SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/cap-orbit-needs-sideways-speed

Reaching orbit takes altitude and what else?

Horizontal velocity, or sideways speed.

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  1. Cold temperatures
  2. Horizontal velocity ✔
  3. Thin wings

Why: Going high is not enough to orbit. A spacecraft must also move sideways fast enough that it keeps falling around the Earth instead of down to it.

Huh, didn't know that: NASA notes that Spaceship One reached space but did not reach orbit.

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How do you know when the moon has had enough to eat? When it's full.
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References

Answer: Horizontal velocity. Going high is not enough to orbit. A spacecraft must also move sideways fast enough that it keeps falling around the Earth instead of down to it.

  1. NASA Glenn: Flight to Orbit www1.grc.nasa.gov/beginners-guide-to-aeronautics/flight-to-orbit
    orbital flight is a combination of altitude and horizontal velocity
    Checked 2026-10-10.

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