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Black hole-sized magnetic fields could be created on Earth, study says

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Scientists should be able to create magnetic fields on Earth that rival the strength of those seen in black holes and neutron stars, a new study suggests. 

Such strong magnetic fields, which would be created by blasting microtubules with lasers, are important for conducting basic physics, materials science and astronomy research, according to a new research paper authored by Osaka University engineer Masakatsu Murakami and colleagues. The paper was published Oct. 6 in the open-access journal Scientific Reports.

Most magnetic fields on Earth, even artificial ones, are not particularly strong. The magnetic resonance imaging (MRI) used in hospitals typically produces fields of around 1 tesla, or 10,000 gauss. (For comparison, the geomagnetic field that swings compass needles to the north registers between 0.3 and 0.5 gauss.) Some research MRI machines use fields as high as 10.5 tesla, or 105,000 gauss, and a 2018 lab experiment involving lasers created a field of up to about 1,200 tesla, or just over 1 kilotesla. But no one has successfully gone higher than that. 

Related: 9 cool facts about magnets

Now, new simulations suggest that generating a megatesla field — that is, a 1 million tesla field — should be possible. Murakami and his team used computer simulations and modeling to find that shooting ultra-intense laser pulses at hollow tubes just a few microns in diameter could energize the electrons in the tube wall and cause some to leap into the hollow cavity at the center of the tube, imploding the tube. The interactions of these ultra-hot electrons and the vacuum created as the tube implodes leads to the flow of electric current. The flow of electric charges is what creates a magnetic field. In this case, the current flow can amplify a pre-existing magnetic field by two to

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NASA Mars probes discover billion-year-old dune fields frozen in time

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The HiRise camera on the Mars Reconnaissance Orbiter snapped these dune fields in Valles Marineris. They’re estimated to be a billion years old


NASA/JPL/University of Arizona

Mars has a roughly 4.5-billion-year history. Thanks to our robotic explorers, we have a good sense of its current climate and atmosphere. A new study of ancient sand dunes points to what it might have been like a billion years ago on the red planet. 

A team led by Planetary Science Institute (PSI) research scientist Matthew Chojnacki took a close look a wind-driven dune fields in Valles Marineris, an area of Mars known for its extensive canyons. The dunes appear to have been preserved through lithification, a geologic process that turns sediments into rock.

The team published a study on this window into the martian past in the journal JGR Planets in August. “Based on the dune deposit’s relationships to other geologic units and modern erosion rates we estimate these to be roughly a billion years old,” Chojnacki said in a PSI statement on Monday. 

An image from NASA’s Mars Reconnaissance Orbiter HiRise camera shows some of these intriguing dunes that now act like time capsules.  

The dunes bear a resemblance to current formations seen on Mars, which gives scientists clues to the conditions long ago. “Because of the duneforms’ size and spatial arrangements, which are not that much different to modern equivalents, we suggest that the climate and atmospheric pressure to have been similar to that of contemporary Mars,” Chojnacki said. 

The research adds to an ever-growing understanding of Mars’ geologic history and just how different the red planet is from Earth. While Mars