The worlds of water exist and abound in both the galaxy and the terrestrial ones

Imagine if the Earth didn't have so much land, but

.

Perhaps it would not be as we know it now, with seas, rivers and oceans flowing over the crust, but a planet made up of a vastly greater proportion of water,

.

It could be habitable, although not surely for species like ours.

Well, this kind of world exists and, in fact, is more common than previously thought.

The Spanish scientists Enric Pallé, a researcher at the Institute of Astrophysics of the Canary Islands (IAC), and Rafael Luque, from the University of Chicago,

and, in addition, have found that these exoplanets abound as well as the terrestrial ones.

This follows from a new study of 43 exoplanets, all of which orbit around M-type dwarf stars, the most abundant in the galaxy.

The finding has just been published in the journal

.

"We have tried to find out what the nature of small Earth-like planets is. It was thought that there were multitudes of sizes, masses and densities, and that there were planets of all categories. But we have confirmed that there are 43 known planets around the Earth. M dwarf stars and that

. It is the first time that this theory can be confirmed", explains Pallé.

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What the new study has shown is that there are as many

out there as there are lands.

Astrophysicists have focused their research on exoplanets with a size similar to the worlds that, in our Solar System, would be between Earth and Neptune.

In addition, they limited themselves to

(80% of the total), the M dwarfs, and analyzed their size and weight.

The result was revealing: 50% of the mass of the water worlds is liquid;

and the other half, of rock.

If we think only on the surface, it might seem that these planets are similar to ours, but the reality is that they have nothing to do with it: "

, while, in the aquatic worlds, is 50% of the planet's mass", says Pallé.

"It is the first proof that aquatic planets exist, that they are potentially habitable and that they are composed of a different structure than previously thought."

In 2012, the Hubble Space

analyzed the atmosphere of an exoplanet and astrophysicists considered that it was a new type of world never detected before: a world of water.

At the time,

that encompassed the entire surface.

Now, the research by Luque and Pallé has ruled out this hypothesis.

"The water is not lost in an ocean, but

," says Pallé.

"Although they had made discoveries about it, this is the first certainty we have that they are as common as terrestrial ones," continues his colleague Luque.

"The aquatic planets were forgotten, but the current planetary formation theories always predicted their existence. It was not until this investigation that it was possible to verify it," he adds.

"Aside from

, we've found that half of those worlds are terrestrial-density, and it gives us hope that we

. "

Is it possible, then, that there is life out there?

Both scientists answer yes, although, remember, there is no evidence to confirm it, continues Luque.

Pallé, for his part, maintains that "it is possible that there are areas where, below the surface, the water is in a liquid state. A priori, they are potentially habitable, but we have to investigate what their surface is like and in what layers it is distributed Water".

In the same way, Luque defends that one of the consequences of the research is to analyze the possibilities of habitability of these exoplanets: "We believe that the water of the

is not on their surface,

. Therefore, one of the consequences of this research is to theoretically study the habitability conditions that exist on these planets", points out Luque.

They have also verified that these new aquatic worlds

towards the closest parts of the star, "something that was thought not to be possible, but which we have indirectly confirmed."

Water exoplanets can only form behind the

, that is, the area of ​​a planetary system where water no longer evaporates, as it is not too close to its star.

At the same time, if it is too far away, it freezes.

Therefore,

cannot be anywhere.

But here too there is a new finding.

"Aquatic worlds can only be formed after the ice line, so that these large amounts of water exist. We have not detected them at long distances, but closer to their star, so they have had to migrate, with the passage of time, from the outermost parts of the disk to the inner ones. If the water of these planets were only on the surface -not mixed as we

", explains Luque.

After this finding, the next step for these researchers will be to analyze the planets that orbit stars as large as the Sun and see if this trend continues.

In addition, they intend to verify if this trend continues and find out more about the nature of these worlds with the new

Space Telescope .

Luque points out that "

with the Webb, and there are others that are also being seen with giant telescopes that will be ready in seven or eight years to discover the peculiarities of their atmosphere and its surface".

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