- Super-Earths are rocky exoplanets larger than Earth but smaller than Neptune. Could they support life?
- Super-Earths could have powerful magnetic fields stronger than Earth’s magnetic field. Magma oceans beneath their surfaces could generate them.
- These magnetic fields could help shield the surface – and possible life – from their stars’ intense radiation, just as Earth’s magnetic field protects us.
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Powerful magnetic fields on super-Earths?
Super-Earths – or rocky exoplanets between Earth and Neptune in size – might be more friendly to life than scientists thought. On January 15, 2026, researchers at the University of Rochester in New York said super-Earths might have powerful magnetic fields that help protect the surface – and any potential life – from deadly radiation from their stars.
On Earth, our protective magnetic field is generated by movement in the liquid iron outer core. But on super-Earths, the scientists said deep oceans of hot magma could produce the magnetic fields. If a super-Earth were habitable, then its magnetic field would shield any life present from the star’s radiation, just as happens on Earth.
The research team published its intriguing peer-reviewed findings in Nature Astronomy on January 15, 2026.
Molten rock layers deep within super-Earths may generate strong magnetic fields, potentially shielding these exoplanets from harmful cosmic radiation and enhancing their habitability. doi.org/hbj5pg
— Science X / Phys.org (@sciencex.bsky.social) 2026-01-15T15:49:51-05:00
Magma oceans and strong magnetic fields on super-Earths
Scientists have said super-Earths might not have the same kind of liquid iron outer core as Earth does. So could they still have magnetic fields?
The new study suggests they could, through a slightly different mechanism than what happens on Earth. These large rocky worlds could have a subsurface ocean of hot magma called a basal magma ocean. This magma could produce magnetic fields even stronger than Earth’s. As lead author Miki Nakajima at the University of Rochester explained:
A strong magnetic field is very important for life on a planet, but most of the terrestrial planets in the solar system, such as Venus and Mars, do not have them because their cores don’t have the right physical conditions to generate a magnetic field. However, super-Earths can produce dynamos in their core and/or magma, which can increase their planetary habitability.
Simulating super-Earth magnetic fields
To find out if super-Earths could have magnetic fields, the researchers needed to simulate conditions inside them. Super-Earths are larger than Earth, and so they have immense pressures inside them. That means they could have long-lasting basal magma oceans and, therefore, magnetic fields.
To test that hypothesis, the researchers studied molten rock under similar conditions to what would happen in a basal magma ocean inside a super-Earth. They conducted laser shock experiments at the University of Rochester’s Laboratory for Laser Energetics. They then combined the data with quantum mechanical simulations and planetary evolution models.
The result? They found that the molten rock became electrically conductive. In fact, the magma was able to produce a powerful magnetic field stronger than Earth’s. In addition, the magnetic field could last for billions of years. That’s good news in terms of potential habitability. Nakajima said:
This work was exciting and challenging, given that my background is primarily computational and this was my first experimental work. I’m very grateful for the support from my collaborators from various research fields to conduct this interdisciplinary work. I cannot wait for future magnetic field observations of exoplanets to test our hypothesis.
Potentially habitable super-Earths
There’s still a lot we don’t know about super-Earths. This includes whether they can truly be habitable. They are rocky like Earth, but bigger and more massive. How would that affect conditions on the surface?
But a powerful magnetic field would be hugely beneficial. Just as Earth’s magnetic field helps protect life on the surface by blocking deadly radiation from the sun, the same could apply to super-Earths.
Super-Earths are surprisingly common
Super-Earths are some of the most common exoplanets that astronomers have found so far. That was a bit surprising to astronomers, because our own solar system doesn’t have one. But that makes them all the more intriguing.
How many are there in our galaxy? How do they form? Can they support life? These are all questions that scientists are seeking the answers to. And if any of them are indeed confirmed to have magnetic fields, that will make them even more enticing in the search for life elsewhere.
Bottom line: A new study said powerful magnetic fields on super-Earths could help shield them from radiation from their stars, making them potentially more friendly to life.
Source: Electrical conductivities of (Mg,Fe)O at extreme pressures and implications for planetary magma oceans
Via University of Rochester
Read more: Super-Earth 18 light-years away sparks hope for life in space
Read more: Eyeball ocean world? Webb reveals an intriguing super-Earth