Tag Archives: escape velocity

The Future Of Spaceflight.

Rockets suck. This is a thing that we have established here; they’re terrifically awful ways of getting into space that are only used because nobody has really come up with anything better. There’s all sorts of ideas for wacky drive systems once your spacecraft is actually in space – ion drives, solar sails, Bussard ramjets – but these all sidestep the real problem facing future space travel, which is that you have to get out of the Earth’s gravity well first. This is not easy; even though the Earth is pretty small for a planet it’s still the heaviest of the four terrestrials and has what is to us a very hefty gravitational pull.

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You Have Discovered Rocketry.

Warning: post contains moderately difficult algebra along with hints of calculus. But don’t worry, it’s not that bad.

Rockets are kind of sucky for getting into space. Right now, though, they’re all we’ve got.

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Atmospheres, How Do They Work?

Terraforming’s a bit of a thorny debate these days. Even leaving aside the question of whether or not we should be doing it in the first place — I once gave a talk where I referred to people who thought we should preserve the Martian surface as a sort of natural park as “crazy lunatics1”, only to have one of the other speakers come up to me afterwards and tell me he was one of them2 – there are many technological hurdles to be overcome, ranging all the way from raising/lowering the temperature of an entire planet to a liveable standard to generating a breathable atmosphere. While some of these hurdles are truly significant and will require decades – or even centuries – of technological advance before we can terraform a planet in any meaningful way, there’s also a lot of wilful obfuscation going on about just what is and isn’t possible in the first place. For example, some people will tell you that there’s no point in colonising and terraforming Mars because it’s too small to effectively retain an atmosphere. You should not trust these people, because they are lying – or at least, they are being very economical with the truth.

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