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Greek Mythology Notes

Io

💭 conceptMoonἸώ
Astronomy and mythology

A moon of Jupiter named after Io, the priestess of Hera whom Zeus transformed into a white cow, now ‌​‌​‍​‍​‌​‌​‍​‌​‌​‍​‌​‌​‍​‍​‌​‍​‍​‌​‍​‌​‌​‌​‌​‌​‍​‍​‌​‌​‌​‍​‌​‍known as the most volcanically active body in the solar system

The Meaning of Io

Io is the innermost of Jupiter's four Galilean moons and the most volcanically active body in the entire solar system.‌​‌​‍​‍​‌​‌​‍​‌​‌​‍​‌​‌​‍​‍​‌​‍​‍​‌​‍​‌​‌​‌​‌​‌​‍​‍​‌​‌​‌​‍​‌​‍ It was named after Io, a priestess of Hera at Argos, whom Zeus seduced. To hide his affair from Hera, Zeus transformed Io into a beautiful white cow. Hera, suspicious, demanded the cow as a gift and set the hundred-eyed giant Argus Panoptes to guard her. Zeus sent Hermes to lull Argus to sleep and slay him, but Hera then sent a gadfly to torment Io, driving her to wander across the world in misery — crossing what would be called the Bosporus ("cow-ford") and the Ionian Sea, both named after her journey. Io eventually reached Egypt, where Zeus restored her human form and she bore his son Epaphus, ancestor of the Egyptian royal line. The moon Io's intense volcanic activity — with over four hundred active volcanoes — is caused by tidal heating from Jupiter's massive gravitational field, which flexes the moon's interior. Io's surface is constantly reshaped by eruptions, making it one of the most dynamic environments in the solar system.

Parents

None recorded

Symbols

cowvolcanoeswandering

Fun Fact

Io has over four hundred active volcanoes, making it the most geologically active body in the solar system — its entire surface is remade by eruptions every million years

Explore Further

Europa

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Astronomy and mythology

A moon of Jupiter named after Europa, the Phoenician princess abducted by Zeus in the form of a white bull, now one of the most promising candidates for extraterrestrial life

europaeurope

Callisto

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Astronomy and mythology

A moon of Jupiter named after Callisto, the nymph companion of Artemis who was transformed into a bear and placed among the stars as the constellation Ursa Major

Ganymede

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Astronomy and mythology

The largest moon in the solar system, named after Ganymede, the beautiful Trojan prince abducted by Zeus to serve as cupbearer of the gods on Olympus

ganymede

Triton

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Astronomy and mythology

The largest moon of Neptune, named after Triton, the merman son of Poseidon, notable for being the only large moon in the solar system that orbits in the opposite direction to its planet

triton

Charon

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Astronomy and mythology

The largest moon of Pluto, named after Charon, the ferryman who transported the souls of the dead across the River Styx to the underworld of Hades

charon

Jupiter

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Astronomy and mythology

The largest planet in the solar system, named after Jupiter, the Roman king of the gods identified with the Greek Zeus, because of its commanding size and brightness

jupiterjovial

Saturn

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Astronomy and mythology

The sixth planet from the Sun, named after Saturn, the Roman god of agriculture and time identified with the Greek Titan Kronos, father of Zeus

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Aphrodite

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Astronomy and mythology

The planet Venus is named after the Roman equivalent of Aphrodite, the Greek goddess of love and beauty, because it is the brightest and most beautiful object in the night sky after the Moon

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Venus

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Astronomy and mythology

The second planet from the Sun and the brightest natural object in the night sky after the Moon, named after Venus, the Roman goddess of love identified with the Greek Aphrodite

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Pluto

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Astronomy and mythology

A dwarf planet named after Pluto, the Roman god of the underworld identified with the Greek Hades, chosen because of its extreme distance and darkness at the edge of the solar system

plutoplutonian

Uranus

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Astronomy and mythology

The seventh planet from the Sun, named after Ouranos, the primordial Greek god of the sky and the earliest supreme deity in the mythological genealogy

uranus

Goddess of the Moon

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Moon, night sky, lunar cycles

Selene drives her silver chariot across the night sky, illuminating the world with reflected light.

selenelunamoon