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

Astronomers have long looked into the vast universe in hopes of discovering extraterrestrial civilizations. But for a planet to have life, there must be liquid water. The chances of this finding scenario seemed impossible to calculate, because it was the assumption that planets like Earth get their 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 eye-opening study, indicating that water may be present even during the formation of a planet. According to the study’s calculations, this is true for both Earth, Venus and Mars.

“All our data suggest that water was part of the earth’s elements from the very beginning. And because the water molecule occurs frequently, there is a reasonable probability that it will apply to all the planets in the Milky Way. The decisive point for the presence of liquid water is the distance of the planet from its star ‘, says professor Anders Johansen from the Center for the Formation of Stars and the Planet who led the study published in the journal. Scientific advances.

Using a computer model, Anders Johansen and his team calculated how fast the planets formed and from which blocks. The study indicates that it was millimeter-sized particles of ice dust and carbon – known to orbit all the young stars in the Milky Way – that 4.5 billion years ago gathered in the formation of what it would later become Earth.

“By the time the Earth grew to a percentage of its current mass, our planet grew by capturing masses of pebbles filled with ice and carbon. The earth then grew faster and faster until, after five million years, it became as big as we know it today. Along the way, the surface temperature rose sharply, causing ice in the pebbles to evaporate as it descended to the surface, so that today only 0.1% of the planet is made up of water, even though 70% of the surface is covered. ‘says Anders Johansen, who together with his research team in Lund ten years ago presented the theory that the new study now confirms.

The theory, called “pebble accretion,” is that the planets are made up of clumping pebbles and that the planets are growing larger and larger.

Anders Johansen explains that the H2O water molecule is found everywhere in our galaxy, and therefore the theory opens up the possibility that other planets were 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, which means that planets with the same amount of water and carbon as Earth – and therefore potential places where life can be present – frequently appear around other stars. from our galaxy, provided the temperature is right, ‘he says.

If the planets in our galaxy have 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 receive 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. It offers good opportunities for the emergence of life, ‘he says.

If, on the other hand, it happened how much water was present on the planets, the planets could look very different. Some planets would be too dry to develop life, while others would be completely covered by water.

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

Anders Johansen and his research team are looking forward to the next generation of space telescopes, which will provide 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 that planet, ‘he says.

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