More News From Mars? Afraid Nasa Funding Could Dry Up?

[Blind groper]

Coober Pedy is actually a very interesting place.

http://www.gluckman.com/CooberPedy.Australia.html

[Jason]

I'm assuming you think that sweaty ball smell is something humans could learn to live with as well?

Assuming I'm assuming correctly in my assumption, what does your house smell like?

[mistermack]

To mistermack

Cosmic rays are not much of a problem if you are on a planet with an atmosphere. Even on Mars, with a thin atmosphere, very little gets through. But if you are in space, like a space city, things are different, and a screen is needed for anyone spending a lot of time there.

Yeh I know. But that screen can be made of any old rubbish. And illuminated to look like a nice blue sky. With a nice artificial sun and a few fluffy clouds.
And solar panels on the sunny side.
It wouldn't even have to be attached to the space station. It could just hang there, in line with the sun, to screen out the sun-generated rays.

So long as you can mine material from the Moon, screening wouldn't be a problem. There's squillions of tons of material available, with little effort needed to lift it off from the Moon.

There are rays from deep space, so you'd still need some screening on the station itself.

[Blind groper]

But that screen can be made of any old rubbish.

That is a bit of an over-simplification. Different materials have different blocking ability. It turns out that water is quite good, and a three metre thickness is sufficient. Other materials would need a lot more. For example, dirt and dust requires more like 9 metres. Since water is actually an essential material, storing it in the outer space city shell at a minimum 3 metre thickness is not a bad solution to the problem.

[mistermack]

The problem varies, depending on what you are trying to do.
If you just want space cities, you can put them in Earth orbit, and not have too much trouble with radiation.
If you want a space station to orbit the Moon, or Mars, you can use plenty of material in shielding.
But if you want to travel to Mars, you can't just load on huge walls for shielding, as you would need to accelerate and decelerate all of the mass. So living in space without getting zapped would be easy enough to achieve, but safe travel is a problem.
By the time that becomes a problem, I would think that they would have developed some magnetic way of deflecting it.

[Gawdzilla Sama]

http://links.email.scientificamerican.c ... &mt=1&rt=0

[Blind groper]

Personally, I think the next major space effort should be a base on Phobos. It makes good sense. Phobos has so little gravity that, instead of expending fuel to land and take off, it is more like a docking maneuvre. It would be easier than a moon trip in terms of fuel and energy, and we know we can do that. The only real difficulty compared to a visit to the moon is the time taken to get there and return.

What would they do there? Send a lander to Mars, and operate it in real time by remote control. The advantages of real time control over the current system are myriad. Far more data can be returned, when a person is available to make moment by moment decisions on actions.

In addition, of course, an established Phobos base is the ideal stepping off point for actual manned Mars expeditions when we are ready for that step.

[Gawdzilla Sama]

Meh, I'd send sections of a space station out via light sail, and collect them at the other end. Then use that instead of Phobos.

[Blind groper]

Gawdzilla

i would go along with that. However, I do have to ask, when is light sail technology going to be that good?

What I would like to see happen, is an interplanetary vehicle built in orbit, with suitable propulsion including light sails if that is practical. Though I suspect that ion drive will be practical earlier. A reusable vehicle that remains in microgravity could carry out numerous trips to Mars orbit, and be refueled when it gets back to Earth orbit.

[Gawdzilla Sama]

Gawdzilla

i would go along with that. However, I do have to ask, when is light sail technology going to be that good?

We have small light sails now. Honeycomb them and you have a "fly eye" sail that will do. If we pushed it we'd have better in 10-15 years.

[Blind groper]

We have small light sails now.

Correct me if I am wrong. But I seem to recall from my reading that every practical attempt to use light sails in space, to date, has failed. Maybe in a few years?

[Gawdzilla Sama]

We have small light sails now.

Correct me if I am wrong. But I seem to recall from my reading that every practical attempt to use light sails in space, to date, has failed. Maybe in a few years?

I remember one being deployed and working.