Jupiter (2)
Jupiter as seen from the Hubble telescope in 2014.
Diameter 142,984 km
88,846 mi.
Distance from the Sun 778 million km
483 million mi.
Astronomical Unit 5.2
Mass 1.8986×10^27 kg

317.8 Earths

Density 1.326 g/cm^3
Number of moons More than 64
Length of day 9 hours
Length of year 11 years
Atmosphere Components Hydrogen
Symbol Jupiter symbol

Jupiter is the fifth planet from the Sun and it is the is the largest planet in the solar system. It is approximately 143,000 kilometers (about 89,000 miles) wide at its equator. Jupiter is so large that all of the other planets in the solar system could fit inside it. More than 1,000 Earths would fit inside Jupiter.

Jupiter is like a star in composition. If Jupiter had been about 80 times more massive, it would have become a star rather than a planet.[1]

King of the GodsEdit

God of a king

A king.

Jupiter was the Roman god of the sky, although he was first recognized as a god of storms, thunder and lightning. As time went on, Jupiter became known as a protector of the roman people.

Jupiter was the Roman equivalent to the Greek supreme god, Zeus.


Great Red Spot

An image of Jupiter's Great Red Spot were taken by the Voyager spacecraft.

Jupiter is a giant gas planet. Its atmosphere is made up of mostly hydrogen gas and helium gas. The planet's surface is covered in thick red, brown, yellow and white clouds.[1]

One of Jupiter's most famous features is the Great Red Spot. It is a giant spinning storm, resembling a hurricane. At its widest point, the storm is about three-and-a-half times the diameter of Earth. Jupiter is a very windy planet. Winds range from 192 mph to more than 400 mph.

Jupiter rotates, or spins, faster than any other planet. One rotation equals one day. Jupiter's day is only about 10 hours long. Jupiter's orbit is elliptical, or oval-shaped. It takes 12 Earth years for Jupiter to make one revolution around the Sun, so a year on Jupiter is equal to 12 years on Earth.[1]

The temperature in the clouds of Jupiter is about minus 145°C (-234°F). The temperature near the planet's center is much, much hotter. The core temperature may be about 24,000°C (43,000°F).

If a person could stand on the clouds at the top of Jupiter's atmosphere, the force of gravity he or she would feel would be about 2.4 times the force of gravity on the surface of Earth. A person who weighs 100 pounds on Earth would weigh about 240 pounds on Jupiter.

Jupiter has an extremely powerful magnetic field, like a giant magnet. Deep under Jupiter's clouds is a huge ocean of liquid metallic hydrogen. As Jupiter spins, the swirling liquid metal ocean creates the strongest magnetic field in the solar system. At the tops of the clouds (tens of thousands of kilometers above where the field is created), Jupiter's magnetic field is 20 times stronger than the magnetic field on Earth.[1]

Moons of JupiterEdit

Jupiter System

Jupiter (top right); Europa (middle); Io (upper left); Ganymede (lower left); Callisto (lower right below the surface).

Jupiter has 69 moons.

  1. Metis
  2. Adrastea
  3. Amalthea
  4. Thebe
  5. Io
  6. Europa
  7. Ganymede
  8. Callisto
  9. Themisto
  10. Leda
  11. Himalia
  12. Lysithea
  13. Elara
  14. Dia
  15. Carpo
  16. S/2003 J 12
  17. Euporie
  18. S/2003 J 3
  19. S/2011 J 1
  20. S/2003 J 18
  21. S/2010 J 2
  22. Thelxinoe
  23. Euanthe
  24. Helike
  25. Orthosie
  26. S/2016 J 1
  27. Iocaste
  28. S/2003 J 16
  29. Praxidike
  30. Harpalyke
  31. Mneme
  32. Hermippe
  33. Thyone
  34. Ananke
  35. Herse
  36. Aitne
  37. Kale
  38. Taygete
  39. S/2003 J 19
  40. Chaldene
  41. S/2003 J 15
  42. S/2003 J 10
  43. S/2003 J 23
  44. Erinome
  45. Aoede
  46. Kallichore
  47. Kalyke
  48. Carme
  49. Callirrhoe
  50. Eurydome
  51. Pasithee
  52. S/2010 J 1
  53. Kore
  54. Cyllene
  55. S/2011 J 2
  56. Eukelade
  57. S/2017 J 1
  58. S/2003 J 4
  59. Pasiphae
  60. Hegemone
  61. Arche
  62. Isonoe
  63. S/2003 J 9
  64. S/2003 J 5
  65. Sinope
  66. Sponde
  67. Autonoe
  68. Megaclite
  69. S/2003 J 2

The largest of Jupiter's moons is Ganymede. It is the largest moon in the solar system. Ganymede is larger than the planet Mercury and three-fourths the size of Mars. Ganymede is the only moon in the solar system known to have its own magnetic field. Ganymede and Callisto have many craters and appear to be made of ice and rocky material.

Io has many active volcanoes. The volcanoes produce gases containing sulfur. The yellow-orange surface of Io is most likely made of sulfur from the volcanic eruptions. Europa is the smallest of the Galilean satellites. Europa's surface is mostly water ice. Beneath the ice may be an ocean of water or slushy ice. Europa is thought to have twice as much water as Earth.[1]