Europa’s Surface (Jupiter’s Mysterious Icy Moon) – Illustration
Europa is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet of all the 79 known moons of Jupiter. It is also the sixth-largest moon in the Solar System. Europa was discovered in 1610 by Galileo Galilei. Europa orbits Jupiter at about 417,000 miles (671,000 kilometers) from the planet. Light from the Sun takes about 45 minutes to reach Europa. Because of the distance, sunlight is about 25 times fainter at Jupiter and Europa than at Earth.
Europa’s water-ice surface is crisscrossed by long, linear fractures. The surface of this moon appears to be no more than 40 to 90 million years old, which is youthful in geologic terms (the surface of Callisto, another of Jupiter’s moons, is estimated to be a few billion years old). Along Europa's many fractures, and in splotchy patterns across its surface, is a reddish-brown material whose composition is not known for certain, but likely contains salts and sulfur compounds that have been mixed with the water ice and modified by radiation. This surface composition may hold clues to the moon's potential as a habitable world.
Life on Europa could exist in its under-ice ocean, perhaps in an environment similar to Earth's deep-ocean hydrothermal vents. If we eventually find some form of life at Europa, it may look like microbes, or maybe something more complex. If it can be demonstrated that life formed independently in two places around the same star, it would then be reasonable to suspect that life springs up in the universe fairly easily once the necessary ingredients are present, and that life might be found throughout our galaxy, and the universe.
In October 2024, NASA will launch a spacecraft called Europa Clipper, which will use multiple flybys of the moon to investigate the habitability of this ocean world. The Europa Clipper orbiter will swoop around Jupiter on an elliptical path, dipping close to the moon on each flyby to conduct detailed reconnaissance. The science includes gathering measurements of the internal ocean, mapping the surface composition and its geology, and hunting for plumes of water vapor that may be venting from the icy crust.
Caption credit: NASA/Wikipedia
Learn more:
- https://go.nasa.gov/3un5K9w
- https://go.nasa.gov/3wtN7mr
- https://go.nasa.gov/39GTEQF
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