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I don't think either of us know much about this, but I do know that docking with the ISS to unload supplies requires completely different equipment than doing a rendezvous between a lunar lander and a lunar orbiter for Earth return. (That's why I didn't say merely "docking".)

The only craft SpaceX has that can land on Earth or the Moon is Dragon. I am pretty sure Dragon does not have enough delta-v to do a full propulsive landing on the moon (no aerobraking available) and then return to orbit. And they definitely don't have the tech to re-fuel in lunar orbit for the return to Earth. None of this equipment exists.

Not to mention that this would be a totally new lunar strategy, since the Apollo mission returned to earth in the lunar orbiter (Command Module) rather than re-fueling and returning in the lunar lander.




> I am pretty sure Dragon does not have enough delta-v to do a full propulsive landing on the moon.

The information I'm finding on the internet suggests Dragon 2 should run around 400 m/s of delta-V (it only needs on the order of 200 m/s to go from terminal velocity aerobraking to landed on Earth).

TLI to LLO is 800 m/s, and I'd guess that a Circumlunar return trajectory to LLO transfer would be on that order -- which is already out of the Dragon 2's range and you're only trying to get into orbit on the Moon, not return, and definitely not land or take off again.

Its close enough though that a beefed up Dragon 3 might be able to dock with some kind of space station and refueling dock in lunar orbit, then you just need to have a lunar ferry (Apollo sorta downsized all of this and crammed it all on top of a Saturn V for one-time use -- I'm thinking a bit bigger for the whole system and more cough reusable...)


Yea, I am not a rocket guy.

However, the minimum delta V to land on the moon is ~1.72 km/s, and you need another 1.72 km/s to get back into orbit + some safety factor ~2.2-2.4 km/s. By comparison it takes ~8km/s to get from LEO to low moon orbit and back to earth. Though you can reduce this by how hard to hit the earth's atmosphere. So, having fuel to land and take off from the moon is not that much worse than getting to the moon and back.


> By comparison it takes ~8km/s to get from Earth LEO to Moon LEO

No, from Earth LEO some 3.1 km/s will get you to TLO, and then some ~1 km/s will take you to Moon low orbit, so total about 4(+) km/s. 8 km/s is an approximate budget for a round-trip between low orbits.


Sorry, butchered that. I was trying to say the figures are less exact depending on how hard you want to hit the earths upper atmosphere. ~8.2km/s if you want to end up in earth LEO ~8km/s if you want to get back to the earth. You can also save a little if your sending an unmanned craft and don't care how long it takes or skip low moon orbit.


I wonder if spaceX is going to send a permanent colony of bots on moon to make a base there. The latency is a lot lower than Mars and would make a good start.

Sending a couple of humans around moon for tourism is a waste of resources.


Sending a couple of humans around the moon for tourism is a great R&D opportunity, paid for by someone else's money.

See: Apollo 8 mission.


They have paying customers. When you're in business to make money, you do what you can bill for.

Though I don't know why anyone would want to spend a week locked in a tiny can like that, let alone pay big bucks for it. There's a limit to the discomfort I'd be willing to endure for bragging rights.


They're said they have no particular interest in going to the Moon as it wouldn't teach them anything useful about going to or living on Mars and would just be a distraction. Of course if someone else wants to contract them to do so and they can make a buck off it, that might be different.


The Moon is a terrible "start" for Mars. They are very different places, and require solving very different problems. In many ways, Mars is a lot easier (the atmosphere can do a lot of the work of slowing you down, you have the raw materials to make methane (the rocket fuel SpaceX will be using), etc).

People tend to think of the Moon as a "staging point" on the way to Mars, but in reality, it would be a significant detour.


> Sending a couple of humans around moon for tourism is a waste of resources.

One persons waste of resources is another persons revenue. They're not doing it for charity.


So is it possible for them to launch multiple vehicles into Earth LEO, rendezvous with one another and then transfer to Moon LEO?




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