Discoveries

March 01, 2022

The Super-Earths

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Astronomers have discovered thousands of exoplanets scattered across the galaxy, including “super-Earths.”

These types of planets range between the sizes of Earth and Neptune but scientists remain puzzled as to whether they are rocky like our world or gas giants.

There are more questions over whether they can host life. As a result, a research team decided to study if super-Earths were equipped with a magnetic field, Forbes reported.

One of the main reasons Earth is habitable is because of its magnetic field – or magnetosphere – generated by the convective motion of molten iron in the planet’s outer core. This protective field defends the planet from harmful solar winds that can be detrimental to life.

For their study, lead author Richard Kraus and his team recreated the pressures found at the center of super-Earths using one of the world’s most powerful lasers.

The process showed that the melting point of iron in these planets is up to 1000 gigapascals (Gpa), which is about three times the pressure of Earth’s core.

Kraus suggested that this high melting point means the liquid metal core lasts the longest on terrestrial exoplanets about four to six times Earth’s mass. He added that this also means that a super-Earth’s magnetosphere is longer lasting and possibly able to host life.

But the authors cautioned that more research needs to be conducted before people prepare their voyage to colonize a super-Earth.

This story originally appeared in the March 01, 2022 newsletter, Profiles in Courage.