Your recent series of articles commemorating the Apollo 11 moon landing have been both informative and stimulating. Your sidebar story (Lunar litter: Junk humans left behind, 20 July) does, however, sound a siren warning as to the likely impact of human activity, if and when astronauts resume exploration of the moon and beyond. If 12 astronauts, and their associated support systems, making fleeting visits to the moon 50 years ago, results in nearly 200 tonnes of junk left on the lunar surface, what is the prospect for the environmental stability of other “target destination planets” in our solar system, once national space agencies and commercial exploration companies activate their current development programmes?
We have already made a dire mess of our planet, even though regular human space travel/exploration on a significant scale may yet be decades away, it is not too early for international commitment to binding regulations, perhaps promoted under the auspices of the UN, based on the well-established principles of the polluter pays, and when visiting unexplored territory, take only photographs, leave only footprints.
Without at least some such regulatory framework, the prospect of a space exploration free-for-all in the decades and centuries to come, will only result in a waste mismanagement disaster on a scale that will make the current situation on the moon seem insignificant.
Linlithgow, West Lothian
• Those writing in saying we should fix Earth before attempting to go into space and find other planets are missing the fundamental point (Letters, 22 July). Earth is already broken. The population is at an unsustainable level, and rising to the point where there are not enough sustainable resources to go round, we are destroying this planet’s very fabric just to survive and even if we change our ways now, one day another asteroid will send us the same way as the dinosaurs. We have all our eggs in one very decrepit basket.
We need a second home world, preferably more than one, so that when the inevitable extinction event happens here, the human race will survive elsewhere.
Waun-lwyd, Ebbw Vale
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