Fixing Mars is No Easy Task

Mars lacks a magnetic shield. That is a big problem for Elon Musk.

No second Earth: turning Mars from a barren desert into a lush forest is far beyond our technological abilities. Image credit: NASA/JPL

What does it take to make a barren, toxic world inhabitable? Those who speak about colonising Mars — Elon Musk, for example — often give the impression that this is little more than an engineering challenge. The reality, unfortunately, is different. Planets are complex, dynamic things, and controlling them is far from trivial.

Take, for example, the lack of a Martian magnetosphere. On Earth this magnetic shield stretches hundreds of miles above the planet and offers crucial protection from the whims of the Sun. Without it the atmosphere would gradually fade away, swept into space by the solar wind. Violent flares would irradiate the surface, destroying the ozone layer and making life all but impossible.

If we ever want to colonise Mars, then, we would need to find a way to construct an artificial magnetic shield. That — like modifying the climate — turns out to be easier said than done; a task that in reality would consume enormous time and resources.

A recent paper, published by researchers in Britain and America, took a serious look at the problem. There are, they think, three possible ways a Martian magnetosphere could be created. Future settlers could try to restart the planet’s core — long dormant — so…