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NASA SLS/Orion/Payloads

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20 minutes ago, tater said:

https://arstechnica.com/science/2019/07/buzz-aldrin-is-looking-forward-not-back-and-he-has-a-plan-to-bring-nasa-along/

I like it. Build Gateway in LEO.

All the parts need the dv to get to the Moon regardless, build/test the stuff at home, less propellant since you don't send Gateway there.

Hmmm, we already have a space station in earth orbit though, we could just use the ISS for any stuff like that. I think that was one of the original ideas for it @_@ werent we going to use it as a staging point for a Mars mission at one point? So whats the point of building another ISS >_<?

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43 minutes ago, Dale Christopher said:

Hmmm, we already have a space station in earth orbit though, we could just use the ISS for any stuff like that. I think that was one of the original ideas for it @_@ werent we going to use it as a staging point for a Mars mission at one point? So whats the point of building another ISS >_<?

One, we don't put it in an orbit designed for Soyuz, we put it in one optimized for the Cape, and for TLI (lower inclination).

Two, Gateway is not designed as ISS, it's designed specifically as a staging area. Think ahead, and include propellant transfer, etc.

Three, it has the PPE, and the tug can always move it to the Moon later if it turns out to work OK.

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52 minutes ago, tater said:

One, we don't put it in an orbit designed for Soyuz, we put it in one optimized for the Cape, and for TLI (lower inclination).

Two, Gateway is not designed as ISS, it's designed specifically as a staging area. Think ahead, and include propellant transfer, etc.

Three, it has the PPE, and the tug can always move it to the Moon later if it turns out to work OK.

I didnt know that about the inclination. Changing inclination of the station would be interesting. I suppose you could send up some light Xenon thruster and push it over weeks to avoid structural stress. I cant imagine too much of an issue using the ISS for staging. Instead of using that dock for commercial stuff like Bigalow you could attach a some module to fill any staging role not within the station's capability. You dont need the PPE if there's nothing to power or propel >_<. 

It's a moot point anyway, Gateway is certainly happening for whatever the reasons, Bridenstine has made that pretty clear and there are probably a lot of contracts signed already. I do like the idea of using the PPE to trial those new ion thrusters. They'll be pretty sweet.

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The moon as a "Mars staging area" makes very little sense. LEO has many advantages over the Moon and very few drawbacks.

pro: lower radiation, can abort to Earth quicker/easier in an emergency, cheaper resupply

con: crowded with many other things in orbit

 

The feeling that the Moon must somehow be closer to Mars is sort of intuitive, but wrong. The delta-V cost of going to the Moon and then to Mars is higher than just going to Mars. The idea of the "gateway" was not really that it made it easier to actually go to Mars. It was just a way of raising the TRL by giving people some experience at an extended stay outside of LEO. However, I'm not sure that's a great idea. With some things, like exposure to radiation, you can't really make it better by practicing it. Instead, it's just better to minimize it.

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Posted (edited)

A LEO Gateway is... not a good idea. I'm not a fan of this "proposal" for a number of reasons.

On a side note, the SLS is a terrible LEO vehicle, but it's a much better BLEO vehicle. It's the reason why, despite having a similar payload-to-LEO as FH, SLS Block 1 absolutely trounces it in payload capacity to TLI. This is a big part of the reason why NASA is gunning for Lunar assembly, the other being that Mars return to the Moon is easier to the Moon, providing it's not a one-way trip. Basically, if you're not diving straight into the Earth's atmosphere on your way back, there are advantages to making a pitstop at the Moon

Edited by jadebenn

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23 minutes ago, jadebenn said:

A LEO Gateway is... not a good idea. I'm not a fan of this "proposal" for a number of reasons.

On a side note, the SLS is a terrible LEO vehicle, but it's a much better BLEO vehicle. It's the reason why, despite having a similar payload-to-LEO as FH, SLS Block 1 absolutely trounces it in payload capacity to TLI. This is a big part of the reason why NASA is gunning for Lunar assembly, the other being that Mars return to the Moon is easier to the Moon, providing it's not a one-way trip. Basically, if you're not diving straight into the Earth's atmosphere on your way back, there are advantages to making a pitstop at the Moon

It indeed is better to TLI. It can only maybe launch 1 time a year, and for the foreseeable future the only payload it can carry to TLI is Orion. Just Orion.

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Posted (edited)
1 minute ago, tater said:

It indeed is better to TLI. It can only maybe launch 1 time a year, and for the foreseeable future the only payload it can carry to TLI is Orion. Just Orion.

Yet nothing else can even carry Orion there. The SLS is unambiguously the most capable vehicle BLEO. That's the entire reason for its existence.

Edited by jadebenn

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They could assemble tug+lander and send that to TLI, then SLS send Orion. Because Orion and SLS are a thing that has to be used. Once other options like NG exists, you send Orion to LEO with that.

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Posted (edited)
1 minute ago, tater said:

They could assemble tug+lander and send that to TLI, then SLS send Orion. Because Orion and SLS are a thing that has to be used. Once other options like NG exists, you send Orion to LEO with that.

And how do you deal with boiloff in the (quite harsh) LEO thermal environment?

Edited by jadebenn

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Just now, jadebenn said:

Yet nothing else can even carry Orion there. The SLS is unambiguously the most capable vehicle BLEO. That's the entire reason for its existence.

When it exists, yeah, it can fly the crappy thing they built (barely) to the Moon in distant orbit.

if Orion had a decent SM, it would basically be all block 1b could fly.

