All the Arguments for Space Exploration Ever- Part 8
How many people can the Earth support? As it turns out, the resources on Earth are indeed limited. In the book ‘The future of life’, Edward O Wilson gives an estimate — “If everyone agrees to become vegetarian, leaving little or nothing for livestock, the present 1.4 billion hectares of arable land would support about 10 billion people.” But since this unlikely that everyone will switch to the vegetarian diet anytime soon and the fact that eating livestock is inefficient in terms of conservation of the overall food produce, we may be looking at an alarming future scenario. It can be imagined that the most non-violent option to permanently tackle this impending problem would be human space inhabitation.
In the future, there are a host of risks like molecular nanotech weapons, wars, super-intelligent artificial intelligence, nuclear terrorism and engineered pandemics that have the capacity to cause human extinction. On top of all of that threat is a major philosophical dilemma, whether our moral obligations to future humans outweigh those we have to humans that are alive and suffering right now. Philosopher Toby Ord mentions, ‘ I am finding it increasingly plausible that existential risk is the biggest moral issue in the world.’
A global catastrophic risk is a hypothetical future event that has the potential to damage human well-being on a global scale. Some events could cripple or destroy modern civilisation. Any event that could cause human extinction is also known as an existential risk.
In 2008, a small but illustrious group of experts on different global catastrophic risks at the Global Catastrophic Risk Conference at the University of Oxford suggested a 19% chance of human extinction over the next century.
Human space exploration and settlement is one great risk mitigation strategy. This way, we can isolate the impacts of a life-threatening event on the Earth from a settlement far away in deep-space.
An impact by a 10 km asteroid on the Earth has historically caused an extinction-level event due to catastrophic damage to the biosphere. The impact speed of a long-period comet would likely be several times greater than that of near-Earth asteroid, making its impact much more destructive.
Generally, the warning time is likely to be only a few months. As per Michael A Hearn, principle investigator of the NASA Deep Impact Mission that impacted a comet with a space probe, even if we had a plan, it would take one year to launch. And you would have to have something ready to launch, basically, if you wanted to do something on short notice. This should be alarm enough for the need to draw up official, globally accepted plans to tackle a threat like an asteroid impact.
In order to avoid collision with such impactors, we could go for destructive or deflective solutions like gravity tractors (spacecraft which pull out of impact trajectories- asteroids/comets with their own gravity field) or nuclear explosive device exploded over surfaces of a threatening impactor.
Any one of these solutions would require a coordinated effort from global space agencies and militaries. Hence, investment needs to be put into development of such space programs.
Also read other parts of the series: