Length Of A Day And Year On Jupiter
It takes Jupiter 9.8 Earth hours to revolve around its axis (this is a Jovian day). It takes Jupiter 11.86 Earth years to orbit the sun once (this is a Jovian year).
Jupiter is made of gases and liquids, so as it rotates, its parts do not rotate at exactly the same velocity. It rotates very rapidly, and this spinning action gives Jupiter a large equatorial bulge; it looks like a slightly flattened sphere (it is oblate.).
Jupiter’s Orbit:
Jupiter is 5.2 times farther from than the Sun than the Earth. On average, it is 480,000,000 miles (778,330,000 km) from the sun. Jupiter is 749,900,000 Km from the Sun. Jupiter has no seasons. Seasons are caused by a tilted axis, and Jupiter’s axis is only tilted 3 degrees (not enough to cause seasons). Jupiter has four large moons and 13 small ones. Galileo spacecraft first discovered the four largest moon of Jupiter, called Io, Europa, Ganymede and Ganymede and Callisto. Ganymede is the largest moon in the Solar System
Atmosphere And Planetary Composition:
Temperature Range:
The cloud-tops average 120 K=153*C=-244*F.
Atmosphere:
Jupiter is a gaseous planet; it does not have a solid surface like the Earth does (but probably has a solid, rocky core 10 to 15 times the mass of the Earth). When we look at Jupiter, we are seeing icy clouds of gases moving at high speeds in the atmosphere. Jupiter’s atmosphere is composed of about 90% hydrogen and 10% helium. There are only minute traces (0.07%) of methane, water, ammonia and rock dust.
Mantle:
Pressurized hydrogen in the mantle may generate electric currents that generate Jupiter’s powerful magnetic field. The outer mantle is liquid hydrogen; the inner mantle is liquid metallic hydrogen. The layers of extraordinarily compressed hydrogen are in a state so extreme that it has never been produced in Earth. The pressure is so great that the hydrogen molecules inside Jupiter conduct heat and electricity very well, in a metal-like fashion (they do not do this under Earth-like condition). Inside Jupiter, electrons from hydrogen molecules move freely from molecule to molecule (like the electrons of a metal; that is what allows the electrical and heat conductivity.
Core:
At the centre of the planet is a molten rock, which is many times bigger and more massive than the entire Earth. It is 20,000*C, about three times hotter than the Earth’s core.
Internal Heat:
Jupiter is a heat source; it radiates 1.6 times as much energy as it receives from the sun.
Magnetic Field:
Jupiter has a very strong magnetic field. The magnetic field is probably generated as the planet spins its deep metallic-hydrogen layer with electrical currents.
Spacecraft Visits:
Jupiter was first visited by NASA’s Pioneer 10, which flew by Jupiter in 1973. Later fly-by visits included: Pioneer 11, Voyager 1, Voyager 2, Ulysses, and Galileo.