If you think Earth is the luckiest place of our solar system in terms of water quantity, you surely need to reconsider as it is not true.

The presence of liquid water is probably the most essential commodity for the existence of life. It is a primary criterion that needs to be fulfilled in order to judge whether a place can be considered a candidate for supporting life or not. Scientists are using this technique to filter out possible candidates that may support extra-terrestrial life for years now. Earth is suitable for different forms of life because it contains abundant supplies of liquid water. Having said that, there are other ocean worlds in our solar system that have plenty of more water than our planet.

Ocean worlds are also known as Ocean Planets and they are defined as astronomical objects that have a significant amount of water on its surface or subsurface. These heavenly bodies are keenly analyzed by astrobiologists as they have the potential to develop and support life. Some of them are so drenched with water that our planet will look like a desert in front of them. They have a far-fetched lead on Earth, both in terms of the total amount of water and the relative quantity of the liquid with respect to the size of the heavenly body. Some common examples of such places include Enceladus, Ganymede, and Europa. The details about each one of them are described below.

Enceladus

This moon of Saturn has a complete world of water beneath its surface. Scientists performed an in-depth analysis of Enceladus in order to know the exact quantity of water as the eruption of wonderful geysers was observed from its surface. They found that the unsteady movement of the moon can also be explained if we assume that it has water under its crust. The Cassini Space Probe of NASA extended this idea and showed the world that there is a complete ocean of water at Enceladus. This gave birth to another mystery. As the temperature of space is extremely cold in that part of our solar system, why did the water not freeze? A probable answer to this query, which gained quite a lot of appreciation, was that the tidal forces generated by the gravity of Saturn produce much more energy than what humanity anticipated. Carolyn Porco, the Head of the Imaging at Cassini, explained the importance of this theory by saying,

“This is a major step beyond what we understood about this moon before, and it demonstrates the kind of deep-dive discoveries we can make with long-lived orbiter missions to other planets. Cassini has been exemplary in this regard.”  

Ganymede

It is the largest moon of Jupiter and is the wettest ocean planet of our solar system. Liquid water accounts for nearly 46% of its volume. If we add icy parts of Ganymede, this figure goes up to 70%. Scientists announced about the presence of a salty ocean underneath its surface in light of the data gathered through the Hubble Space Telescope of NASA. The representatives of NASA also mentioned that it can have more water than the entire surface of Earth as it is 10 times deeper than the oceans of our planet. Some signs of flooding were also observed on the surface of the moon. Jim Green, the Director of Planetary Science at NASA, expressed his views in the following words:

“The solar system is now looking like a pretty soggy place.”

Europa

It is smaller than the Earth’s moon but Voyager provided evidence that Europa has twice as much water as our planet. It is one of the top contenders for harboring life as Hubble found plumes of water on this moon of Jupiter. Geoff Yoder, an Acting Associate Administrator of the Science Mission Directorate of NASA, acknowledged that as he said,

“Europa’s ocean is considered to be one of the most promising places that could potentially harbor life in the solar system. These plumes, if they do indeed exist, may provide another way to sample Europa’s subsurface.”

NASA is working on Europa Clipper these days which is expected to launch somewhere between 2022 and 2025. Similarly, the European Space Agency is busy with the Jupiter Icy Moons Explorer which probably will also leave our planet in 2022. This mission will cover both Europa and Ganymede.