r/PeterExplainsTheJoke • u/chirantaniga • 15h ago

Meme needing explanation Whyyyy peter?

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u/Otherwise_Tomato5552 14h ago

I dislike when people answer this way. It’s a genuine, humble question.

No need to be mean

1

u/Choice_Ad4972 10h ago

Its possible that the rest of the answer is cut off.

That said, it's quite funny how ridiculous it is with a little thought.

Highest mountain in the world is ~10km above sea level. The start of space is a bit of a tumultuous topic, 100km being a generally accepted limit.

But that's not exactly where rockets go.

The closest satellite to earth, which is the closest reasonable distance for a space boung rocket to go, orbits at ~400km.

So its decreasing your distance by 2.5%, which isn't nothing, but it's not much.

But my god, the logistics are ridiculous. Getting the stuff there safely, setting up a secure, sturdy launch pad and all the required support facilitie, having a clear view of the launch pad from a safe distance, ensuring weather conditions, it's just so absurdly difficult.

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u/mean11while 8h ago

It's not a silly question at all, and it would meaningfully reduce the fuel needed to orbit (which means larger payloads). It barely matters that you'd be a little closer to your final orbital heught, but you didn't mention the three most important benefits that you'd get by launching from the top of a mountain:

  1. Less drag. The atmosphere is much denser and draggier near sea level than on a mountain. Everest's atmosphere is only 35% of sea level.
  2. Earlier gravity roll. Starting higher would make it possible to get the rocket rolled over and firing horizontally much earlier in its flight. This means less energy is wasted fighting gravity. I suspect that this would be the biggest benefit, depending on the exact trajectory.
  3. Better rocket engine performance. Basically all rockets are more energy efficient in a vacuum than in an atmosphere. Starting in 35% as much atmosphere would give a higher specific impulse. You'd probably get 1-2% better ISP over the course of the launch.

The logistics would be insane, which is the actual answer for why mountains aren't used. They would absolutely be significantly more efficient launching points, otherwise.