According to Countryaah.com, Europe is located in the northern hemisphere of the globe. Europe is the fourth largest of Jupiter’s 79 moons. It is the sixth largest moon in the solar system, just after Earth’s own moon. Europe is the most likely place to find liquid water in the solar system except here on Earth. The surface is covered by a several-kilometer-thick layer of water, and there is probably an even thicker layer of liquid salt water under the ice.

Structure

Europe has a diameter of 3121 km and an average mass density of 3.01 g/cm ³, which is about 90% of the diameter and density of our own moon. The structure of Europe is believed to be similar to that of the Earth.

Based on Abbreviationfinder, Europe has a metallic core surrounded by a mantle of silicate rocks. The surface is covered by a layer of 15 to 25 km thick water. Among other things, measurements of how the magnetic field of Jupiter is changing around Europe, it is estimated that there is a 60 to 150 km thick floating layer of salt water under the ice, covering the entire moon. Europe is so far away from the Sun that the surface temperature is very low, below –160 °C, which means that the water under the ice should also be frozen. But the seas of Europe are probably kept afloat due to heat generated by the tidal forces of Jupiter and made with ice insulating from above. In addition, there are potential radioactive elements in the core of Europe that can heat the sea from the inside through deep-sea valves, similar to the hot springs we have on the seabed here on Earth.

Because Europe’s underground ocean is so deep, it can be up to twice as much water in Europe as all the water we have here on Earth, even though the diameter of Europe is only a quarter of Earth’s diameter.

Court

Europe walks in an almost circular orbit around Jupiter with eccentricity of 0.0094, average distance of 670 900 km and average orbit speed of 13.7 km/s. Europe has a fixed rotation, which means that the rotation period is equal to the turnaround time of 3.55 days around Jupiter. This means that the same side of Europe always points towards Jupiter, just as our moon always faces the same side towards Earth. The orbits of the three Jupiter moons Io, Europa and Ganymedes are locked to each other in such a way that their turnaround times are in a 1: 2: 4 ratio (triple resonance). Together with Jupiter’s tidal forces, this contributes to tensions that create Io’s volcanism and make Europe’s surface burst. Because Jupiter and Europe have coherent orbits and rotational axes that are almost normal on the orbit, Europe has almost no seasonal differences during the 12 years Jupiter uses in its orbit of the Sun.

Jupiter itself orbits the Sun with an average distance of 780 million km, 5.2 times longer than the distance between the Sun and the Earth. Thus, it takes about 42 minutes for light to travel from the Sun all the way to Jupiter and Europe, and the light level is about 1/25 of the light level on Earth.

Exploration and surface

Europe, together with the three neighboring moons Io, Ganymede and Callisto, was discovered by Galileo Galilei in 1610 when he aimed his homemade telescope at the sky. This was the first time objects were observed in orbit around celestial bodies other than the Earth, which in the prevailing geocentric worldview at that time was believed to be the center of the universe. Galileo’s observation of Jupiter’s moons was an important argument for Nicolaus Copernicus ‘ heliocentric model, and helped launch the known conflict between Galileo Galilei and the Catholic Church.

Along with the neighboring moons, Europe was imaged up close in 1979 by the two American Voyager probes. During the period 1995–2000, the moons have been mapped with a resolution of at least one km from the Galileo space probe. Europe’s surface appears as a deserted, reddish-brown ice surface, intersected by a complicated network of cracks and grooves that stretch for hundreds of miles. The color probably comes from salts and sulfur compounds that have been mixed into the ice and modified by high-energy Jupiter radiation. The complicated structure is probably due to the cracking of the ice mainly due to tidal forces from Jupiter, similar to plate tectonic movements here on Earth.

The surface of Europe is considered very young in a geological context. Europe has very few craters, which indicate that the surface is no more than 40 to 90 million years old. This is very young compared to Earth’s own moon, which is clearly full of craters, and is estimated to be 4.5 billion years old. One way to understand this is that the surface must be constantly changing, so that older craters are smoothed and erased by the movement of the ice. Without mountains and notable craters, the surface of Europe is the smoothest surface of all known bodies in the solar system.

Because of the icy surface of Europe, the moon is very reflective. With an albedo of 0.64, it reflects about 5.5 times as much light as the surface of our own moon does. So even though the light level is much lower at Jupiter, Europe will be relatively well visible in the night sky for a hypothetical observer standing on Jupiter.

Potential for life

Life, at least as we know it, requires at least three main ingredients: liquid water, appropriate chemical elements and an energy source. Here on Earth we have discovered closed, independent ecosystems in extreme conditions at the bottom of the ocean. These do not depend on the energy of the Sun, but survive on the energy of hot deep-sea valves. In Europe, there are precisely strong indications of large volumes of liquid water, with potential deep-sea valves, salt and sulfur compounds. Thus, Europe is often regarded as the best candidate we have for finding extraterrestrial life in the solar system. The icy moon appears to have the necessary building blocks for life to occur, and it is also close enough to Earth that we can examine it more easily with both telescopes and space probes.