What is the closest planet in our solar system with an earth-like composition?
The closest planet to ours would be somehow Mars because NASA has found evidence of water. But that's not the correct answer.
In reality, there is no planet in our solar system that is close to ours. Saturn's moon Titan and Jupiter's moon Europa are the closest thing to Earth in the solar system. Titan has lakes of methane, it has a weather system (meaning it rains there) and more whereas Europa has a thick ice crust and astronomers suspect there maybe an entire ocean of water beneath it. Mars is the only obvious candidate for the closest PLANET to Earth, but there are more objects we have to yet discover.