SpaceX for Moon Base

[guckyfan]

Has anyone referenced Elon Musk's old moon comments? Im not sure how to find them, but I remember there were very old comments that a moon base would probably appear before a mars one. I see this not so much as a new direction as something he chose not to talk about for a while.

I only remember a remark or two like We may go to the moon as well, just to demonstrate we can. But most people have interpreted that as Dragon around the moon at the time.

[AncientU]

With all the talk of using lunar resources, what does that mean for hydrolox (if LCROSS turned out to be wrong about the apparent presence of carbon on the Moon), which SpaceX abandoned in favor of methane because of hydrolox's "PITA factor?"

Fuel production should not be as mush of a necessity in Cis-Lunar operations as it is for Mars.  A reusable BFR with routine refueling trips to LEO can also be used do distribute fuel to Lunar vicinity.  ACES white paper described the utility of this approach with only 20 tonne deliveries to LEO, probably assuming a few $1,000k per tonne.  At a fraction of this cost, making fuel on the Lunar surface won't be first order of business.  Water extraction should help support initial outposts, and eventually may be for bulk fuel production.

Habs, power, mobility, communications (broadband everywhere, including things) will be initial infrastructure.  Water maybe next... for consumption; agriculture and fuel production later.

Hopefully initial outposts (plural is important here) will be expeditionary in nature -- from which large regions will be explored and prospected.  Travelers there should be very active and mobile, not just hunker down and stay alive.

[AncientU]

Has anyone referenced Elon Musk's old moon comments? Im not sure how to find them, but I remember there were very old comments that a moon base would probably appear before a mars one. I see this not so much as a new direction as something he chose not to talk about for a while.

I only remember a remark or two like We may go to the moon as well, just to demonstrate we can. But most people have interpreted that as Dragon around the moon at the time.

The old discussion also included 'demonstrating the technology' or some such phraseology... implied landing IIRC.

[octavo]

Water extraction should help support initial outposts, and eventually may be for bulk fuel production.

Are there any good estimates for just how much *easily* extractable water ice there is on the moon?

[su27k]

Has anyone referenced Elon Musk's old moon comments? Im not sure how to find them, but I remember there were very old comments that a moon base would probably appear before a mars one. I see this not so much as a new direction as something he chose not to talk about for a while.

You can search it at shitelonsays.com:

http://shitelonsays.com/transcript/elon-musk-at-mits-aeroastro-centennial-part-2-of-6-2014-10-24

I don't think the Moon is a necessary step, but I think if you've got a rocket and spacecraft capable of going to Mars, you might as well go to the Moon as well - it's along the way. That's like crossing the English Channel, relative to Mars. So, it's like, if you have these ships that could cross the Atlantic, would you cross the English Channel? Probably. It's definitely not necessary, but you'd probably end up having a Moon base just because, like, why not, ya know.

[GORDAP]

Since going to the Moon offers a distinct set of challenges compared to going to Mars, what particular issues will SpaceX most have to get a handle on, and how will they have to adjust their technology development to meet the new mission requirements?

It seems to land significant payload on the moon without surface propellant production they will need a tanker to LLO. So they need to make sure a tanker can survive LLO and earth return.

Otherwise not that much adjustment, I believe. They can land on the moon and drop cargo in a time of the lunar cycle that supports ITS thermal capability as it is. They won't develop any ground infrastructure IMO. They will leave that to others, just be the transport company. Unlike Mars where ITS will have the role of habitat for the first landing.

I know producing methane on the Moon's surface is problematic, but is LOX?  I thought I'd read that LOX should be pretty straightforward using a solar furnace, yes?  If so, that makes me wonder if, since methalox propellants are 75% LOX by mass, would it be feasible to think of a mission/ship profile that land on the surface with enough residual methane in the tanks (but no LOX) for return?  And avoid a LLO tanker?  Does the math work for this?

[TrevorMonty]

Besides water ice, the poles are the only places on the Moon where sunlight is available without interruption. Put up a tall mast and hang the arrays on it like sails, with a motor in the base to rotate the arrays continuously at 1rpM (1 revolution per Month, ha!). In 1/6 g and vacuum, the structure can be very lightweight. A really big array might be a circular arrangement of solar panels on the surface, with a 1rpM 45-degree mirror situated above.

It's probably cheaper, quicker and more reliable (no motors) to simply take up more solar cells. You can lie them on the ground and use local slopes to even things up through the lunar solar day.

A lander with solar panel mast is self deploying and very mass efficient. The motor isn't going wearout at 1 revolution per month. Those individual panels scatter over slopes don't deploy themselves.

[guckyfan]

Refuelling with LOX only would work very well, LOX is most of the propellant mass. You would not have to land the ascent LOX. It requires a different tank size ratio, so a dedicated moon lander. I have seen reports on producing oxygen from SiO2, which is abundant all over the moon and does not require using precious water. Heating it to melting using a solar furnace and then splitting it through electrolysis. Leaves a Si residue which may become useful later. But it is still experimental.

