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This seems .. incredible. Do we have a different understanding nowadays? (The paper is 20 years old)
This is super out of date. A lot has changed in our understanding of the livability of mars.
Earlier quoted context omitted.
> The potential economic value for space exploration comes from ... mining near earth asteroids for rare and expensive minerals As the article describes, mining asteroids for rare and expensive minerals is more viable from Mars. Earth is in an incredibly deep gravity well: it's remarkable that we made it out with just chemical rockets, an Earth just 1.5x larger in diameter would need a stack of something like 20 Satu…
The article is written assuming colonization is happening (colonization would generate demand) For colonization to happen, there is need for incentive. The article is not giving it. Asteroids near earth provide wast quantities of water and there is cheap energy available (the Sun). Asteroids also have hydrocarbons. Asteroid mining would serve earth. Mining mars would not be competitive source of minerals for Earth. A…
Move them with what fuel?
Also, the Martian missions have been far more ambitious than the asteroid missions.
> Last week, a Nature paper (https://www.nature.com/articles/s41550-018-0529-6) was published by Jakosky and Edwards arguing that, based on data from more recent orbiters, the total near-surface reserves of CO2 are much too low to built up the atmosphere enough for terraforming. What a bummer!
http://caseyexaustralia.blogspot.com/2018/08/atmospheres-and...
He describes some of the back-and-forth dispute, but ultimately comes down pretty pessamistic on Mars terraforming.
Earlier quoted context omitted.
On Earth, you can always airlift people at the earliest sign of trouble, so I don't think the risk is that big. And even semi-serious attempts could give wealth of data useful for actual mission.
Should have phrased this more precise: I meant on Mars every little problem will kill you. On Earth you can rescue people, no problem.
> Assuming complete coverage of the planet with photosynthetic plants, it would take about a millennia to put the 120 mbar of oxygen in Mars' atmosphere needed to support human respiration in the open...Assuming the whole planet is covered with machines converting sunlight to electricity at 30% efficiency, and all this energy is applied to releasing oxygen from metallic oxides...atmosphere could be created in about 3…
Note that converting sunlight to electricity (what the 30% figure is about) is also quite different from using sunlight to convert CO2 to glucose (what the 6% figure is about). Apparently the first stage of photosynthesis effectively does convert sunlight to electricity and does that with 90% efficiency, which is far beyond what our technology can achieve. Source: https://www.economist.com/the-economist-explains/2014…
In the end it depends on the economic incentives, or lack of them. The potential economic value for space exploration comes from satellites orbiting earth (communication, sensors), mining near earth asteroids for rare and expensive minerals and possibly even energy generations. Moon is possible destination because it could serve Earth. From the point of financing the effort Mars is just a sink. First spend hundreds o…
Before people go they should live on a submarine for a couple years to see how they like it.