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Comment: Hydrogen blimps (Score 1) 200

by buback (#48618687) Attached to: NASA Study Proposes Airships, Cloud Cities For Venus Exploration

I don't see why they would use helium. Hydrogen would be much easier to deal with since it can be readily extracted from the hydrogen sulfide clouds. There wouldn't be any Hindenburg's since there's no oxygen in the atmosphere to react with.

It's also more bouyant, so the gas bag would be smaller for the same weight, and you could launch it from earth with less delta V.

Comment: Re:Is this surprising? Twice as many stars (Score 1) 119

by buback (#47567295) Attached to: The Milky Way Is Much Less Massive Than Previous Thought

So then really what they are confirming is that inference; that matter and dark matter are in a 1/9 ratio, and that if our galaxy has x stars and Andromeda has 2x stars, then Andromeda will also have 2y dark matter mass to our y matter mass.

That seems to be a more interesting finding.

Comment: Cosmic rays (Score 2) 76

Protecting from solar radiation is great, but i understand that the greater threat is cosmic rays. Solar radiation is somewhat easy to block, because you just put a light element shield, like hydrogen tanks, between the astronauts and the sun.

Cosmic rays are much harder to shield from because they are so high energy. They also come from everywhere, so require a omnidirectional shield.

Comment: Re:Extremely expensive (Score 1) 735

by buback (#42289157) Attached to: Solar Panels For Every Home?

As you say, better generators cost more, and the power they generate is significantly more expensive than grid power. You would need to have a lot of power outages and spoiled food in order to break even on the cost during the usable lifetime of the generator.

A $2-3k generator and the cost of instillation is about 30% of the equipment costs of a solar installation, and the equipment is getting cheaper all the time (labor costs are flat or increasing). And a solar installation will pay for itself half way through it's warranted lifetime (about 1/3 of the way through it's usable lifetime).

"Your stupidity, Allen, is simply not up to par." -- Dave Mack (mack@inco.UUCP) "Yours is." -- Allen Gwinn (, in alt.flame