In this week's comments update, readers are considering a concept for a self-sufficient city on Mars and sharing their views on other top stories.
Abiboo has designed the concept for a self-sufficient city set within a cliff on Mars. The architecture studio claims Nüwa could be built in 2054. 
The vertical settlement, which could eventually house 250,000 people, would be built using materials available on the planet.
"Colonialism is alive and well"
Readers aren't sold on the idea. "Go and live somewhere with no water, oxygen and if you go outside, you die"" asked Bubba10. "Sounds like a marketer's dream."
"The biggest problem is that Mars has much lower gravity than Earth," added Egad. "The human body has evolved to be compatible with gravity and cannot survive without it. Until they can invent gravity, this idea of Mars habitation is merely fanciful fiction." Elie Atallah had other concerns: "Colonialism is alive and well! Settlements! The sense of superiority is staggering."
"Let's not forget that we know a place that is closer, has air, water, food and for a long, long time seemed to be working," finished Marius. "There is new snappy slogan in London: 'Do not move, improve'. How about adopting it on the third rock from the sun""
Are commenters being cynical" Join the discussion ?
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