SpaceX for Moon Base

[M.E.T.]

Here's a novel idea for a SpaceX for moon base: bulk buy of F9 launches.

If you want a moon base, build a moon base and stop screwing around with more launch vehicles.

I don't understand the point you are making here. Are you saying a customer who wants to build a moon base could bulk buy F9 launches? If so, (assuming the F9 is capable of serving in this capacity), why is that mutually exclusive with SpaceX designing new launch vehicles in the meantime?

[savuporo]

If you want a moon base, build a moon base and stop screwing around with more launch vehicles.

I don't understand the point you are making here.

The point is that launch vehicles are not, and have not been for a while,  the obstacles for building a moon base. Building more of those is not going to help the case.

[Robotbeat]

If you want a moon base, build a moon base and stop screwing around with more launch vehicles.

I don't understand the point you are making here.

The point is that launch vehicles are not, and have not been for a while,  the obstacles for building a moon base. Building more of those is not going to help the case.

The upper stage of ITSy, which is the hardest part, is also supposed to be a lander. Buying 100 Falcon 9s won't get you any closer to a lunar lander, but building ITSy does.

[sanman]

The upper stage of ITSy, which is the hardest part, is also supposed to be a lander. Buying 100 Falcon 9s won't get you any closer to a lunar lander, but building ITSy does.

Will ITSy be able to handle the Moon? I guess with its large amount of engines, it's just a matter of shutting off more of them as you descend to lunar surface. But it's also meant to do aerobraking, which you don't need for the Moon - altho that might be good for return to Earth.

What would it take to optimize ITSy for the Moon?

[savuporo]

The upper stage of ITSy, which is the hardest part, is also supposed to be a lander. Buying 100 Falcon 9s won't get you any closer to a lunar lander, but building ITSy does.

Having an idea for a theoretical lander doesn't get you much closer to building a lunar base either. In fact, anything shaped as an upper stage is probably going to be a challenge due to payload egress problems.

As it happens, one of the most important features of the Shuttle was it's payload bay, for this certain big space construction project.

What would it take to optimize ITSy for the Moon?

It would have to stop being an upper stage

[Robotbeat]

The upper stage of ITSy, which is the hardest part, is also supposed to be a lander. Buying 100 Falcon 9s won't get you any closer to a lunar lander, but building ITSy does.

Having an idea for a theoretical lander doesn't get you much closer to building a lunar base either. In fact, anything shaped as an upper stage is probably going to be a challenge due to payload egress problems.

As it happens, one of the most important features of the Shuttle was it's payload bay, for this certain big space construction project.

What would it take to optimize ITSy for the Moon?

It would have to stop being an upper stage

The only information we have about ITS says that the upper stage IS A LANDER, not just could be or might be, but IS.

And you have to use a crane. So what? That's needed regardless.

[Robotbeat]

The upper stage of ITSy, which is the hardest part, is also supposed to be a lander. Buying 100 Falcon 9s won't get you any closer to a lunar lander, but building ITSy does.

Will ITSy be able to handle the Moon? I guess with its large amount of engines, it's just a matter of shutting off more of them as you descend to lunar surface. But it's also meant to do aerobraking, which you don't need for the Moon - altho that might be good for return to Earth.

What would it take to optimize ITSy for the Moon?

Yes.

And don't need to optimize it.

[Eer]

Earth-Moon Transportation: We need to turn all this thinking completely around. We need to source propellant and oxidizer totally from lunar materials. Transportation between the lunar surface and LEO should be in a vehicle that departs lunar surface, not LLO, with full tanks, arrives in LEO with enough propellant and oxidizer remaining for the return trip to the lunar surface, again not to LLO. We need to stop thinking of the lunar surface as the destination. It's not. Instead it is the beginning and ending of the journey. LEO is the destination, not the moon. It is a round trip from the moon to LEO and return to the moon. Thought of that way it completely changes the way we think about this. Earth is left completely out of the equation. That's how we need to design the Earth-Moon transportation system. ALWAYS *begin* the trip from the location with the smallest gravity well with completely full tanks. And return there with what's left after destination arrival; pushing less mass because of the expended propellant. Forget about climbing up out of earth's deep gravity well just to get to LEO. Leave that to the taxis.

