Speaking at the Planetary Science Vision 2050 Workshop conference in Washington, director of Nasa’s Planetary Science Division James Green said scientists from the space agency have proposed a plan to shield Mars from the Sun’s rays through an artificial magnetic field around the planet.
Involving a “magnetic shield” launched in a stable orbit between Mars and the Sun, it would be made of a large electric circuit powerful enough to generate an artificial magnetic field.
The shield would allow Mars to slowly restore its atmosphere over the course of a few years. Once an atmosphere had built up, the greenhouse effect would take over and heat up the planet, potentially making it warm enough for liquid water to exist on its surface.
Source: www.wired.co.uk/article/magnetic-shield-mars-habitable
