The Milky Way can be full of planets with oceans and continents like here on Earth

Astronomers have long studied the vast universe in hopes of discovering alien civilizations. But for a planet to have life, liquid water must be present. The chances of this discovery scenario seem impossible to calculate, as planets like Earth have been supposed to get water by chance if a large ice asteroid hits the planet.

Now, researchers at the GLOBE Institute at the University of Copenhagen have published an open-ended study indicating that water may be present during the very formation of a planet. According to the study’s calculations, this is true for both Earth and Venus and Mars.

“All our data suggest that water was part of the building blocks of the Earth, from the beginning. And because the water molecule occurs frequently, there is a reasonable probability that it will apply to all The decisive point for whether there is liquid water is the distance from the planet to its star, “said Professor Anders Johansen of the Center for the Formation of Stars and Planets, who led the study published in the study. magazine. Scientific advances.

Using a computer model, Anders Johansen and his team have calculated how quickly the planets form and from which building blocks. The study indicates that they were particles of ice dust and millimeter-sized carbon, which are known to orbit all the young stars in the Milky Way, which accumulated 4.5 billion years ago in the formation of what would later become the Earth.

To the point that the Earth had grown to 1 percent of its current mass, our planet grew by capturing masses of pebbles full of ice and carbon. The Earth grew faster and faster until, five million years later, it became as big as we know it today. Along the way, the temperature on the surface rose sharply, causing the ice of the pebbles to evaporate as it descended to the surface, so that currently only 0.1 percent of the planet is made up of water, even though 70 per cent of the Earth’s surface is covered by water, ’says Anders Johansen, who together with his Lund research team ten years ago presented the theory now confirmed by the new study.

The theory, called “pebble accretion,” is that planets are made up of pebbles that cluster together and that planets grow more and more.

Anders Johansen explains that the H2O water molecule is found all over our galaxy and that, therefore, the theory opens up the possibility that other planets may have formed in the same way as Earth, Mars and Venus.

“All the planets in the Milky Way can be made up of the same building blocks, meaning that planets with the same amount of water and carbon as Earth, and therefore potential places where there can be life, are they frequently occur around other stars in our galaxy, as long as the temperature is right, ‘he says.

If the planets in our galaxy had the same building blocks and the same temperature conditions as Earth, there will also be a good chance that they have about the same amount of water and continents as our planet.

Professor Martin Bizzarro, co-author of the study, says:

“With our model, all the planets get the same amount of water, and this suggests that other planets may have not only the same amount of water and oceans, but also the same amount of continents as here on Earth. good opportunities for the emergence of life ’, he says.

If, on the other hand, the amount of water on the planets was random, the planets could look very different. Some planets would be too dry to develop life, while others would be completely covered by water.

“A planet covered by water, of course, would be good for marine beings, but it would offer less-than-ideal conditions for the formation of civilizations that can observe the universe,” says Anders Johansen.

Anders Johansen and his research team look forward to the next generation of space telescopes, which will offer much better opportunities to observe exoplanets orbiting a star other than the Sun.

The new telescopes are powerful. They use spectroscopy, which means that by observing what kind of light is blocked from the orbit of the planets around their star, you can see how much water vapor there is. It can tell us something about the number of oceans on this planet, ‘he says.

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