Jupiter
CosMos Astronomy - Southern Hemisphere
". . . They which dream
An everlastingness in world's vast frame,
Think well some region where they dwell may wrack,
But that the whole nor time nor force can shake;
Yet, frantic, muse to see heaven's stately lights,
Like drunkards, wayless reel amidst their heights."
William Drummond, "The Shadow of the Judgment" (1630)
JUPITER DATA:
Distance from Sun:
Aphelion 816,520,800 km
Perihelion 740,573,600km
Equatorial Diameter:
143,000 km
Mass:
1.8986×1027 kg (317.8 Earths)
Composition:
89.8±2.0% Hydrogen
10.2±2.0% Helium
~0.3% Methane
~0.026% Ammonia
~0.003% Hydrogen deuteride
0.0006% Ethane
0.0004% water
Ices: Ammonia, water, ammonium hydrosulfide
Moons:
63
Orbital Period:
11.85920 yr
Rotational Period:
9hr 50.9min 55secs
Apparent magnitude:
-1.6 to to 2.94
Angular diameter:
29.8" to 50.1"
MAJOR MOONS (Diameter):
Io (3643km)
Europa (3122km)
Ganymede (5262km)
Callisto (4821km)
These moons, known as the Galilean Moons were discovered by Galileo in 1610. The majority of Jupiter's moons, excepting the Galilean moons, are irregular in nature and do not follow a regular orbit about Jupiter. Most if not all of these irregular moons were probably captured early on in the formation of the solar nebula.
Jupiter's immense gravitational pull affects anything passing close enough, for instance an asteroid, and either captures it for itself or flings it off on another path. Unfortunately, this may be towards the inner solar system and possibly Earth.
Details of rise and set as well as relevant monthly information can be found on the Sky This Month page.
Jupiter News
NASA's Juno Spacecraft Launches to Jupiter
NASA's solar-powered Juno spacecraft lifted off from Cape Canaveral Air Force Station in Florida at 9:25 a.m. PDT (12:25 p.m. EDT) Friday to begin a five-year journey to Jupiter.
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Juno to Show Jupiter's Magnetic Field in High-Def.
When it comes to magnetic fields, Jupiter is the ultimate muscle car. It's endowed with the biggest, brawniest magnetic field of any planet in the solar system, powered by a monster engine under the hood.
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More News... archived news on Jupiter, it's moons and current missions.
PAST SPACECRAFT MISSIONS
Galileo - The Galileo spacecraft's 14-year odyssey came to an end on Sunday, Sept. 21 2003, when the spacecraft passed into Jupiter's shadow then disintegrated in the planet's dense atmosphere.
16 Oct. 2009
Galileo's Jupiter Journey Began Two Decades Ago
NASA's Galileo spacecraft began what would become a 14-year odyssey of exploration 20 years ago this Sunday, Oct. 18. Galileo was humanity's first emissary to orbit a planet in the outer solar system - Jupiter.