：从温柔触碰形成双星系统，到剧烈撞击造就月球，宇宙中的“吻”各有故事。 在太阳系里，地球和矮行星Pluto显得有些特别，它们是仅有的两个拥有超大卫星的世界。地球的月亮直径3476公里，约占地球宽度的四分之一，而Pluto虽只有2250公里宽，它的卫星Charon却足足有它一半大小。这种行星与卫星的比例之大，有时让人觉得它们更像是“双行星系统”，彼此绕着对方转，而不是小卫星围着大行星打转。可为什么只 ...

Charon also has an abnormally circular orbit of Pluto, with its orbital eccentricity (a value between 0 and 1, where 0 is a perfect circle and 1 is an open-ended parabola) only being about 0.000161.

An curved arrow pointing right. NASA's New Horizons spacecraft took us to Pluto for the first time in July 2015. Scientists are astonished by the incredible features they've observed on the dwarf ...

But on Charon, Pluto's nearest moon, they found this most familiar of geological features. There was more, on Pluto itself, that recalled the American mid-west. Dark streaks on Pluto's plains ...

He died 17 Jan 1997 and since then this day is called the Pluto Day. Pluto has five known moons: Charon, the largest, whose diameter is just over half that of Pluto; Styx; Nix; Kerberos ...

Pluto was always in a tough spot when it came to being a planet. Just 1,477 miles across, it's only one-fifth the diameter of Earth. It did have five known moons: Charon, Nix, Hydra, Kerberos and ...

This visual may only be used for the purpose of posting and/or reporting of this news release. Credit information must be provided as indicated.

I have been working with my research advisor, Leslie Young (Southwest Research Institute), on surface spectra of Pluto, Charon, and Triton. Upcoming and ongoing work includes reduction of Keck/OSIRIS ...

That’s because NASA wants New Horizons taking pictures of Pluto, its jumbo moon Charon and its four little moons during this critical time, not gabbing to Earth. NASA marked the moment live on ...