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  Moon phases for year 2010 by date and time and daily lunar calendar.

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  Lunar diets and dietary regimen for weight loss and body cleansing.

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  Moon in zodiacal signs and the zodiac under the lunar influence.

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  Solar activity today and real time space weather data.

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  Sky above us now and exact location of the planets and the constellations.

Moons of the planet Jupiter

The image presents the positions and the situation of the orbits of the Galilean moons around Jupiter and their current visibility (North is up, West is right). The image updates automatically on page reload.

Jupiter has 63 known moons. The first described are the Galilean moons discovered by Galileo Galilei in 1610. The moons Europa, Ganymede and Callisto are ocean-type, and Io is volcanic type.

The orbits of Io, Europa and Ganymede are in a Laplace resonance - for every four orbits of Io, Europa makes two, and Ganymede makes exactly one. This effect stretches their orbits in the form of ellipses.

From another side the strong tidal forces of Jupiter, try to make the orbits of its satellites nearer circular. When the moons are closer to Jupiter, the gravity of the giant planet deforms its satellites shape in ellipsoid, allowing them to recover their normal spherical shape only when they are away enough. These cycles heat the satellites inside, much on Io and less on Europe. Io is the celestial body with the most powerful volcanic activity in our Solar System, except the Sun.

Io

Io is the innermost of the four Galilean moons of Jupiter and one of the largest moons in the solar system. Diameter of 3643 km, mass 8.93 × 10²², average orbital radius of 421 800 km and orbital period of 1.77 days.

Europa

Europa is the fourth largest moon of Jupiter and the smallest of the four Galilean moons. Diameter of 3122 km, mass 4.8 × 10²², an average orbital radius of 671 100 km and orbital period of 3.55 days.

Ganymede

Ganymede is the largest moon in the solar system, with a radius greater than that of Mercury and Pluto (but with twice as less mass). Diameter of 5262 km, mass 1.48 × 10²³, an average orbital radius of 1 070 400 km and orbital period of 7.16 days.

Callisto

Callisto is the second largest moon of Jupiter and the third in the solar system. Diameter of 4821 km, mass 1.08 × 10²³, an average orbital radius of 1 882 700 km and an orbital period of 16.69 days.

On the picture above, the orbits of the Galilean moons are shown in red and the other satellites of Jupiter in blue. The differences in the size of the satellites orbits and the distances between the objects are incorrect. The image aims only to create awareness about the arrangement.

Io, Europa and Callisto are the names of the lovers of Zeus, supreme god of the Greek mythology, in the Roman mythology the equivalent is the god Jupiter.

Io is the daughter of the river god Inachus, turned into a white heifer. She was prisoned by Hera under the guard of a monster with many eyes Argus. Later has escaped and crossing the Bosphorus, gave its name.

Europa was Phoenician noble, daughter of the Phoenician king Agenor, kidnapped by Zeus and ported on the island of Crete, later she became queen of the island.

Callisto was a nymph of Arcadia, transformed into a bear by the jealous wife of Zeus, the goddess Hera.

Ganymede is the name of the son of the Trojan king Tros and the nymph Callirrhoe from Greek mythology, he was the most beautiful among mortals.

The names of the moons were suggested by Simon Marius soon after their discovery, but were not used until the middle of 20th century. Before that the Galilean moons are called - Jupiter 1, 2, 3 and 4.

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Source:
Physics Observatory @ TAMU