# How long is a day/year on Mars?

The farther a planet is from the sun, the longer it takes to make a full orbit (1 year). But each planet also rotates on its axis at different speeds, resulting in a shorter or longer day length. The two speeds are not necessarily related.

The earth rotates once every 24 hours, which is one day. But on Mercury, a day lasts almost 59 Earth days. And a year on Mercury lasts only 88 days. So if you were 8 years old on Earth, you would be 33 years old on Mercury.

**Venus** rotates much more slowly than earth, but travels around the sun faster. A day on Venus takes 243 Earth days. A year on Venus only takes 224.7 Earth days. If you were 8 years old on Earth you would be 13 years old on Venus.

**Mars** rotates on its axis about the same speed as Earth – each day on Mars takes 1.03 Earth days (24.6 hours). But a year on Mars takes much longer – 687 Earth days. If you were 8 years old on Earth you would be only 4 years old on Mars.

Each day on **Jupiter** takes only 9.8 Earth hours. But it takes 11.86 Earth years for Jupiter to orbit the sun once. If you were 8 years old on Earth you would be barely 8 months old on Jupiter.

One day on **Saturn** only takes 10.2 Earth hours since it spins more than twice as fast as earth. It takes 29.46 Earth years for Saturn to orbit the sun once. If you were 8 years old on Earth you would be barely 3 months old on Saturn.

Each day on **Uranus** takes 17.9 Earth hours. It takes 84.07 Earth years for Uranus to orbit the sun once. If you were 8 years old on Earth you would be barely 1 month old on Saturn.

Each day on **Neptune** takes 19.1 Earth hours. It takes almost 165 Earth years for Neptune to orbit the sun once. If you were 8 years old on Earth you would be barely 2 weeks old on Saturn. (Or, if you were one year old on Saturn you would be 165 years old on Earth.)

Pluto spins slowly. Each day on **Pluto** takes 6.39 Earth days. It takes 247.7 Earth years for Pluto to orbit the Sun once. If you were 8 years old on Earth you would be 12 days old on Pluto. (Or, if you were one year old on Pluto you would be 248 years old on Earth.)