Peak Oil News and Message Boards

EnergyUnlimited wrote:Just check how much it cost to bring lunar rock back, even by robotic probe.

NickyBoy wrote:Of course, none of this matters if you have lost the ability to create fuel for your rockets .

Serial_Worrier wrote:A question I'd have for planetary physicists would be how much mass of material can we extract from such bodies before having an adverse effect on the orbits of these bodies? Imagine mining some asteroid, and then suddenly it veers off course and slams into the Earth. Not good.

Another reason we don’t have a manned space program any more is that all those decades of giddy rhetoric about New Worlds For Man never got around to discussing the difference between technical feasibility and economic viability. The promoters of space travel fell into the common trap of believing their own hype, and convinced themselves that orbital factories, mines on the Moon, and the like would surely turn out to be paying propositions. What they forgot, of course, is what I’ve called the biosphere dividend: the vast array of goods and services that the Earth’s natural cycles provide for human beings free of charge, which have to be paid for anywhere else. The best current estimate for the value of that dividend, from a 1997 paper in Science written by a team headed by Richard Constanza, is that it’s something like three times the total value of all goods and services produced by human beings.

As a very rough estimate, in other words, economic activity anywhere in the solar system other than Earth will cost around four times what it costs on Earth, even apart from transportation costs, because the services provided here for free by the biosphere have to be paid for in space or on the solar system’s other worlds. That’s why all the talk about space as a new economic frontier went nowhere; orbital manufacturing was tried—the Skylab program of the 1970s, the Space Shuttle, and the International Space Station in its early days all featured experiments along those lines—and the modest advantages of freefall and ready access to hard vacuum didn’t make enough of a difference to offset the costs. Thus manned space travel, like commercial supersonic aircraft, nuclear power plants, and plenty of other erstwhile waves of the future, turned into a gargantuan white elephant that could only be supported so long as massive and continuing government subsidies were forthcoming.

As a very rough estimate, in other words, economic activity anywhere in the solar system other than Earth will cost around four times what it costs on Earth, even apart from transportation costs, because the services provided here for free by the biosphere have to be paid for in space or on the solar system’s other worlds.

Thus manned space travel, like commercial supersonic aircraft, nuclear power plants, and plenty of other erstwhile waves of the future, turned into a gargantuan white elephant that could only be supported so long as massive and continuing government subsidies were forthcoming.

Sixstrings wrote:
Oh, he's just a luddite.

Elon Musk is making that re-usable rocket, which will cut costs to just the fuel alone which is nothing.

Withnail wrote:the Space Shuttle used to recover and reuse its boosters and obviously the main vehicle, but it didn't make Space Shuttle flights particularly cheap.

It was meant to, in theory.

F9R First Flight Test | 250m
http://www.youtube.com/watch?v=0UjWqQPWmsY

Sixstrings wrote:

Withnail wrote:the Space Shuttle used to recover and reuse its boosters and obviously the main vehicle, but it didn't make Space Shuttle flights particularly cheap.

It was meant to, in theory.

Ya that was the idea.

Let me explain a couple things, here. Firstly, it's not a sure thing SpaceX will successfully develop the reusable rocket. But if they do, then that will be revolutionary.

Here's how it works.

Each rocket stage will separate leaving just enough fuel remaining, to land back on the ground. So, first stage separation goes, and instead of just crashing in the water what it will do is *land itself*, with landing gear legs that come out the bottom and it will make a powered rocket landing.

So the plan is, to do that with all rocket stages.

So the rocket launches, and voila, all the pieces land right back in the same spot they launched from. Stack them back up, fill the fuel up, and it's ready to go again.

Here's a video of a grasshopper landing test. The rocket launches, and then vertically lands itself:

F9R First Flight Test | 250m
http://www.youtube.com/watch?v=0UjWqQPWmsY

KaiserJeep wrote:Never in my wildest dreams would I have thought that anybody would give credence to some weirdo tree-worshiping cultist ideas about space technology.

I mean really - Druids?

Withnail wrote:If having recoverable boosters makes launches cheaper, why were Space Shuttle launches more expensive than rocket launches?

Also how can these boosters keep enough fuel to make a powered landing and still be meaningful boosters?

Surely just a parachute would be more efficient.