To lunar orbit without the LOI Burn?

[Snake]

I was wondering some time ago if it was possible to launch a spacecraft from Earth and do a lunar transfer without needing to do a LOI Burn to be captured by the Moon's gravity and enter a stable orbit around it.

Then I came across this text...

http://discovermagazine.com/1994/sep/gravitysrim419/

What do you guys think?

 

[JamesG]

You can but its a slow trip and you have to get the trajectory and velocities spot on.
What that articile describes in laymanese with all the fuzzy chaos theory stuff stripped away is a eccentric Earth orbit timed to cooincide its apoapsis with a Lunar orbit. As it mentions, you trade speed/fuel ($$$) for time.

 

[TSPenguin]

I think this is highly interesting in combination with a Launch Loop style system.
This trajectory would reduce the complexity, or at least, the mass of supply ships to the moon. Adjusting the trajectory to arrive with the right inclination at the moon would quite cheap.

 

[Urwumpe]

Well, theoretically you could achieve this with a weak stability boundary transfer. Practically, you will still need to do propulsive maneuvers, because the closer you get to the moon, the further you are away from the WSB, and the more you are dealing with mascons and other lunar death traps.

After all: as long as you transfer to equal gravity potentials, it should work easily - when not, you need tidal forces to exchange energy.

 

[JamesG]

Will probably be used for long haul bulk freight, though you will always want to have positive control and propulsion of even "dumb" cargos; and when people start "solar sailing" unpowered around the solar system.