Pluto

Pluto is a dwarf planet located in the Kuiper Belt, a region of the solar system beyond the orbit of Neptune. It was discovered in 1930 by astronomer Clyde Tombaugh. Pluto was considered the ninth planet in our solar system until 2006 when the International Astronomical Union (IAU) reclassified it as a dwarf planet due to its size and its inability to clear its orbit of other debris.

Characteristics of Pluto

• Pluto is smaller than Earth's moon, with a diameter of about 1,473 miles (2,370 kilometers).
• It has a highly elliptical orbit that takes it closer to the sun than Neptune for a portion of its 248-year orbit.
• Pluto has five known moons, the largest of which is Charon.
• Its surface is composed of nitrogen, methane, and carbon monoxide ices, and it has a thin atmosphere primarily made up of nitrogen and methane.

Exploring Pluto

In 2015, NASA's New Horizons mission conducted a flyby of Pluto, providing the first close-up images and scientific data about the dwarf planet. The mission revealed details about Pluto's surface features, its atmosphere, and its moons, which expanded our understanding of this distant world.

Study Guide

1. What is Pluto's classification?
2. How does Pluto compare in size to Earth's moon?
3. What are the primary components of Pluto's surface?
4. Which mission provided the first close-up images and scientific data about Pluto?
5. How many moons does Pluto have, and what is the largest one called?