Pluto & Moons Daniel & Ebony

Moons All the planet have moons except for Mercury and Venus Triton, Neptune’s Moon The Galilean Moons Moons All the planet have moons except for Mercury and Venus It is one fourth the size of the Earth and has no atmosphere. The size in kilometers: 1,737.5 kilometers Our moon is thought to have formed when debris made contact with the still-forming Earth, and was blasted back into space, later pulled together to make the Moon. Mars has two moons called Phobos and Deimos Galileo Galilei discovered four of Jupiter’s moons, Io, Europa, Ganymede, and Callisto, in 1610. They are named the Galilean moons after him. Saturn’s moon Titan is the second largest moon and has its own significant atmosphere. Scientists are interested in Titan because it has a similar atmosphere to early Earth’s atmosphere Neptune’s Triton has an atmosphere as well, but it is much thinner than Titan. Triton orbits Neptune in the opposite direction, suggesting this moon did not form near the planet. It may have formed somewhere else and was later pulled in by Neptune’s gravitational pull.  

Pluto Pluto once was the ninth planet, but NASA later decided it was a dwarf planet when evidence was found about simular and larger bodies orbiting our outer system; which forced the science community to create criteria to define a planet. Pluto failed one out of the three criteria . Like a terrestrial planet, it is small; but, because it is comprised of rock and ice, its density is low. Orbit: 5,913,520,000 km (39.5 AU) from the Sun (average) Diameter: 2274 km Mass:1.27e22 kg Neighbour: Neptune and Kuiper belt Pluto is only 1,430 miles (2,302 kilometres) in diameter and is about 1/6th the size of Earth. Pluto is actually smaller than our own Moon!

Sources: http://nineplanets.org/pluto.html Solar system space school http://www.space.com/18135-how-big-is-the-moon.html