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- Super-Earths are rocky exoplanets<\/strong> larger than Earth but smaller than Neptune. Could they support life?<\/li>\n
- Super-Earths could have powerful magnetic fields<\/strong> stronger than Earth\u2019s magnetic field. Magma oceans beneath their surfaces could generate them.<\/li>\n
- These magnetic fields could help shield the surface<\/strong> \u2013 and possible life \u2013 from their stars\u2019 intense radiation, just as Earth\u2019s magnetic field protects us.<\/li>\n<\/ul>\n
EarthSky\u2019s 2026 lunar calendar is available now. Get yours today! Makes a great gift.<\/p>\n
Powerful magnetic fields on super-Earths?<\/h3>\n
Super-Earths \u2013 or rocky exoplanets between Earth and Neptune in size \u2013 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 \u2013 and any potential life \u2013 from deadly radiation from their stars.<\/p>\n
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\u2019s radiation, just as happens on Earth.<\/p>\n
The research team published its intriguing peer-reviewed findings in Nature Astronomy<\/em> on January 15, 2026.<\/p>\n
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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<\/p>\n
\u2014 Science X \/ Phys.org (@sciencex.bsky.social) 2026-01-15T15:49:51-05:00<\/p>\n<\/blockquote>\n
Magma oceans and strong magnetic fields on super-Earths<\/h3>\n
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?<\/p>\n
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\u2019s. As lead author Miki Nakajima at the University of Rochester explained:<\/p>\n
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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\u2019t 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.<\/p>\n<\/blockquote>\n
![\"Volcanic](\"https:\/\/earthsky.org\/upl\/2024\/11\/L9859d-superearth-exoplanet-artist-concept.jpeg\")
Artist\u2019s concept of L 98-59 d, a super-Earth world 35 light-years away. Image via NASA.<\/figcaption><\/figure>\n Simulating super-Earth magnetic fields<\/h3>\n
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.<\/p>\n
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\u2019s Laboratory for Laser Energetics. They then combined the data with quantum mechanical simulations and planetary evolution models.<\/p>\n
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\u2019s. In addition, the magnetic field could last for billions of years. That\u2019s good news in terms of potential habitability. Nakajima said:<\/p>\n
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This work was exciting and challenging, given that my background is primarily computational and this was my first experimental work. I\u2019m 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.<\/p>\n<\/blockquote>\n
![\"Smiling](\"https:\/\/earthsky.org\/upl\/2026\/01\/Miki-Nakajima-University-of-Rochester.png\")
Miki Nakajima at Rochester University in New York led the new study about super-Earths and their magnetic fields. Image via University of Rochester.<\/figcaption><\/figure>\n Potentially habitable super-Earths<\/h3>\n
There\u2019s still a lot we don\u2019t 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?<\/p>\n
But a powerful magnetic field would be hugely beneficial. Just as Earth\u2019s magnetic field helps protect life on the surface by blocking deadly radiation from the sun, the same could apply to super-Earths.<\/p>\n
Super-Earths are surprisingly common<\/h3>\n
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\u2019t have one. But that makes them all the more intriguing. <\/p>\n
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.<\/p>\n
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.<\/p>\n
Source: Electrical conductivities of (Mg,Fe)O at extreme pressures and implications for planetary magma oceans<\/p>\n
Via University of Rochester<\/p>\n
Read more: Super-Earth 18 light-years away sparks hope for life in space<\/p>\n
Read more: Eyeball ocean world? Webb reveals an intriguing super-Earth<\/p>\n<\/div>\n
\n - Super-Earths could have powerful magnetic fields<\/strong> stronger than Earth\u2019s magnetic field. Magma oceans beneath their surfaces could generate them.<\/li>\n