Photo Agency - Astronomy - Space - Nature

> Earth, Pluto, Charon, and Earth's Moon compared

Earth, Pluto, Charon, and Earth's Moon compared

author: Walter B. Myers/Novapix

reference: a-sys98-00300

Image Size 300 DPI: 27 * 18 cm

Pluto's diameter less than 20 percent that of the Earth's (smaller than the Earth's Moon). It has less than one percent the mass. If you weigh 180 pounds on Earth, you would weigh 11 pounds on Pluto. Pluto is 30 to 48 times further from the Sun than the Earth (Pluto's orbit is highly elliptical). Pluto's moon Chiron is over half the size of Pluto itself, leading astronomers to originally classify the Pluto-Charon system as a "double planet." They were also considered "binary planets" because the smaller Charon doesn't actually orbit around Pluto, rather Pluto and Charon orbit a common gravitational center (the "barycenter') located above Pluto's surface. In 2006 the International Astronomical Union (IAU) demoted Pluto from its status as the Solar System's 9th planet to a dwarf planet, and as the IAU has yet to formalize a definition for binary dwarf planets, Charon is currently regarded as a satellite of Pluto.

Keywords for this photo:

134340 PLUTO - ASTRONOMY - CHARON - COMPARISON - DWARF PLANET - EARTH - ILLUSTRATION - MOON - PLANET - PLUTO - SATELLITE - SIZE - SOLAR SYSTEM - TNO - TRANSNEPTUNIAN OBJECT -