Entrepreneur Elon Musk is known for wild ideas, and in 2015, he pitched one such approach of dropping a nuclear bomb on Mars. The plan was to kickstart the process of warming the cold planet to make it habitable.
Since then, the idea has caught on with many space enthusiasts, while scientists continue to debate its effectiveness and potential impacts. Last week, Musk rekindled the debate by tweeting "Nuke Mars". The founder of SpaceX, one of the leading private space enterprises, has designed T-shirts promoting the idea.
Why Mars?
Mars has the closest resemblance to Earth in our solar system. So, when humans become capable of interplanetary travel and consider colonising any planet, Mars would automatically be the first target due to its proximity and similarity to Earth.
Scientific evidence suggests that the red planetary did possess habitable conditions in early history up to 3.7 billion years ago. At present, however, the conditions over Mars are too cold due to its distance from the Sun. The effective temperature of the rocky planet is around -58°C—comparable to inland Antarctica.
Habitable conditions in the past were only due to the presence of a much thicker atmosphere that acted as a greenhouse blanket. The Martian atmosphere is nearly 95% carbon dioxide. However, due to continuous loss of gasses to space, the atmosphere has become too thin— about 100 times thinner than Earth's. Therefore, the only way to make the red planet habitable is to ensure enough greenhouse gases in the atmosphere to keep it warm.
If Mars is transformed into a habitable planet, it will be a jackpot, not just for the future of space exploration, but the future of the entire human civilisation. The scientific, economic and cultural implications of such achievement are so enormous that countries and space agencies would leave no stone unturned to make it a reality.
Why nuke our neighbour?
Though it sounds like the plan of a super-villain, (which is what Stephen Colbert called Elon upon hearing his plan), Musk's idea of dropping nuclear bombs on Mars has some logical viability. The entrepreneur wants to 'fix' the planet by nuclear explosions near the poles that could trigger the release of trapped carbon dioxide into the atmosphere and make it habitable.
Scientists, however, disagree. A 2018 study published in Nature, shows that there is not enough carbon dioxide remaining on Mars to provide significant greenhouse warming even if all the trapped gasses are released. Besides, the study says that it would be extremely difficult to mobilise most of the trapped gas and may not be possible with any of the current technologies we possess.
Moreover, the unintended consequences of such an interplanetary mega-weapon operation range from destroying any of the remnant bio-markers on Mars to making it inhabitable for centuries. Also, the possibility that the plan could backfire by causing immense dust to block the incoming sunlight, in turn, cooling the planer and causing a nuclear winter.
Despite all the hurdles, the eccentric billionaire is passionate about making the Mars dream seem possible as he explains in his commentary. Meanwhile, Musk's space company SpaceX is working on a prototype space vehicle named ''Starship'' for interplanetary missions.
Update: Elon Musk has issued a clarification that by 'Nuke Mars' he meant a "continuous stream of very low fallout nuclear fusion explosions". The idea of such pure fusion weapons does offer the possibility of reduced collateral damage due to low fallout. However, despite decades of research, an effective pure nuclear fusion weapons have not been a reality yet.
