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Rocket Launch in New Zealand Brings Quick, Cheap Space Access

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Re: Rocket Launch in New Zealand Brings Quick, Cheap Space Access

#201

Earlier quoted context omitted.

> Russian rockets use some nasty stuff Do you have a source for that? What sort of "stuff"?

I'm guessing they're referring to the hypergolic propellants used on the Proton rocket? Which are, indeed, notoriously toxic. In which case, they're not something SpaceX has shyed away from; they are indeed not used on the Falcon, but hypergols will power the SuperDraco engines on the Dragon 2. When you need storable propellants (either for a launch escape system that needs to be ready to go at any time, or for ICBMs…

> When you need storable propellants (either for a launch escape system that needs to be ready to go at any time, or for ICBMs that can be kept in a launch-ready state), and a solid rocket won't do for whatever reason, there's just nothing else that will do the job.

That is, if you don't count Soyuz landing capsule, which carries about 30 kg of hydrogen peroxide and keeps that for up to 210 days flight before landing. And if you don't count Zarya spacecraft, which - never built, but was designed to use hydrogen peroxide for powered landing ( https://en.wikipedia.org/wiki/Zarya_(spacecraft) ), also after long flights. And Buran spaceplane, which used LOX and kerosine for maneuver engines able to word in a month-long flight. And Kliper spacecraft designs with propulsion on LOX and ethanol.

Even hydrogen can be made working after weeks of flight if you have large enough tanks - there was design of upper stage of N-1 with that. With Lockheed works on space tanker ( https://en.wikipedia.org/wiki/Advanced_Cryogenic_Evolved_Sta... ) the time range can be extended even more. I think we can leave those toxic propellants aside when we want.

Re: Rocket Launch in New Zealand Brings Quick, Cheap Space Access

#202

Earlier quoted context omitted.

> Russian rockets use some nasty stuff Do you have a source for that? What sort of "stuff"?

>Do you have a source for that? What sort of "stuff"? Russians are still using hypergolic fuels rather than the methane/oxygen that most new generation launch vehicles are using.

Those methane-based launchers all have not yet left the design stage.

Re: Rocket Launch in New Zealand Brings Quick, Cheap Space Access

#203

Earlier quoted context omitted.

Electric turbopumps are an answer to the question: "how small can you make a commercially viable orbital rocket?" Atmospheric drag effects rocket performance less and less the larger a rocket gets (square-cube law), so that a rocket like the Space Shuttle can effectively ignore the atmosphere. Conversely, the smaller a rocket gets, the harder and harder launch gets. This is the problem Rocket Lab has decided to attac…

A variation of a couple of degrees during launch would rip the Shuttle's wings off, so "ignore" is not the right word here.

Don't forget the complete lack of a launch escape system...
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