[KelvinZero]

You can search it at shitelonsays.com:

http://shitelonsays.com/transcript/elon-musk-at-mits-aeroastro-centennial-part-2-of-6-2014-10-24

Ok, thanks. That isn't exactly the comment I remembered but very likely I just misremembered it. I couldn't find a better one.

The comment as I remember it was more clear about a moon base before a mars base, but less clear on whether it was SpaceX, government or international. To me the implication was he hoped he could get paid to do moon missions if he provided a very good deal, and this could provide some development costs for Mars.

[DOCinCT]

Has anyone referenced Elon Musk's old moon comments? Im not sure how to find them, but I remember there were very old comments that a moon base would probably appear before a mars one. I see this not so much as a new direction as something he chose not to talk about for a while.

3 years ago at the Dragon 2 reveal Elon said: "Long term we really want to get to the point where there can be thousands of spaceflights a year, and ultimately where we can have a base on the moon and a base on Mars and become a multi-planet species and true space-fairing civilization. So that's where things need to go in the long term."
Updated:
From a Forbes article in April 2012: "He intends to go to Mars. When I asked him if he was g0ing to stop off at the Moon first, he told me that it's not a priority. 'I’m okay with going to the moon, but we've seen that movie before and remakes are never as good. It would be more significant to have a base on the Moon, rather than just going back.' "
I haven't found anything earlier than 2012.

[cppetrie]

Totally in agreement with what he said. Landing just to land is largely pointless. We've done that before. Yes, it could help prove out some tech, etc., but it's still sort of lame from an advancing space flight perspective since it has been done already. Building a permanent base/settlement on the moon, however, is a whole different story. Provides the same development opportunities as landing and more. And it's closer and more accessible for rapid advancement and proving out the tech. The vast majority of the tech for creating permanent habitation of the moon is applicable to Mars. Plus it isn't just a repeat. It's a freaking moon base!! That's a vision of going to the moon I can definitely get behind.

[raketa]

Let me be cynical about it. This is as much about rivalry Elon Musk vs. Jeff Bezos. Elon would not leave that market to Bezos uncontended.

Edit: Elon would not let this push out the Mars plans.

This not about Bezos, but about the affordable path to Mars. SpaceX could have in 5 years BFS that could land on Moon and come back.
Bezos will be lucky to have in 5 years capsule on LEO.
It takes the time to finish it even if you have all money in the world.

[BretShooter]

I think the moon will be a good place to test and possibly build the tunneling machines they will eventually use on Mars.  If they could build it on the moon, they wouldn't have to haul it up the gravity well.  Of course, landing in on Mars would be another challenge!

[dorkmo]

would it be possible to dissasemble the ISS segments and land them one at a time on the moon?

[wannamoonbase]

Refuelling with LOX only would work very well, LOX is most of the propellant mass. You would not have to land the ascent LOX. It requires a different tank size ratio, so a dedicated moon lander. I have seen reports on producing oxygen from SiO2, which is abundant all over the moon and does not require using precious water. Heating it to melting using a solar furnace and then splitting it through electrolysis. Leaves a Si residue which may become useful later. But it is still experimental.

Exactly, LunOx (Lunar Oxygen) would be the first industry on the moon.  Only need decent LOx and then reload ascent on the surface.  The logical step would then be a tanker from the Lunar surface to carry LunOx to LLO.  Then use it to return to earth.  As well it could ultimately become worth shipping LunOx to LEO and refuel for the return trips to the moon or onto Mars.

Why climb out of the Earth's gravity well if you don't need too?

I daydream daily about having the money, or business sense, to set up a prize, lets call it the 'Moon Dirt Prize' to develop Lunar resources technology.  Prizes for demonstrating the technology to start and growing in prize value as you work to flight hardware.  Not just limited to oxygen, there are lots of things to do with silicon, iron and titanium on the surface.  Building habitats and storage tanks with 3D printers, just need the feed stocks.

Using scarce water on the moon for rocket fuel, is very short sighted in my opinion when there is so much oxygen in other forms on the surface.  Need that water for making beer and coffee!!

Eventually launching from the lunar surface would be done with electromagnetic propulsion further leveraging the production of lunar resources.  (And thankfully that is something that some hyperloop folks should have ready for when it's needed.)

[Ictogan]

Exactly, LunOx (Lunar Oxygen) would be the first industry on the moon.  Only need decent LOx and then reload ascent on the surface.  The logical step would then be a tanker from the Lunar surface to carry LunOx to LLO.  Then use it to return to earth.  As well it could ultimately become worth shipping LunOx to LEO and refuel for the return trips to the moon or onto Mars.

Why climb out of the Earth's gravity well if you don't need too?

Because each one way trip between LEO the Lunar surface takes about 5.5km/s of delta-V. When considering that the tanker would need twice that to get from lunar surface to LEO and back to the lunar surface again, this becomes 11km/s - a similar amount to what's needed to get from earth's surface to LEO and back to earth's surface(assuming reentry with a heatshield and propulsive landing).

