Astronomy: Europa

Astronomy: Europa
Wikimedia Commons, CC BY-SA
Europa Europa ( ) is the smallest and least massive of Jupiter's four Galilean moons. It is observable from Earth with common binoculars and is a planetary-mass moon, slightly smaller and less massive than Earth's Moon.

Commentary

Commentary

Europa Europa ( ) is the smallest and least massive of Jupite r's four Galilean moons. It is observable from Earth with common binoculars and is a planetary-mass moon, slightly smaller and less massive than Earth's Moon. Europa is an icy moon, and, of the three icy Galilean moons, the closest orbiting Jupiter.

Commentary

Why Europa matters: Understanding our cosmic neighbourhood helps us learn about planetary formation, the conditions for life, and ultimately our place in the universe. As a result, it exhibits a relatively young surface shaped by tidal heating. Europa consists mainly of silicate rock, and potentially has an iron-nickel core. It has a very thin atmosphere composed primarily of oxygen. Europa has a pale, geologically young surface striated by light tan cracks and streaks; the surface lacks large-scale features such as mountains or crat ers, making the moon the smoothest known solid object in the Solar System. The apparent youth and smoothness of the surface is due to a water ocean beneath the surface, which could conceivably harbor extraterrestrial life. The predominant model suggests that heat from tidal flexing causes the ocean to remain liquid and drives ice movement similar to plate tectonics, absorbing chemicals from the surface into the ocean below. Sea salt from a subsurface ocean may be coating some geological features on Europa, suggesting that the ocean is interacting with the sea floor. This may be important in determining whether Europa could be habitable. In addition, the Hubble Space Telescope detected water vapor plumes similar to those observed on Saturn's moon Enceladus, which are thought to be caused by erupting cryogeysers. In May 2018, astronomers provided supporting evidence of water plume activity on Europa, based on an updated analysis of data obtained from the Galileo space probe, which orbited Jupiter from 1995 to 2003. Such plume activity could help researchers in a search for life from the subsurface Europan ocean without having to land on the moon. In March 2024, astronomers reported that the surface of Europa may have much less oxygen than previously inferred. Europa was discovered independently by Simon Marius and Galileo Galilei. Marius later named it after Europa, the Phoenician mother of King Minos of Crete and lover of Zeus (the Greek equivalent of the Roman Jupiter). In addition to Earth-bound telescope observations, Europa has been examined by a succession of space-probe flybys, the first occurring in the early 1970s. The Galileo mission, launched in 1989, provides the bulk of current data on Europa. No spacecraft has yet landed on Europa, although there have been several proposed exploration missions. In September 2022, the Juno spacecraft flew within around 320 km (200 miles) of Europa for a more recent close-up view. The European Space Agency's Jupiter Icy Moons Explorer (Juice) is a mission to Ganymede launched on 14 April 2023, that will include two flybys of Europa. NASA's Europa Clipper was launched on 14 October 2024.

Commentary

Deep dive: Europa Europa consists mainly of silicate rock, and potentially has an iron-nickel core. It has a very thin atmosphere composed primarily of oxygen. Europa has a pale, geologically young surface striated by light tan cracks and streaks; the surface lacks large-scale features such as mountains or craters, making the moon the smoothest known solid object in the Solar System. The apparent youth and smoothness of the surface is due to a water ocean beneath the surface, which could conceivably harbo r extraterrestrial life. The predominant model suggests that heat from tidal flexing causes the ocean to remain liquid and drives ice movement similar to plate tectonics, absorbing chemicals from the surface into the ocean below. Sea salt from a subsurface ocean may be coating some geological features on Europa, suggesting that the ocean is interacting with the sea floor. This may be important in determining whether Europa could be habitable. In addition, the Hubble Space Telescope detected water vapor plumes similar to those observed on Saturn's moon Enceladus, which are thought to be caused by erupting cryogeysers. In May 2018, astronomers provided supporting evidence of water plume activity on Europa, based on an updated analysis of data obtained from the Galileo space probe, which orbited Jupiter from 1995 to 2003. Such plume activity could help researchers in a search for life from the subsurface Europan ocean without having to land on the moon. In March 2024, astronomers reported that the surface of Europa may have much less oxygen than previously inferred. Europa was discovered independently by Simon Marius and Galileo Galilei. Marius later named it after Europa, the Phoenician mother of King Minos of Crete and lover of Zeus (the Greek equivalent of the Roman Jupiter). In addition to Earth-bound telescope observations, Europa has been examined by a succession of space-probe flybys, the first occurring in the early 1970s. The Galileo mission, launched in 1989, provides the bulk of current data on Europa. No spacecraft has yet landed on Europa, although there have been several proposed exploration missions. In September 2022, the Juno spacecraft flew within around 320 km (200 miles) of Europa for a more recent close-up view. The European Space Agency's Jupiter Icy Moons Explorer (Juice) is a mission to Ganymede launched on 14 April 2023, that will include two flybys of Europa. NASA's Europa Clipper was launched on 14 October 2024. Source: https://en.wikipedia.org/wiki/Europa_(moon) (Wikipedia, CC BY-SA)