Depending on their orbital progress, Venus or Mars may be the closest planet to Earth at any given time. The distance between Venus and Earth varies between 24 and 162 million miles, and the distance between Earth and Mars varies between 34 and 250 million miles.
As the Apollo program was winding down in the 1970s, NASA came up with multiple proposals to use leftover Saturn hardware. One theoretical mission involved sending astronauts on a flyby of Venus, adapting a Saturn V upper stage similar to the later plans for Skylab. The mission would have taken advantage of the two planets' orbital proximity in 1973 to send a crew within 3,000 miles of the planet's surface for a brief examination.Learn More
Earth is unique in that scientists have found the planet to be the only one to have liquid water on its surface, intelligent life forms living on it, a moon that helps regulate surface temperatures, an atmosphere with 21 percent oxygen and plate tectonics, according to Space.com. Scientists believe Earth exists in a "Goldilocks zone" where conditions are just right to support life.Full Answer >
Venus is, by far, the closest match to the Earth in size. Venus has a measured diameter that is just about 95 percent that of the Earth and a planetary mass equal to 81.5 percent of the Earth's.Full Answer >
Orbitally, Uranus is the closest planet to Neptune. Its orbit is 1.62 billion miles away from Neptune's orbit. However, until Pluto was downgraded from planetary status in 2006, Pluto's orbit was the closest to Neptune's at only 1.42 billion miles away.Full Answer >
The closest planet to Uranus is Saturn, which is 898 million miles distant. Uranus is the seventh planet from the sun, while Saturn is the sixth planet. Uranus lies 1.78 billion miles away from the sun, while a distance of 886 million miles separates Saturn from the sun.Full Answer >