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Skylon

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Dang it, I was just pulling up the tab, too. :P

tenor.gif

But yes, frarpin’ LUNAR DRAGON! 5 tonnes of cargo there, but could also return cargo. Wonder what we could do with 5 tonnes of moon rock samples... 

Er, edit, return cargo does not seem to be the case, I squeeeed before I actually read the article. :blush: Tho seems odd that SpaceX would design anything to be disposable from the beginning at this point. Wonder if they might have longer term plans for used modules?

Edited by CatastrophicFailure
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I'm operating under the assumption that the render is accurate, and I'm going to assume they just shove the thing under a fairing. FH with a fairing is a known entity. Easier to throw a vehicle under the fairing and be done with it. Reuse whatever makes sense to reuse (pressure vessel, panels, etc) but otherwise don't worry about shape.

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2 minutes ago, tater said:

I'm operating under the assumption that the render is accurate, and I'm going to assume they just shove the thing under a fairing. FH with a fairing is a known entity. Easier to throw a vehicle under the fairing and be done with it. Reuse whatever makes sense to reuse (pressure vessel, panels, etc) but otherwise don't worry about shape.

It may have a disposable nose cone (Dragon 1 style) and no fairing. 

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So I'm guessing that Dragon XL is either just a boring non-reusable cylinder with a docking port (on the back?) or the render is bland because the final design is still WIP.

I guess that's one way to secure the future of the company if Starship doesn't work.

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1 minute ago, Wjolcz said:

So I'm guessing that Dragon XL is either just a boring non-reusable cylinder with a docking port (on the back?) or the render is bland because the final design is still WIP.

It’s likely the former because the render came from SpaceX. A boring, dirt-cheap non-reusable cylinder. 

2 minutes ago, Wjolcz said:

I guess that's one way to secure the future of the company if Starship doesn't work.

If Starship doesn’t work, SpaceX will keep improving it until it works or they run out of money. It’s required for Mars, and Mars is the reason why SpaceX was created.

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12 minutes ago, sh1pman said:

It’s likely the former because the render came from SpaceX. A boring, dirt-cheap non-reusable cylinder.

So did all the Starship renders and the Red Dragon one (which looked like Dragon 1 but with engines and legs). Oh, and the upper stage landing. Also, that design is kind of odd if we assume that other thing in the picture is the upper stage of F9. Seems like an odd way to do a TLI. I bet it's still WIP. Plans change, especially in SpaceX, it seems.

12 minutes ago, sh1pman said:

If Starship doesn’t work, SpaceX will keep improving it until it works or they run out of money. It’s required for Mars, and Mars is the reason why SpaceX was created.

Really hope it does work soon.

Edited by Wjolcz
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2 hours ago, sh1pman said:

I think it’s pictured right after the TLI burn, decoupling from the upper stage. The docking port seems to be facing back towards the stage.

That's what I find odd about it. Wouldn't a spacecraft require something more efficient than RCS to go to the Moon even after a TLI burn? The engine(s) are obviously not shown, probably because it's still WIP. And if it isn't then I really can't imagine RCS alone bringing that thing back to Earth for reuse.

But then I don't know much about orbital physics. Maybe that highly elliptical polar orbit, which Gateway will occupy, actually allows for low-ish energy insertions and departures. And I don't think that thing will be reusable anyway.

Edit: the fact that the picture only shows the docking port and solar panels makes me all the more certain that these are the only two components guaranteed to be on the spacecraft. The composition of the picture says a lot about what kind of decisions were made when they decided to show it. And it doesn't make sense because they didn't want to show the thing but they wanted to include its destination (the Moon) which is why it's all "mysterious", backwards and featureless.

Edit 2: I know I'm overthinking it and probably overreacting too.

Edited by Wjolcz
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24 minutes ago, Wjolcz said:

That's what I find odd about it. Wouldn't a spacecraft require something more efficient than RCS to go to the Moon even after a TLI burn? The engine(s) are obviously not shown, probably because it's still WIP. And if it isn't then I really can't imagine RCS alone bringing that thing back to Earth for reuse.

But then I don't know much about orbital physics. Maybe that highly elliptical polar orbit, which Gateway will occupy, actually allows for low-ish energy insertions and departures. And I don't think that thing will be reusable anyway.

Edit: the fact that the picture only shows the docking port and solar panels makes me all the more certain that these are the only two components guaranteed to be on the spacecraft. The composition of the picture says a lot about what kind of decisions were made when they decided to show it. And it doesn't make sense because they didn't want to show the thing but they wanted to include its destination (the Moon) which is why it's all "mysterious", backwards and featureless.

Edit 2: I know I'm overthinking it and probably overreacting too.

Falcon Heavy TLI payload is something like 20 tons. Getting to gateway from there is ~500m/s if I recall correctly. RCS thrusters can be fairly efficient enough for this if done right. Draco thrusters (not SuperDraco) have like 300s isp in vacuum. It is my understanding that this will not return to Earth, for re-use or in general, so it doesn't need to do that.

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3 minutes ago, Ultimate Steve said:

Falcon Heavy TLI payload is something like 20 tons. Getting to gateway from there is ~500m/s if I recall correctly. RCS thrusters can be fairly efficient enough for this if done right. Draco thrusters (not SuperDraco) have like 300s isp in vacuum. It is my understanding that this will not return to Earth, for re-use or in general, so it doesn't need to do that.

Ninja’d again. :P

But yes, IIRC the whole point of the near-rectilinear halo mouthful orbit is that it takes very little DV to get into/out of. The gateway’s propulsion module will do the whole thing with only a low-thrust, high-ISP ion drive. It’s not like Apollo, et al, where they need a big burn to brake into LLO. 

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5 minutes ago, Ultimate Steve said:

It is my understanding that this will not return to Earth, for re-use or in general, so it doesn't need to do that.

Where else will it go from the Gateway? Crash into the Moon? IMO it has to return to Earth (and burn up).

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30 minutes ago, sh1pman said:

Where else will it go from the Gateway? Crash into the Moon? IMO it has to return to Earth (and burn up).

Why would it be a requirement to return to Earth and burn up? The moon is a perfectly suitable disposal area as far as I know. Physical contamination with debris may be a minor concern, but we have already crashed tons of stuff into the moon including lunar module ascent stages, Saturn V third stages, that one probe that measured ice or something, etc. And thats just the stuff we've crashed on purpose. Biological contamination isn't a concern as the moon is almost certainly dead, and if it is a concern, the damage has already been done with those bags of astronaut feces.

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6 minutes ago, CatastrophicFailure said:

But 20 tonne lunar lawn darts would be so much cooler. 

A 20t craft smashing into the Moon from high orbit will have ~5.7 GJ of kinetic energy. 135t of TNT equivalent if that energy is released as heat.

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4 minutes ago, sh1pman said:

A 20t craft smashing into the Moon from high orbit will have ~5.7 GJ of kinetic energy. 135t of TNT equivalent if that energy is released as heat.

That won't be a problem until the human residents and tourists are there to start filing complaints.

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5 hours ago, sh1pman said:

Where else will it go from the Gateway? Crash into the Moon? IMO it has to return to Earth (and burn up).

I mean regular lunar impactors would probably be a scientific boon if we can get a seismometer network up on the moon again, and maybe something to monitor the dust

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