# HELP! D/v to get to a specific orbital altitude (from Earth)

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So there are people expecting me to be smart and calculate D/V...

What is the equation?

The question I was asked is this (paraphrased):

The hubble orbits at 510 km. How much more dV does it take to get up there, than it does for a 400km (ISS) orbit?

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Hohmann Transfer - That has all the math you need, and even works through an example very similar to your question.
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DeltaV is actually relatively simple. It's change in velocity.

Here, you need to know the original orbital velocity, the transfer orbit velocity, and the final orbit velocity.

Then take the difference of the transfer at Periapsis with the original, and transfer at apoapsis with the final.

Add them up and Voila! Total maneuver Delta V.

Knowing the Vis-Viva equation helps, as well as how to find semi major axis, which is pretty easy.

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Oberth effect... there is theoretical dV between orbits and stored dV as fuel (not the same)

And gravity and aerodynamic loses if you ascending from surface...

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Oberth effect

Please, can you elaborate on how this applies to OP's question?

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Please, can you elaborate on how this applies to OP's question?

How much dv it's takes ... formal velocity difference or actual maneuver?

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OP said:

The hubble orbits at 510 km. How much more dV does it take to get up there, than it does for a 400km (ISS) orbit?

What does the oberth effect have to do with the answer to that question?

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