Science Forums 2

[CraigD]

Originally Posted by LaurieAG

If you could drop a couple of large icy Kuiper belt objects on its surface you may just have a chance of making Mars habitable. Getting this same large amount of water from Mars itself would be a huge problem.

Originally Posted by Thunderbird

It would need to start with some astrophysical engineering. But even if you could somehow move these objects; Billions of tons across 100s of millions of miles, it would still take Billions of years for the planet to reform itself.

Originally Posted by CraigD

I don’t think this is true.

The various “watering/atmosphere-thickening” plans involving colliding KBOs (comets) with Mars don’t involve impacts that would damage Mars so much that it would need to “reform”, nor do they propose to duplicate the natural evolution of a biosphere. They simply propose to – quickly, within decades and centuries, not thousands and millions of years - add water and gas to create more human-friendly surface conditions.

Originally Posted by Thunderbird

I don't think this will ever be enough, You cannot just add water and gas and expect to initiate the dynamics of a cyclical ecosphere upon a static undersize dead rock.
You would need to add enough mass initiate a cataclysmic planetary melt down, and reboot the entire system, and start from scratch.

“Making Mars habitable” and having “the dynamics of a cyclical ecosphere” are different requirements.

Conventionally, terraforming refers to making a moon or planet similar enough to Earth that it’s habitable by humans, not recreating an ecosystem of similar power and complexity to Earth’s.

Originally Posted by LaurieAG

By adding a moon you could possibly drag Mars, kicking and screaming, back to life (or at least try to regenerate its dynamo in a 'soft' reboot).

Given that an ionosphere, which Mars currently has, even with its thin (about 0.01 Earth’s pressure) atmosphere, provides most of the habitability benefits that a magnetic field contributes to, why would you want to spend effort to give it a magnetic field?

In short, I remain of the opinion that, while with much greater space engineering capabilities than are currently available to humankind, terraforming Mars is technically possible, I doubt it will be economically or esthetically attractive at any time in the next 100 years.