New Mars Forums

The idea behind the terraforming is that although we need a lot of resources, energy and time to make it done, when the terraforming will be done, no new resources is needed to sustain the terraforming.
The Earth is in a "eternal" cycle of self recycling. Only energy, our sun, is needed.

And this energy will run out some day. And a lot of time before, the solar system will change to make the life in Earth impossible, if we don't work to change with geoingeniering (perhaps massive, like move planets).

The matter is eternal if we don't transform into energy, so move matter between bodies of the solar system or change the chemical form of this will not exahust the resources.
Terraforming is a great idea but requires that we think like a species, and we works to make a better place in the universe although we and a lot of future generations don't see the results.

Fusions over iron are endothermic. But if we use a mixture of light and heavy atoms, it could be work (for example, use multiple D+D and have some heavy atoms in the same plasma which absorbs some energy to fuse in a endothermic reaction).

But I proposed before something more easy. Transmutate using neutron radiation. Some fusions reactions generate a neutron radiation that could be used to transmutate near elements in the periodic table.
I was talking about to use fusion as neutron radiation, but other options could be feasible. Fision, use natural neutron radiation at very close position to the sun (using a great surface), etc.

We are at the infancy of nuclear energy and technology. It is like talking about big plane engines in the times of the first steam machine.
We don't have net fusion energy yet.

Perhaps the idea of iodine could be changed by bromine (more abundant that iodine) to transmute into krypton.
Is Krypton enough heavy? I'm not sure.

I think that transmutation of elements will became a valuable tool in a medium future where fusion energy will be used at a great scale.

Midoshi was right that with deuterium-deuterium we had to much energy per neutron but I sure that we will make another designs of reactors specially used for massive transmutation of elements.

Terraforming is a slow process in better case.

If we talk about colonization, i think that any subterranean colony is easy to construct that a floating like the propositions for Venus

A subterranean site and enough deep is protected from ratiation and could be    sustained artifially. Light, air, even gravity using artificial pseudogravity with rotation in a cone rotating building (like space torus, but with partial gravity, the geometric form was a cone).

I think the best place for a colony is the moon, because colonization will be maked using controled remote robots and we are at Earth enough near to control robots very similar to real time.

The experience in total autonomous closed colonies could be easily exported to Mars.

But I see Mars the most attractive place to live (with exception of Earth, of course) in medium times, because is the better place to build outer domes colonies where living could be enough comfortable.

Some calculations

We desire a atmosphere pressure like Earth.

Source of units: Wikipedia

Pressure (p) = 101,325 Pascals
Moon surface (s)= 3.793E7 km² = 3.793E13 m²
Moon gravity (a) = 1.622 m/s²

Using gravity as reference of force (is not totally correct as atmosphere has height and not all gases is at the same force)

p=m*a/s
m=p*s/a= 101,325*3.793E13/1.622~=2,37E18 Kg

Wow... It is a lot of mass

My way

First, make a group of robots with replication capability to the asteroid belt.
Make propulsors with fusion energy enough powerfull to move asteroids to go to Venus and put it in orbit.

Make a lot of gas ballons (with helium obtained from fusion energy used to propulsion and the work of robots) to put it in high elevation, where the temperatures are no enought to damage them.

Make so much ballons that covered a lot of the planet. The ballons will be coated with a high reflection material (like aluminium) that should make Venus to reflect a lot of solar light into space.
This should lower the surface temperature. I hope enought to make robots work permanently on the surface (perhaps only on the poles). I hope that
The darkness would not be a problem because the machines used other form of energy (fusion).

The robots would construct on surface factories to make more robots and make carbon absorbers. This machines will release a lot of oxigen. Carbon will be "secuestrated" converting into a solid and stable material, like nanotubes or diamons.
This tecnology is now available, but is very energy intensive. With fusion, this would not be a problem.
An atmosphere with Earth like temperatures and a lot of oxigen, should be  destroy the sulfuric acid.
If not exist enough nitrogen, it could be imported from the moons of Jupiter or Saturn. Another alternative, if advanced fusion was ready, it could be transmutate carbon into nitrogen throught protium-carbon fusion as in stars (far away from current technology, so import is the first alternative).
Oxigen+nitrogen+CO2 extraction+ballons = Cold planet
With enought CO2 removed, some ballons could be removed and return partial light to Venus.

In last place, we could import a lot of water from Kuiper belt.