A Picture of Jupiter's Moon

Io Facts

  • Moon Name: Io
  • Formed: Around 4.5 billion years ago
  • Discovered: January 7th 1610 by Galileo Galilei
  • Distance from Jupiter: Between 260,975 miles (perigee) and 263,088 miles (apogee)
  • Distance from the Sun: Around 484,000,000 miles
  • Time to Orbit Around Jupiter: Less than 2 Earth days
  • Total Surface Area: 26,041,666 square miles

13 Io Facts for Kids

  1. Io formed around 4.5 years ago.
  2. Io was discovered by Galileo Galilei on January 7th, 1610.
  3. Io is one of Jupiter’s seventy-nine known moons.
  4. Io has a radius of about 1,131 miles.
  5. The closest Io gets to Jupiter is 260,975 miles (perigee).
  6. The farthest Io gets from Jupiter is 263,088 miles (apogee).
  7. It takes Io less than two Earth days to orbit the planet Jupiter.
  8. The atmosphere and lack of water molecules on Io makes it extremely unlikely life as we know it could have evolved.
  9. Io is the densest moon in our solar system.
  10. Io is the most geologically active moon and object in our solar system, with over 400 active volcanoes.
  11. Io is the fourth largest moon in our solar system.
  12. Io is named after Io, a mythological priestess of Hera, who was one of Zeus’ lovers.

Additional Resources on Jupiter's moon Io