The delta-v requirements are lunar surface to LEO and back again, begun with full tanks.

And this perspective gives entrepreneurs a business case basis to study how to close, which also creates new sources of funding, expanding the economies of the Earth-Moon system.  Now you have something somewhat similar to gathering beaver pelts as a rationale for a Hudson Bay Company investment in Canada, for example.

[AncientU]

Earth-Moon Transportation: We need to turn all this thinking completely around. We need to source propellant and oxidizer totally from lunar materials. Transportation between the lunar surface and LEO should be in a vehicle that departs lunar surface, not LLO, with full tanks, arrives in LEO with enough propellant and oxidizer remaining for the return trip to the lunar surface, again not to LLO. We need to stop thinking of the lunar surface as the destination. It's not. Instead it is the beginning and ending of the journey. LEO is the destination, not the moon. It is a round trip from the moon to LEO and return to the moon. Thought of that way it completely changes the way we think about this. Earth is left completely out of the equation. That's how we need to design the Earth-Moon transportation system. ALWAYS *begin* the trip from the location with the smallest gravity well with completely full tanks. And return there with what's left after destination arrival; pushing less mass because of the expended propellant. Forget about climbing up out of earth's deep gravity well just to get to LEO. Leave that to the taxis.

The delta-v requirements are lunar surface to LEO and back again, begun with full tanks.

And this perspective gives entrepreneurs a business case basis to study how to close, which also creates new sources of funding, expanding the economies of the Earth-Moon system.  Now you have something somewhat similar to gathering beaver pelts as a rationale for a Hudson Bay Company investment in Canada, for example.

But you still have the sequence backward.  People explored 'the new world' and discovered many valuable commodities -- mostly raw materials or similar as in most undeveloped locations -- and then went about making business cases around them.  Hudson Bay Company didn't invest in Canada trade because they knew beaver pelts would eventually be found and so a 'business case' could close.

We live on a water world... it is equally likely that it will remain cheaper to loft water out of the gravity well than it will be to mine it on the moon.  Certainly it is today and will be for the next many years.  Where the cross-over lies (five years, fifty years, never) is anyone's guess.

[spacenut]

The moon could supply oxygen.  It is in the soil as sand, not just water.  Liquid oxygen is heavy, so liquid methane could be brought from earth to be used in a return trip while filling up with lox on the surface.  This all goes back to L1 or L2 being a staging point.  Have one vehicle to go from moons surface to L1, then a vehicle from LEO to L1 and back.  Then smaller transfer vehicles like a F9 with Dragon II to ferry people from earth to LEO, then dock with LEO to L1 vehicle. 

Specialized vehicles may be cheaper in the long run like this.  In space and a moon lander will not have to deal with atmosphere. 

Moon centric infrastructure can be done in 20 ton increments using F9 only.  ITS or ITSy would be great when it gets going. 

My question of using an ITS moon lander is wouldn't it be over powered for soft landing on the moon if it is supposed to land on Earth.  I know it can be throttled down for Mars, but the moon? 

[rakaydos]

My question of using an ITS moon lander is wouldn't it be over powered for soft landing on the moon if it is supposed to land on Earth.  I know it can be throttled down for Mars, but the moon?

It helps that the moon ITS is carring more fuel when it lands than the mars ITS.  more mass makes up for less gravity.

[groundbound]

The upper stage of ITSy, which is the hardest part, is also supposed to be a lander. Buying 100 Falcon 9s won't get you any closer to a lunar lander, but building ITSy does.

Will ITSy be able to handle the Moon? I guess with its large amount of engines, it's just a matter of shutting off more of them as you descend to lunar surface. But it's also meant to do aerobraking, which you don't need for the Moon - altho that might be good for return to Earth.

What would it take to optimize ITSy for the Moon?

Yes.

And don't need to optimize it.

