With its wide seas and lovely lakes, it's simple to imagine that Earth is a water world, yet in comparison to other planets, Earth is unusually moist. Even Jupiter's and Saturn's cold moons contain more liquid water than Earth does. The fact that liquid water exists on Earth in the heated habitable zone of the Sun makes it exceptional, not because liquid water exists on Earth. Additionally, as a recent research published in Nature Communications suggests, Earth could be considerably more unique than previously believed.

One of the more prevalent molecules in the universe is water. The most prevalent element in the universe is hydrogen, and oxygen can be easily created as part of the stellar CNO fusion cycle. Therefore, we would anticipate finding many water-rich planets in star systems. But it doesn't mean there will be an abundance of liquid water. Two different types of planets contain liquid water in our solar system. Moons of gas giants and Earth.

Earth formerly possessed liquid water, much like other warm terrestrial planets like Venus and Mars do now. The surface of Mars is too tiny to hold water. While some of it froze into the planet's crust, most of it dissipated into space. Although Venus was large enough to hold water, its intense heat caused much of it to evaporate into its dense atmosphere. Although the exact mechanism by which Earth managed to keep its seas is still unknown, it was probably a mix of a powerful magnetic field and more water from asteroids and comets during the time of intense bombardment.

Another tale involves the cold moons of Jupiter and Saturn. They kept the water from their development because they were far enough from the Sun. To stop water from evaporating into space, they swiftly created a thick covering of ice. These moons, however, are tiny planets that, if it weren't for the tidal forces generated by their gas giant, would have swiftly frozen solid.

The common consensus is that we would be much more likely to find life on a world like Europa than one like Earth because cold gas planets are likely to have icy moons. However, one recent study begs to disagree. It contends that super-Earths are far more likely to have liquid water than regular Earths.

Super-Earths have masses ranging from a few Earth masses to that of Neptune. They are probably enormous, gas-filled planets with dense atmospheres. They probably resemble Earth more on the tiny end. Super-Earths are by far the most prevalent exoplanets, at least based on those we've discovered so far. And the bulk of them are probably found in the colder parts of the solar system, outside the habitable zone of their star. They are therefore probably water-rich. However, they are also unlikely to be discovered in an orbit around a gas giant, therefore it has usually been considered that their ice covering would eventually become mostly frozen solid.

The varied freezing and melting points of ice are the cause. Our planet's ice kind melts at about 0 degrees Celsius. But only in the region of Earth's atmosphere is this true. There are several types of ice with various melting points at greater pressures. Although it's a little tricky, generally speaking, ice can have a melting point that is significantly higher at greater pressures. Therefore, even if a super-Earth had active geology, it might not be hot enough to melt ice.

This new study demonstrates that super-Earths do not need to be extremely hot in order to form a deep ocean. It may melt a tiny layer of water at its surface by geothermal and nuclear heating, and because of fissures and different water phase transitions, water can wick up to the layer just below the frozen surface. A liquid ocean layer might be produced using only this approach. A super-Earth could be able to sustain a liquid ocean long enough for life to develop since its heat can persist billions of years.

Super-Earth seas may be 100 times more prevalent than those of Earth-like worlds or ice moons, according to what is known about exoplanets. Thus, there are many more potential habitats for life than previously believed.

This article was originally published on Universe Today by Brian Koberlein. Read the original article here.