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  On 7/19/2018 at 10:40 PM, Wjolcz said:

There's even illumination of the Moon. I understand solar activity since it could mess with the radio, but moon illumination?

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I'm guessing it's some kind of standard forecast format for more than just launches. Moonlight might not be terribly relevant to a rocket launch, but it could easily matter to other things the military might be doing.

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Edited by kerbiloid
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  On 7/20/2018 at 11:17 AM, Xd the great said:

Huh, aliens.

Anywau, why wont spacex use solid rocket motors on the dragon capsule? They are cheap and powerful...

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Probably because Dragon will have 7 humans onboard, and SRMs aren't the safest of propulsion systems. Yes, hypergolic fuels are still dangerous, but not as dangerous as solids, which are essentially giant fireworks that can't be shut down. Look at the Space Shuttle.

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  On 7/20/2018 at 12:10 PM, RealKerbal3x said:

Probably because Dragon will have 7 humans onboard, and SRMs aren't the safest of propulsion systems. Yes, hypergolic fuels are still dangerous, but not as dangerous as solids, which are essentially giant fireworks that can't be shut down. Look at the Space Shuttle.

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Ahh i see your point...

When will elon ride one of these?

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  On 7/20/2018 at 12:51 PM, Xd the great said:

Ahh i see your point...

When will elon ride one of these?

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When did Von Braun (or any other engineer, or contractor) ride on Mercury, Gemini, or Apollo?

FWIW, Gwynne Shotwell is stocked about point to point rocket travel for herself (to avoid many long flights she takes), and says that's a thing inside 10 years (her timeframe, not Elon's). I'll believe that when I see it, but the willingness to ride is certainly there.

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  On 7/20/2018 at 1:30 PM, tater said:

When did Von Braun (or any other engineer, or contractor) ride on Mercury, Gemini, or Apollo?

FWIW, Gwynne Shotwell is stocked about point to point rocket travel for herself (to avoid many long flights she takes), and says that's a thing inside 10 years (her timeframe, not Elon's). I'll believe that when I see it, but the willingness to ride is certainly there.

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This is a person who sent his personal car into orbit around the Sun. I bet a test pilot will be himself, to demonstrate safety of his rockets.

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  On 7/20/2018 at 12:56 PM, RealKerbal3x said:

Who knows? Maybe when they've got the BFR Mars transportation architecture up and running he'll automatically get a ticket. Elon once said: 'I would like to die on Mars, just not on impact.' :D

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I think he'll fly to orbit, and maybe even make a visit to the Moon if things are really going well, but he's probably most needed on Earth until Mars colonization is well underway, and that's where he'll be until then.

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  On 7/20/2018 at 11:17 AM, Xd the great said:

Huh, aliens.

Anywau, why wont spacex use solid rocket motors on the dragon capsule? They are cheap and powerful...

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And not remotely throttleable or reusable. Or a technology SpaceX has any experience with whatsoever. They've made a point of using no solids at all on everything they've built, down to using non-pyrotechnic separation mechanisms. It's unlikely that they'd start now, especially when there exists an alternative.

Also, you have to remember that SpaceX were planning to propulsively land Dragon V2, which would have required deep-throttling liquid engines, such as SuperDraco.

Oh, and they aren't really cheap either, not at the kinds of prices SpaceX can built liquids at. Solid booster manufacture is not as trivial a process as some people may make it out to be. I will grant you the powerful part, though with the kinds of thrust-to-weight ratios SpaceX can achieve that qualification becomes increasingly insignificant.

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Fuel wise, Solids are actually pretty darn expensive. It's only the fact that the "engine" consists of a nozzle and a reinforced fuel tank as the combustion chamber that makes them cheaper than liquid fuel engines. Once you can return the expensive liquid engine safely to earth, refueling it is relatively cheap. (refurbishment is another matter, but can be solved in the design phase)

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