NASA suggests a magnetic shield to safeguard Mars’ atmosphere

NASA Plans to Use a Magnetic Shield to Help Restore Mars’ Atmosphere and Support Human Missions

TL;DR

NASA has proposed using a magnetic shield to restore Mars’ atmosphere and enable human exploration by the 2030s. This magnetic shield would be placed at the Mars L1 Lagrange Point to protect the planet from solar winds, allowing its atmosphere to thicken over time. The process could warm the planet, melt ice caps, and restore some of Mars’ lost water, creating better conditions for human colonization.

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NASA suggests using a magnetic shield to preserve Mars’ atmosphere.

NASA’s Planetary Science Division (PSD) recently held a “Planetary Science Vision 2050 Workshop” at its headquarters in Washington, DC. This event gathered scientists and researchers from around the globe to participate in discussions and presentations about the future of space exploration.

One of the most compelling presentations focused on the exploration of Mars by astronauts. During this talk, titled “A Future Mars Environment for Science and Exploration,” NASA Director Jim Green discussed how deploying a magnetic shield could boost Mars’ atmosphere and support future human missions there.

The prevailing scientific view is that Mars, like Earth, once had a magnetic field that protected its atmosphere. However, about 4.2 billion years ago, Mars’ magnetic field vanished, leading to the gradual loss of its atmosphere into space. Over the next 500 million years, Mars transitioned from a warm, wet planet to the cold, barren world we see today.

This theory has been reinforced by data from orbiters such as the European Space Agency’s Mars Express and NASA’s MAVEN, which have been examining the Martian atmosphere since 2004 and 2014, respectively. These missions confirmed that solar wind played a major role in depleting Mars’ atmosphere, and they continue to measure the rate at which the planet’s atmosphere is escaping today.

Without this atmosphere, Mars will remain a frigid, dry environment unsuitable for life. This also poses serious risks for future crewed missions – which NASA aims to send by the 2030s. The main dangers will be exposure to radiation and the risk of asphyxiation, which could become even greater for potential colonists.

To address these concerns, Dr. Jim Green and a group of researchers proposed an ambitious solution. They suggested placing a magnetic dipole shield at the Mars L1 Lagrange Point, creating an artificial magnetosphere around the entire planet to protect it from solar winds and radiation.

Green and his team acknowledged that the concept may sound “fanciful,” but they emphasized that new research into miniature magnetospheres (to protect spacecraft and crews) supports the idea:

“This new research is emerging thanks to advances in plasma physics and lab experiments. In the future, inflatable structures could potentially create a magnetic dipole field of 1 to 2 Tesla (10,000 to 20,000 Gauss), effectively shielding against the solar wind.”

Positioning this magnetic shield would protect two critical regions where Mars’ atmosphere is mostly lost. During the presentation, Green and his team pointed out that these escape routes are located “over the northern polar cap, involving higher energy ionospheric particles, and in the equatorial zone, where lower-energy oxygen ions are escaping at a rate of 0.1 kg/s.”

To test their idea, the research team – including experts from Ames Research Center, Goddard Space Flight Center, the University of Colorado, Princeton University, and the Rutherford Appleton Laboratory – ran a series of simulations at the Coordinated Community Modeling Center (CCMC), which specializes in space weather studies. These simulations assessed the effect of their proposed artificial magnetosphere.

Their findings showed that a dipole field positioned at the Mars L1 Lagrange Point could effectively counteract the solar wind, leading to a balanced atmosphere on Mars. Currently, volcanic outgassing from Mars’ interior and crust partially replenishes its atmosphere, which stands at about 6 mbar of air pressure (less than 1% of Earth’s sea-level pressure).

As a result, Mars’ atmosphere would naturally thicken over time, unlocking new opportunities for human exploration and colonization. Green and his team estimated that the temperature could rise by about 4°C (7°F), enough to melt the carbon dioxide ice in the northern polar ice cap. This would trigger a greenhouse effect, further warming the planet and melting the water ice in the polar caps.

According to their calculations, these changes could restore about 1/7th of the oceans Mars had billions of years ago. While this may sound like the first steps toward terraforming, these changes would significantly aid human exploration in the coming decades.

“A significantly enhanced Martian atmosphere, both in pressure and temperature, would be enough to allow for surface liquid water and offer many benefits for science and human exploration in the 2040s and beyond,” Green explained. “Much like on Earth, a thicker atmosphere would allow for heavier equipment to be landed, shield against cosmic and solar radiation, extend the ability to extract oxygen, and enable ‘open-air’ greenhouses for plant production, among other benefits.”

These improved conditions would also allow scientists to conduct more detailed studies of Mars, exploring its potential for habitability, as traces of water and past life would gradually re-emerge in the landscape. Achieving this in the coming decades could pave the way for Mars colonization.

In the meantime, Green and his colleagues plan to refine their simulation results to provide a more precise estimate of how long these changes might take. Conducting cost analyses of the magnetic shield would also be a logical next step. Although this idea may seem like science fiction, running the numbers is always a good start!