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Showing posts from 2012

Dragon-LP

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Sending humans in a SpaceX Dragon v2 capsule to EML-1 or 2 is a worthwhile possible step in a 100% commercial return to the Moon. The SuperDraco thrusters to be included in the sidewalls of the crew Dragon capsule are more than capable of performing the trans-lunar injection burn, as well as station keeping at the Lagrange point, rendezvous with any preemplaced assets - such as a lander - and returning the crew to Earth.

The total delta-v for such a bare bones mission to EML-2 is a mere 4835 m/s. EML-1 is similar. This is a "quick transit" 4-day trip up to EML-2, so the crew spends less time in the radiation belts. A good estimate of the dry mass of the Dragon v2 is 8000 kg. Using an isp of 320s, the initial mass in LEO is just 37344 kg, or 68% of the maximum payload mass of a Falcon Heavy.

Just going to a Lagrange point with a crew on Dragon would be a momentous achievement and could be done for a mere $150M. However, it is just the first step.

If we fill the remaining Fal…

Human On The Moon Cheapest

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As the first flight of SpaceX's Falcon Heavy in 2014 approaches more information is slowly becoming available. In a recently released NASA study, Wilhite et al revealed an estimate for the mass of the 5.2m wide hammerhead fairing. Combined with the maximum payload to low Earth orbit, it is now apparent that payloads that don't require the fairing could have an initial mass of over 55 tons. This seems sufficient to mount a single person lunar landing (and return) mission with just the one launch.

For simplicity, I will assume a two ton single stage lunar lander with additional drop tanks. I'll use a self-pressurizing mixed monoprop, like NOFBX from Firestar (isp 320s). Starting in LEO the vehicle will perform three burns (3107m/s, 3140m/s, and 2890m/s), not stopping in lunar orbit and dropping tanks after each burn.


Hopefully, SpaceX will kick in some PICA-X for the heat shield, which will be mounted on a Mercury-sized capsule. The lander will look much like the Odyssey/Spa…

Space Advocates Need To Know When To Shut Up!

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NASA recently announced their Gateway station for beyond LEO exploration to the wider press.

This is not news to the space advocate community with articles going back to December of last year. Even so, now is the time when this concept will be received by the politicians as "new". Soon, they will be introduced to the Gateway as either being a part of their plan or something which challenges it.

Many space advocates have complained that the central element of NASA's beyond exploration plan - the Space Launch System - has no payloads, or costs so much that no payloads can possibly be developed to fly on it. The obvious exception to this has been the Orion crew capsule, which is simply seen as too expensive compared to commercial crew offerings. Congress could see the Gateway station as the answer to this criticism.

That would be a good thing - whether you like the Space Launch System or not. The reason is simple: there's nothing else. Up to now, the plan has consisted…

Where did all these suborbital space tourism companies come from??

Were you absent when the suborbital tourism movement was being coined?

Did you miss the philosophy lessons?

Gather 'round young ones, let's sit on the grass and discuss the beliefs that make men build planes when they really want to be building rockets.

Way back in the 70s, the realization that space would never be a frontier until launch costs had been reduced led many to pin their hopes on the Space Transportation System, and later on the only surviving component: the shuttle.

During the 80s, it became obvious that the shuttle would never achieve a reduction in the cost of access to space and, in fact, NASA had stopped claiming that this was the goal of that program.

During the 90s, various rag-tag efforts were made to turn LEO and MEO commsat launch into a massive market which would require the kind of launch capability that only a fully reusable vehicle could service - something like the mythical DC-X that many believed was killed for challenging the Shuttle.

Some say they actua…

Walking Eagle Nomination for the Ad Astra Rocket company

Dear Dr David Livingston and the Space Cynics, I would like to submit a Walking Eagle Award nomination for the Ad Astra Rocket company for their "Human Transportation to Mars" concept.The primary basis of my nomination is the size of the nuclear reactor proposed, but even if such a reactor and all the other support infrastructure to launch the mission from an Earth-Moon Lagrange point was available, and their propulsion technology actually worked, I think there is a very strong argument that such a fast transit decreases mission safety because it eliminates the free-return-trajectory abort mode.The only nuclear reactor the US has ever flown in space is the SNAP-10A, which produced a mere 650 watts of electrical power, from 45 kW of heat. The SP-100 reactor program, which were never flown, was to produce 100 kW of electrical power from 2 MW of heat. The Russians flew reactors which produced 3 kW to 5 kW of electrical power, and built some 40 kW reactors that were never flown…

How Important Is Opening The Frontiers Of Space?

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I have previously written about why space settlement is important, but just how important is it?

In a recent interview Rand Simberg comments:

"What risk you're willing to take is a function of what it's worth to you. In World War II, we sent up squadrons of B-17s over Germany every day - sometimes half of them didn't come back. We tried to minimize the casualties, but we didn't stop flying just because we were having huge losses. What they were doing was important, and we were willing to risk lives to do it."

He was not just referring to the current government efforts at human spaceflight, but also to the growing concern with safety by private spaceflight providers. Just how important is commercial spaceflight?

At a recent hearing of the House Committee on Science, Space, and Technology, Rep E.B. Johnson (D-Texas) answers:

"So far the only potential non-NASA market that NASA has identified for Congress are super-wealthy space tourists, and non-US astronau…

If Copyright Didn't Exist, A Free Market Would Invent It

The philosophical basis of copyright law is a travesty that is not worth going into here. The resultant statist defense of "intellectual property" is heavy handed and infected with cronyism because the philosophical basis is of such poverty. The typical libertarian response is to disavow any right, as such, to protection of intellectual property.

I'd like to suggest this is an extreme response and describe how something akin to copyright is valid in a free market, libertarian society.

The fundamental basis of libertarianism is private property. In this theory there can be no question that the correct and proper owner of work is the creator of that work. (A possible caveat is that all the inputs to the work were already owned by the creator - if you create a sculpture out of my marble, not only is that sculpture mine, I may have recourse against you for using the marble without my permission.) In terms of homesteading, the creator of a work has a greater claim than any s…