Four centuries after Galileo Galilei was amazed to discover four moons around Jupiter, space probes and powerful telescopes have allowed us to learn facts that would never have crossed the Italian astronomer's mind, such as the volcanic surface of Io or the subterranean oceans of Europa, Ganymede and Callisto hidden under icing. Two new missions from the European Space Agency (ESA) and NASA promise to uncover more surprises about Jupiter's moons in the next decade.
Jupiter's nearest moon, Io, at a distance of about 422,000 kilometers, is the most active body in the solar system. The cause of this geological activity is the heat created by the gravitational pull it feels when it is between the planet and the other large moons - Europa and Ganymede.
“Eruption plumes were observed by Voyager 1 , Galileo spacecraft and New Horizons . NASA's Galileo spacecraft also observed surface lava flows,” said Emma Marcucci, researcher and science communicator at the Space Telescope Science Institute (USA), in a conversation with OpenMind
Io's permanent volcanic activity prevents the formation of craters and gives them striking colors. Ground-based telescopes have revealed that its atmosphere fluctuates when orbit puts it in the planet's shadow. This thin layer, composed mostly of carbon dioxide emitted by volcanoes, collapses when eclipsed by the gas giant, but is restored once more when the moon receives sunlight.
Source: Laura Chaparro; SCIENCE SCIENTIFIC INSIGHTS
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