Why Not Space? [Op-Ed]

[Terralthra]

Maybe people are obssessed with Mars because building a non-shitty habitat on Mars surface is possible (and more importantly, far less expensive despite the distances involved) with our current technology?

I mean, constructing a space station that will house a thousand people and be able to sustain itself with "local" (ie. orbital) resources is immensely more difficult. For one, the modules have to be pressurized like spacecraft, and we're only beginning to understand the issues with long-term habitation of deep space (did you know the ISS has problems with mutated space microbes eating their equipment?)

O'Neill and his grad students designed space stations that would house 10 million people, with rotational "gravity" roughly Terra standard, pressurized to about half the atmospheric pressure of Terra, that could be built with "current technology" in the 1960s and 70s. The problems are logistical, not technological, and as I just pointed out, logistics of getting things from Terra to Mars are worse, not better. Sustainability of a larger habitat is actually much easier than a smaller habitat, as you have enough room for an actual carbon and nitrogen cycle in-hab, and more wiggle room due to the larger volume.

The building materials are silicon and nickel iron (as the main shell is alternating bands of high-tension steel and glass panels), both easily available from NEO asteroids. The inside will have dirt (carbon, iron, silicon - more asteroids), water (comets), and an oxygen/nitrogen atmosphere (comets).

Mars on the other hand has gravity, an atmosphere (a thin one, but still) resources you can get to with surface rovers and can be settled by using what are essentially high-tech tents. It would still require massive amounts of technology compared to settling an actually habitable planet, but less than actual space stations.

I recommend reading The High Frontier (original ideas published in 1974, compiled as a book in 1976, which you can get (paperback used) for a couple bucks). Most of the technological constraints you're referring to are solved problems. The main problem is simply one of construction technique (as these habitats dwarf even the tallest skyscraper), but that's why he designed a series of habitats, Islands I through III, with the smaller ones serving as foundries for the larger ones. Obviously, building these will be nothing like anything we've done before, but the only way to learn the best way to build them is to try.

[Zinegata]

The problem with the O'Neill concept is the enormous cost of shipping materials from the Earth to one of the Lagrange points. We really need to have large scale asteroid mining and water collection technology available before it becomes economical.

[Terralthra]

The problem with the O'Neill concept is the enormous cost of shipping materials from the Earth to one of the Lagrange points. We really need to have large scale asteroid mining and water collection technology available before it becomes economical.

Depending on when one launches and the trajectory taken, getting to/from Terra to the L4/L5 LaGrange points (by way of L2) can take less delta-v than going to Luna, let alone to Mars. See here for some further reading.

[someone_else]

Mars on the other hand has gravity, an atmosphere (a thin one, but still) resources you can get to with surface rovers and can be settled by using what are essentially high-tech tents. It would still require massive amounts of technology compared to settling an actually habitable planet, but less than actual space stations.

In case you didn't notice, Mars's atmo is 0.087 psi versus Earth's at 14.69 psi, and it's composed by 95% of fucking carbon dioxide. So yes, Mars habitats have to be pressurized. And guess what? They have to be bunkers too, to protect humans from harmful particle radiation from solar storms.

Fun fact: even a so pointless atmosphere does its fucking best to annoy humans to no end. Mars dust storms are legendary in size and duration.

The Moon is a much better choice for a Space Bunker. It also makes sense to mine and sell rocket fuel to Earth from it.

The problem with the O'Neill concept is the enormous cost of shipping materials from the Earth to one of the Lagrange points. We really need to have large scale asteroid mining and water collection technology available before it becomes economical.

Moon can supply all that much more easily, although yeah, so huge habs need significant infrastructure in place just to mine enough raw ore to do the job in time.

Depending on when one launches and the trajectory taken, getting to/from Terra to the L4/L5 LaGrange points (by way of L2) can take less delta-v than going to Luna, let alone to Mars. See here for some further reading.

ITN was pretty slow last time I looked at it. Took two years from LEO to moon orbit. For building stuff it's ok, but I doubt it offsets the cost of surface-to-LEO voyages, which would be a real killer.

[HopDavid]

Maybe people are obssessed with Mars because building a non-shitty habitat on Mars surface is possible (and more importantly, far less expensive despite the distances involved) with our current technology?

I mean, constructing a space station that will house a thousand people and be able to sustain itself with "local" (ie. orbital) resources is immensely more difficult. For one, the modules have to be pressurized like spacecraft, and we're only beginning to understand the issues with long-term habitation of deep space (did you know the ISS has problems with mutated space microbes eating their equipment?)

Mars on the other hand has gravity, an atmosphere (a thin one, but still) resources you can get to with surface rovers and can be settled by using what are essentially high-tech tents. It would still require massive amounts of technology compared to settling an actually habitable planet, but less than actual space stations.

Mars atmosphere is a vacuum by earth standards and meager protection against radiation.

Whether a base is on Luna, Mars, or on asteroids, habs will be underground in wholly artificial, pressurized tin cans.

If the goal is more real estate and resources, the asteroids have thousands of times the surface area of Mars. And their shallow gravity wells makes landing and departing much less difficult.

[Terralthra]

Depending on when one launches and the trajectory taken, getting to/from Terra to the L4/L5 LaGrange points (by way of L2) can take less delta-v than going to Luna, let alone to Mars. See here for some further reading.

ITN was pretty slow last time I looked at it. Took two years from LEO to moon orbit. For building stuff it's ok, but I doubt it offsets the cost of surface-to-LEO voyages, which would be a real killer.

There's no question that lifting from Terra to NEO is the first hard part of any space mission, but once you get certain construction tools and thrust capability to LEO, a lot of the materials you need to build up from "small foundry" to "habitat-capable foundry" can be found on Luna or on NEO asteroids, which can be diverted with less thrust. Hell, use tugs with gravitational tethering.

And yes, the ITN is slow, but that's not the hard part. If you get a system set up to move your materials with that transit time taken into account while putting together the construction infrastructure in parallel, then time for the materials to get to the destination isn't as relevant as transit throughput, which is effectively unlimited in space. No one says "supertankers aren't a good way to move oil because I need gasoline NOW, and supertankers take a month to get here from the middle east!"

[HopDavid]

ITN was pretty slow last time I looked at it. Took two years from LEO to moon orbit. For building stuff it's ok, but I doubt it offsets the cost of surface-to-LEO voyages, which would be a real killer.

Correct. The Interplanetary Transport Network does absolutely nothing for getting payloads from earth's surface to LEO. Nor does it help much with getting past LEO. From LEO, at least 3.1 km/s is needed for deep space destinations.

The transportation hubs for ITN are EML1 and EML2.

The moon's volatiles are only 2.5 km/s from EML1 and 2. A ship fully stocked with propellant and life support consumables would have anywhere from a 2.4 km/s to 3 km/s advantage over a comparable ship departing from LEO. ITN is often time consuming, but not always. There is a route from EML2 that only adds 8 days to the journey.

Besides lunar volatiles, many NEOs are quite close to EML1 and 2. Getting back to thread topic, 3 body mechanics is another well known delta V saving method Murphy ignored when calculating his inflated delta Vs. There are asteroids within .2 km/s of EML1 or 2. From EML2, Trans Mars Insertion can be as low as .5 km/s.

[Lord Baal]

I remember a time where a lot of people dreamed into going to space, and firmly believe we'll be living in the moon in short time... now most of the people are engaged only into viewing stupid tv realities shows and updating their facebook to "watching X reality show ZOMG...."