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If a rocket flies to any object using a direct ascent it is best for it to reach the needed speed as soon as possible because of the Hohmann effect. When it launches from the ground there is air resistance meaning it is best to have it accelerate slower at the beginning of its flight. The acceleration would probably look something like this enter image description here

What is the best acceleration rate for a direct ascent to the moon?

Links: https://what-if.xkcd.com/24/

The Rocket fan
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    @Antzi that is just for getting into space. If you want to fly to the moon, the results will be different – The Rocket fan Sep 28 '22 at 08:34
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    I don't think it differs – Antzi Sep 28 '22 at 09:01
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    Having a rocket fly up and passing the Karman line is very different compared to a rocket flying so high that it reached the moon on a suborbital trajectory. – The Rocket fan Sep 28 '22 at 09:37
  • I do not think that this question should be closed because it is not a duplicate. The linked question is different and will have different results – The Rocket fan Sep 29 '22 at 05:13
  • I'm not sure what makes you think so ? Because the trajectory will be more upwards than horizontal ? – Antzi Sep 29 '22 at 08:01
  • In any cas, the answer on this question might be generic enough to answer yours too. – Antzi Sep 29 '22 at 08:02
  • what do you mean when you say "optimal?" What are you trying to optimize by varying the acceleration profile? – Erin Anne Sep 30 '22 at 01:23
  • @ErinAnne The way that would use the least amount of fuel possible. If optimal is not the best word for this then maybe you can edit it? – The Rocket fan Sep 30 '22 at 04:35
  • Seems like this might be an even closer dup: https://space.stackexchange.com/questions/20891/is-bypassing-leo-more-efficient-when-launching-to-venus-or-mars . And when you say "hohmann effect" are you talking about https://en.wikipedia.org/wiki/Oberth_effect ? I don't think that would apply during direct accent. – eps Oct 05 '22 at 23:16
  • This might also be of interest: https://space.stackexchange.com/questions/637/do-any-launches-bypass-leo – eps Oct 05 '22 at 23:20
  • @eps yes I do mean that. The spaceship would have to accelerate fast enough while it is still deep in Earth’s gravitational “well”. Since it would be flying upwards the acceleration would have to be faster because it would be flying straight out of the deepest part of Earth’s gravitational “well” – The Rocket fan Oct 06 '22 at 04:31

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