey deeper into the Kuiper Belt, and, subject to continued funding, will make close-up observations of the small Kuiper Belt object 2014 MU69 on New Year's Day in 2019.