Shuttles to the Moon

[freon]

What would it take to adapt or retrofit the shuttles to go to the moon? Would it be that difficult?

[Al Johnston]

Minimum changes would be a lander module to fit in the cargo bay and some means of attaching new external tanks in space: the existing ET is only sufficient to attain Earth Orbit.

This will entail additional hardware to launch the new tank, certainly a new control module, possibly additional boosters and control thrusters.

[PhantomWolf]

It's more that that. Quite simply one of the biggest problems is that the tiles couldn't handle re-entry from a TE orbit. The shuttle wasn't designed to fly to the moon and back and it would take an entire refit and redesign to do it. These are your three major stumbling blocks.

- SME can only fire once, would need redesign to fire multiple times (Launch, TLI, LOI, TEI)
- Fuel load would require another ET to be attatched in orbit with some mechanism to kep the Propellent cold in LO.
- Tiles would have to be redesigned to withstand Earth Re-entry

[nomuse]

"Shuttles to the Moon and maybe Jupiter and Mars,
Maybe someday soon they'll be as plentiful as cars.
Unfortunately, those tiles,
Can not take, the re-entry..."

(Apologies to Bart Howard)

[freon]

What is the difference from a the usual re- entry and a TE re-entry? Is it the speed, angle? I was thinking slow down, redock with the ISS then re-enter. Is that possible?

[grashtel]

freon said:

What is the difference from a the usual re- entry and a TE re-entry? Is it the speed, angle?

Speed, from the Moon you are coming in at about 11km/s from orbit you are coming in at just under 8km/s, and remember that kinetic energy scales with speed squared so while the difference between 8 and 11 doesn't look like much it means dealing with about twice the energy.

I was thinking slow down, redock with the ISS then re-enter. Is that possible?

Not in any practical sense, you would need to use as much fuel as it would take to send your vehicle to the Moon in order to slow down to dock, and unless you can refuel while in Lunar orbit (which has its own nice big set of problems) it means carrying several times as much fuel to the Moon in the first place.

About the only practical way to send a shuttle to the Moon is by recycling it for raw materials to build a vehicle designed with going to the Moon in mind rather than for working exclusively in low orbit.

[echnaton]

What it comes down to is if you want to take something to the moon that is big enough to need the bay of the space shuttle, you might as well build a new rocket to get there. If you want to bring something back from the moon that would require the shuttle bay for reentry, you better build several new rockets because that is a lot of mass to for TEI and reentry and you will need to haul a lot of fuel op there just to get back. As with all things in space travel, the goals of the mission define the craft to accomplish the mission and the limits of the craft limit the goals of the mision. The shuttle is a low earth orbit craft, not a moon ship.

[PhantomWolf]

There is a 5 page thread on this topic on BAUT here

In the end I think that short of a system involving two space stations and shuttles transfering between them, and more between the stations and the Lunar and Earth surfaces, we're never going to have a shuttle service of any sort to the moon.

[freon]

Atlantis just carried up a 17.5 ton load to the ISS. Why not just use one of the LEMs not used during Apollo and take along some extra fuel?

[Nowhere Man]

You still need (a) enough fuel to do a TLI, (b) fuel for LOI, (c) fuel for TEI, and (d) something better than the shuttle tiles for aerobraking.

The shuttle just isn't designed for it.

You might as well ask why penguins don't fly north for the winter.

Fred

[AstroSmurf]

nowhereman said:

You might as well ask why penguins don't fly north for the winter.

Sure they do! See - I have this picture that proves it!

[Nowhere Man]

The reason they don't fly north is because the airlines won't let them take the cymbals on board as carry-on luggage any more.

Fred

[freon]

I was thinking maybe have an engine and tank already in orbit ready to reattach to the shuttle. Attach where the solid rocket booster was attached and use this for the rest of the mission. For the TLI,LOI, and TEI, use it to slow down to around 28,000 km/hr on return to Earth/ then detach the rocket/engine/tank. Re-entery speed would be acceptable for a shuttle landing.

[grashtel]

freon said:

I was thinking maybe have an engine and tank already in orbit ready to reattach to the shuttle. Attach where the solid rocket booster was attached and use this for the rest of the mission. For the TLI,LOI, and TEI, use it to slow down to around 28,000 km/hr on return to Earth/ then detach the rocket/engine/tank. Re-entery speed would be acceptable for a shuttle landing.

The problem is that you need to design the new engine and tank, a launcher for it (which I think would be considerably bigger than a Saturn 5), a way to attach it in orbit, and a way to link it up to the shuttle's systems. By the time you have done that you will have spent at least as much as designing a vehicle specifically intended to go to the Moon rather than using the Shuttle.

Also why do you want to try and use the shuttle for something its never intended to do? It will never work as well as just building something designed for the role.

[Apollo Gnomon]

This subject came up here quite a while back, and one of the more mathematically inclined posters figured out the reentry speed from flying the "brick outhouse" back from the moon. The amount of fuel to decelerate the thing completely negates any benefit of the shuttle being an existant platform. Don't know when that was, but you might try searching for it. Good numbers.