Next Stop, Pluto

(2 of 2)

• Antenna • Heat shield • Thruster • Star tracking cameras • PEPSSI - Detects molecules escaping from Pluto's atmosphere • SWAP - Looks for magnetic fields and measures how fast the atmosphere is escaping • RTG - Powers the craft with a tiny amount of plutonium. Because the probe will travel so far from the sun, solar power was not an option • LORRI - A high-resolution telescope and camera capable of detecting features about the size of a football field • REX - Uses radio waves to analyze the atmosphere and determine night-side temperature • ALICE - Analyzes ultraviolet light to determine atmospheric composition • RALPH - Makes color maps of the surfaces of Pluto and Charon and uses infrared measurements to determine surface composition • SDC - Built by students in Colorado, this instrument will count and measure dust particles in space throughout the journey

MYSTERIES OF AN ICY WORLD • Pluto • Charon • If humans lived by Pluto time, they would never see a second birthday. The planet orbits the sun once every 248 Earth years • And if humans lived on Pluto, they wouldn't have to diet. Pluto's gravity is so weak that a man weighing 300 lbs. (136 kg) on Earth would weigh just 20 lbs. (9 kg) on Pluto • Unfortunately, breathing would be impossible. In addition to being intolerably cold, Pluto has a thin—and temporary—atmosphere of nitrogen molecules, with traces of carbon monoxide and methane. When the planet moves farther from the sun, the atmosphere freezes back onto the surface • Pluto is one of only two planets that rotate on their horizontal axis. Uranus is the other. A day on Pluto is equal to 6.4 days on Earth. • A radio signal moving at the speed of light takes about 4½ hours to reach Pluto from Earth