Reply to post: Re: Speed

No Falcon Way: NASA to stick with SLS, SpaceX more like space ex

Black Betty

Re: Speed

A Holman orbit, is a Holman orbit, is a Holman orbit.

Absent the use of a continuous thrust engine, or a ruinous waste of payload mass, the time to Mars is a fixed quantity. Particularly if you plan on stopping. The whole point of a Holman orbit is to ballistically "kiss" the destination planet's orbit while travelling at very nearly the same velocity as the planet.

And that's the point of the multiple inner system flybys that a number of recent missions used. Each planetary pass is used steal momentum from that planet to expand smaller orbits into larger ones with a minimum expenditure of fuel, until eventually (if everyone did their sums right) the spacecraft creeps up on its destination slowly enough to chuck a u-turn around the planet and throw out the anchors.

It doesn't matter where you're going, if you're means of travel is primarily ballistic, ie. rocketry, then no shortcut will ever get you there any faster than a significant fraction of the orbital period of your destination. The only shenanigans practical or permissible with rockets is to increase total travel time in order to reduce fuel requirements to achievable levels.

Bigger will always let you send more to the destination, but the fuel requirements for faster travel increase exponentially. Only continuous thrust technology can break that impas.

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