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Does it require the same delta-v to reach the same heliocentric orbit that Mars has as it does to reach Mars? Ignoring entering Mars' atmosphere, is the difference only timing of the launch?

meSeeksAndDestroy
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1 Answers1

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Your question hinges on what you mean by "reach Mars". Trans-Mars injection takes you to Mars' orbit, and if your timing is right, takes you close to Mars.

Mars orbit insertion is a separate maneuver, executed close to Mars, which leaves you in orbit around Mars. Without the orbit insertion, you will fly by Mars at about 4800 m/s without stopping. To get into orbit around Mars, you have to do both.

(Besides aerocapture, there's also a trick called ballistic capture which can achieve a very high and barely-stable orbit around your destination without an insertion burn, but it's not useful in itself for planetary exploration.)

Russell Borogove
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  • Belbruno's scheme for Mars ballistic capture calls for a 2 km/s aphelion burn to keep the ship from falling back to a 1 A.U. perihelion. .7 km/s suffices for a loose capture orbit from a standard Earth to Mars Hohmann. Belbruno's ballistic capture is actually more expensive in terms of delta V. – HopDavid Feb 01 '18 at 22:01