OTOH, wouldn't a vehicle optimized for LEO to lunar surface operation be extremely different than ITSy? There is a lot of stuff you could leave off, including a lot of the thrust and all of the aerostructure. I wonder if it would actually be a fairly easy new vehicle to design (measured against a lot of stuff that is hard.)

I don't know if this is well thought out, but what I'm asking is that if you do the block F9 buy mentioned above and assume that someone* designs and builds a single vehicle that doesn't exist today it might be cheaper than a lot of the alternatives.

*All we need is to find a spare billionaire laying around not doing anything who wants to get into the space biz but doesn't want to compete with Musk & Bezos.

[Robotbeat]

No, you still need the aero structure to get BACK to LEO or the Earth's surface. The extra thrust reduces gravity losses, so is not a pure loss.

[Asteroza]

Lunar return aerobraking is a thing (PICA-X was designed for it...)

[TrevorMonty]

The problem with using ITS for lunar missions is takes about 4-5 ITS launches per mission.
Using ITS as LEO tanker plus a smaller LV for crew would allow for more frequent trips. Using ACES derived, tankers, crew OTV and lander would allow 6 crew to do round trip from LEO using 100t of LH LOX. Alternatively a single launch of full lander would deliver almost 20t of cargo to surface plus a lander that could be converted to habitat.

Methane lander would do about 14t to surface. A crew mission would be down to 2-3 at guess, havn't done the maths.

[M.E.T.]

The problem with using ITS for lunar missions is takes about 4-5 ITS launches per mission.
Using ITS as LEO tanker plus a smaller LV for crew would allow for more frequent trips. Using ACES derived, tankers, crew OTV and lander would allow 6 crew to do round trip from LEO using 100t of LH LOX. Alternatively a single launch of full lander would deliver almost 20t of cargo to surface plus a lander that could be converted to habitat.

Methane lander would do about 14t to surface. A crew mission would be down to 2-3 at guess, havn't done the maths.

Do the above alternatives allow complete reusability? Or is the "lander that can double as a habitat" a mandatory side effect due to the vehicle's inability to return to Earth?

[gospacex]

My hunch is that when SpaceX talked to people ("tourists") interested in Moon flights, they quickly discovered that there is _vastly_ more interest in going _to_ the Moon, as opposed to going _around_ the Moon.

Having an actual Moon rock which you picked up with your own hands beats the hell out of having a picture of the Moon which you snapped from a capsule flying past it.

[wes_wilson]

My question of using an ITS moon lander is wouldn't it be over powered for soft landing on the moon if it is supposed to land on Earth.  I know it can be throttled down for Mars, but the moon?

It helps that the moon ITS is carring more fuel when it lands than the mars ITS.  more mass makes up for less gravity.

You can add more mass with more fuel or...  You could also transfer cargo from several of them to one of them in orbit and land very heavy with cargo. 

[Robotbeat]

The problem with using ITS for lunar missions is takes about 4-5 ITS launches per mission.
Using ITS as LEO tanker plus a smaller LV for crew would allow for more frequent trips. Using ACES derived, tankers, crew OTV and lander would allow 6 crew to do round trip from LEO using 100t of LH LOX. Alternatively a single launch of full lander would deliver almost 20t of cargo to surface plus a lander that could be converted to habitat.

Methane lander would do about 14t to surface. A crew mission would be down to 2-3 at guess, havn't done the maths.

SpaceX is developing ITSy to replace Falcon 9 and Heavy. So presumably would become cheaper per launch than either.

That makes 4-5 ITSy launches cheaper than using a separely developed smaller lander.

[TrevorMonty]

Even if ITS launches are so cheap, that 4-5 a mission is not problem. Still have crew vehicle waiting in orbit on the refuelling flights, all of which need to successful without significant delays. If ITS only departs LEO with partial fuel load it becomes lot more inefficient as propellant mass fraction goes down.

A separate lunar lander should have higher PMF as there is no heatshield, launch and reentry forces to factor in design.

If ISRU infrastructure is in place to refuel ITS on surface then dedicated more efficient OTVs and landers would exist to service LEO -moon route.

Where ITS will shine is as low cost cargo and tanker  to LEO and maybe EML1.