The Road To Europa!

Europa!

Europa is Jupiter's fourth-largest natural satellite and the sixth-largest moon in the solar system. Europa is a fantastic frigid world of ice with a probable ocean that could hold twice as much water as all of Earth's oceans combined! NASA has a planned mission which has been named the Europa Clipper, which is to perform multiple flybys of Europa while it stays in orbit around Jupiter. So, in celebration of the upcoming mission in 2024, here are some need-to-know facts about Europa and its makeup as a celestial body.

Europa facts

Average surface temperature: -160 degrees Celsius (-260 degrees Fahrenheit)

The average distance from the Sun: 5.2 AU

Diameter: 1,940 miles (3,100 kilometers), slightly smaller than Earth's moon

Volume: 15.9 billion cubic kilometers (3.8 billion cubic miles)

Gravity: 1.315 m/s2

Solar day: 3.5 Earth days

Solar year: about 12 Earth years

Atmosphere: Extremely tenuous, mostly oxygen

The discovery of Europa: 

The discovery of Europa is quite interesting! Galileo discovered Europa on January 8th, 1610. However, it is possible he discovered it a day earlier, on January 7th. Still, he couldn't differentiate between Io (another one of Jupiter's moons) and Europa because he was using a low-powered telescope. Later, he observed and found out for himself that they were two separate natural satellites/celestial bodies. 

This discovery was quite a large one in the religious realm because the Catholic and Christian churches believed everything orbited the Earth. This was an idea that was also supported by Aristotle and Ptolemy. Galileo finding these other celestial bodies orbiting their planets and observing that Venus went through phases similar to our moon gave us strong evidence against the geocentric model and pointed towards Nicolaus Copernicus' heliocentric model. 

The characteristics of Europa: 

The characteristics are just as interesting as its discovery, if not more interesting! The characteristics of this natural satellite are quite attractive to most astronomers and astrobiologists due to the high probability of water beneath its icy surface. Europa has all the fundamental chemistry needed to produce life, which is the ticket that interests all scientists around due to its possibilities. However, it gets blasted by radiation from Jupiter, so what life could survive? The theories are it has a highly sustainable ocean life fueled by the radiation from Jupiter rather than the process of photosynthesis. So the ocean life on Europa could be powered by chemical reactions rather than photosynthesis. There's a very high expectation of water under the surface suggested by the assumed vapor plumes found by the Hubble Space Telescope, but that isn't the only thing that suggests a giant body of water under the surface of that ice! The cracks also give us a tad bit of a hint to it as well (but we'll talk about that in a bit). Another characteristic is the fact it has fluctuations in its magnetic field, which indicates a conductor of some kind.

Now back to the ocean: The surface of Europa is covered in cracks, which most believe is caused by tidal forces on the possible oceans deep below the surface. It's a high probability and possibility that when Europa orbits Jupiter and it becomes close to the planet, the ocean rises and falls in certain areas, causing the cracked ice we see on the natural satellite's surface. 

Also, another exciting thing about Europa is that in 2014 it was found that it could possibly host a form of plate tectonics! Earth is the only known body in the solar system with a dynamic crust, which is considered necessary for the development and evolution of life on our planet.

Overall, Europa is pretty stellar! Come back to this post for updates on facts and more space puns! :)