Delivering earth oxygen to LEO would still be a lot easier.

[AncientU]

Exactly, LunOx (Lunar Oxygen) would be the first industry on the moon.  Only need decent LOx and then reload ascent on the surface.  The logical step would then be a tanker from the Lunar surface to carry LunOx to LLO.  Then use it to return to earth.  As well it could ultimately become worth shipping LunOx to LEO and refuel for the return trips to the moon or onto Mars.

Why climb out of the Earth's gravity well if you don't need too?

Because each one way trip between LEO the Lunar surface takes about 5.5km/s of delta-V. When considering that the tanker would need twice that to get from lunar surface to LEO and back to the lunar surface again, this becomes 11km/s - a similar amount to what's needed to get from earth's surface to LEO and back to earth's surface(assuming reentry with a heatshield and propulsive landing).

Delivering earth oxygen to LEO would still be a lot easier.

The basic delta-v requirements are well defined in the ACES paper... delivering propellant to EML-2 puts it on the gravity well cusp -- ready to depart for interplanetary destinations or drop to the Lunar surface.  Tankers never will travel to Lunar surface (in a sane world that can do the maths*).

* Which I wished I lived in...

[envy887]

Exactly, LunOx (Lunar Oxygen) would be the first industry on the moon.  Only need decent LOx and then reload ascent on the surface.  The logical step would then be a tanker from the Lunar surface to carry LunOx to LLO.  Then use it to return to earth.  As well it could ultimately become worth shipping LunOx to LEO and refuel for the return trips to the moon or onto Mars.

Why climb out of the Earth's gravity well if you don't need too?

Because each one way trip between LEO the Lunar surface takes about 5.5km/s of delta-V. When considering that the tanker would need twice that to get from lunar surface to LEO and back to the lunar surface again, this becomes 11km/s - a similar amount to what's needed to get from earth's surface to LEO and back to earth's surface(assuming reentry with a heatshield and propulsive landing).

Delivering earth oxygen to LEO would still be a lot easier.

The basic delta-v requirements are well defined in the ACES paper... delivering propellant to EML-2 puts it on the gravity well cusp -- ready to depart for interplanetary destinations or drop to the Lunar surface.  Tankers never will travel to Lunar surface (in a sane world that can do the maths*).

* Which I wished I lived in...

Once significant infrastructure exists on the Moon, carrying lunar oxygen from the lunar surface to EML1/2 makes sense. Those points are 15 km/s round trip from Earth and only 5 km/s round trip from the lunar surface. And they are the closest points in Earth's vicinity to other planets and asteroids, delta-v wise.

[mme]

Let me be cynical about it. This is as much about rivalry Elon Musk vs. Jeff Bezos. Elon would not leave that market to Bezos uncontended.

Edit: Elon would not let this push out the Mars plans.

I'm sure Musk and Bezos are super competitive and have huge egos. But I also think both are too smart to let that get in the way their goals which are similar, but different.

I believe Musk will go to the Moon if he believes it supports getting humans to Mars sooner (preferably in his lifetime.)  Whether that support is technical, financial, or political is not important. If Musk perceives the Moon as a diversion, we'll let Bezos have it.

Bezos is more laser focussed on the step by step development of technologies and capabilities and much less on the specific use of the technologies (AFAICT.)

I suspect SpaceX needs the money, not the glory of going to the Moon.

[AncientU]

Exactly, LunOx (Lunar Oxygen) would be the first industry on the moon.  Only need decent LOx and then reload ascent on the surface.  The logical step would then be a tanker from the Lunar surface to carry LunOx to LLO.  Then use it to return to earth.  As well it could ultimately become worth shipping LunOx to LEO and refuel for the return trips to the moon or onto Mars.

Why climb out of the Earth's gravity well if you don't need too?

Because each one way trip between LEO the Lunar surface takes about 5.5km/s of delta-V. When considering that the tanker would need twice that to get from lunar surface to LEO and back to the lunar surface again, this becomes 11km/s - a similar amount to what's needed to get from earth's surface to LEO and back to earth's surface(assuming reentry with a heatshield and propulsive landing).

Delivering earth oxygen to LEO would still be a lot easier.

The basic delta-v requirements are well defined in the ACES paper... delivering propellant to EML-2 puts it on the gravity well cusp -- ready to depart for interplanetary destinations or drop to the Lunar surface.  Tankers never will travel to Lunar surface (in a sane world that can do the maths*).

* Which I wished I lived in...

Once significant infrastructure exists on the Moon, carrying lunar oxygen from the lunar surface to EML1/2 makes sense. Those points are 15 km/s round trip from Earth and only 5 km/s round trip from the lunar surface. And they are the closest points in Earth's vicinity to other planets and asteroids, delta-v wise.

EML-1/2 are only 2.5 km/s from the Moon's surface, 13-14 from Earth, and 0.14 below C3.
A convenient table about half way down article:
https://en.wikipedia.org/wiki/Delta-v_budget

Edit: I just noticed you stated round trip... our numbers match.