Venus and Earth are sometimes called sister planets because of their similar size, but don't let this comparison fool you! Venus, the second planet from the Sun, has a thick and heavy atmosphere that traps the Sun's heat to produce sizzling temperatures. This planetary greenhouse has been visited by over twenty spacecrafts. Each mission returned with important data about this mysterious planet.

Diameter: 7,500 miles Number of Moons: 0
Location: 2nd planet from Sun
Average Distance from Sun: 67 million miles
Average Surface Temperature: 870 degrees F
Orbital Period: 224.7 days
Characteristics: thick clouds filled with acid from its many volcanoes cover its surface
Significance: Earth's closest neighbor, just slightly smaller than Earth

Image credits: main image: courtesy of NASA; quote, © AMNH.