Just now, jadebenn said:

And how do you deal with boiloff in the LEO thermal environment?

You send Orion after the tug takes the rest. It burns icps as planned.

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Just now, tater said:

if Orion had a decent SM, it would basically be all block 1b could fly.

Block 1B is being projected to have 10t-15t of co-manifested payload. You'd still have a significant portion left over after an ESM stretch. Block 1B is just about as capable as the Saturn V, after all.

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3 minutes ago, jadebenn said:

Yet nothing else can even carry Orion there. The SLS is unambiguously the most capable vehicle BLEO. That's the entire reason for its existence.

Does this come down to thrust?

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Posted (edited)
5 minutes ago, tater said:

You send Orion after the tug takes the rest. It burns icps as planned.

So now you need to develop a tug vehicle to carry the whole stack, and a way to refuel the lander or insulate it from boiloff after it's loitered in the LEO thermal environment for several days, which basically rules out a hydrolox lander and lunar ISRU.

2 minutes ago, Dale Christopher said:

Does this come down to thrust?

No, it comes down to the SLS's more efficient upper stage. FH's upper stage is perfectly-suited for LEO, but kerolox's low Isp really bites it in the ass when it comes to orbits further than that.

Edited by jadebenn

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Posted (edited)
2 hours ago, jadebenn said:

Block 1B is being projected to have 10t-15t of co-manifested payload. You'd still have a significant portion left over after an ESM stretch. Block 1B is just about as capable as the Saturn V, after all.

The current SM is at least a km/s short of Apollo's.

The gross mass of the Apollo CSM was ~30 tonnes. That's slightly larger than the mass of the current Orion CSM.

If 1b can TLI current Orion plus 10 tons, it gives the Orion CSM combo about 3000m/s dv if it can have the extra 10 tons of props. A couple hundred higher than Apollo's. With nothing comanifested.

2 hours ago, jadebenn said:

So now you need to develop a tug vehicle to carry the whole stack, and a way to refuel the lander or insulate it from boiloff after it's loitered in the LEO thermal environment for several days, which basically rules out a hydrolox lander and lunar ISRU.

You could, or you could use storable propellants.

They will have to do this with Gateway, anyway, since the trip to the Moon via Gateway takes longer, and requires distributed launches regardless of where Gateway is. Boiloff is a showstopper for Gateway, as well, else hypergolics.

Lunar ISRU is a pipe dream, and can happen after a base is established, but won't happen for a while, it's just not a thing, what's the TRL of lunar ISRU?

 

Edited by tater

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3 minutes ago, tater said:

The current SM is at least a km/s short of Apollo's.

The gross mass of the Apollo CSM was ~30 tonnes. That's slightly larger than the mass of the current Orion CSM.

If 1b can TLI current Orion plus 10 tons, it gives the Orion CSM combo about 3000m/s dv if it can have the extra 10 tons of props. A couple hundred higher than Apollo's. With nothing comanifested.

I can't do the math right now, but the original Apollo SM was sized for Direct Ascent; the contract had been issued before the change to Lunar Orbital Rendevous. So you probably won't need something quite on-par with the Apollo SM, though I suppose it depends on the specifics of the architecture.

I'm fairly certain you're underselling the ESM's capabilities though. What dV figure are you using?

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1 minute ago, jadebenn said:

I'm fairly certain you're underselling the ESM's capabilities though. What dV figure are you using?

1800 m/s.

The Apollo SM was not built for direct ascent, it had higher dv for the CSM because it needed to do the LOI burn for the CSM plus the LEM stack.

ApolloEnergyRequirementsMSC1966.png

 

The total required is ~1900m/s.

Orion cannot do a LOI at LLO and still come home.

It doesn't need much more to be able to make it home, but then whatever lander they send has to be able to get to LLO by itself (which is fine), which simply moves the required propellant to the lander, which then needs even more non-SLS rockets to launch because it must be bigger (Altair style), and there is only the 1 SLS that will ever fly at the same time.

 

 

Note that the Gateway Artemis architecture right now already requires a tug----and the tug has to get to the Gateway in NRHO, then it has to ferry the lander to and from LLO. So they still need a tug that can do LEO-->to LLO (plus and extra several hundred m/s for lunar orbit differences). Then---again, current plan---the lander needs to be able to do a LOI burn at Gateway, then go from LLO--->surface.

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Posted (edited)

Isn't the lander going to be fueled by cryogenics anyway? Might as well put all that fuel in LEO and then go directly to the Moon with some sort of tug. BTW, Aren't conditions around the Moon worse for cryogenics than they are in LEO anyway? How much time (if any) will the station spend in the shade to radiate away all of the heat accumulated on the day side?

The whole thing is obviously proposed to make the SLS seem useful so it's no surprise it's overcomplicated and full of pitstops. I honestly doubt the SLS will fly more than twice.

Edited by Wjolcz

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10 minutes ago, Wjolcz said:

Isn't the lander going to be fueled by cryogenics anyway? Might as well put all that fuel in LEO and then go directly to the Moon with some sort of tug. BTW, Aren't conditions around the Moon worse for cryogenics than they are in LEO anyway? How much time (if any) will the station spend in the shade to radiate away all of the heat accumulated on the day side?

Once in LLO the spacecraft will, as in LEO, spend about half the time in shadow. If you mean in NRHO, then yeah, conditions are far worse (needs a sun shade, really, it needs to be ACES). The trip there, OTOH...

10 minutes ago, Wjolcz said:

The whole thing is obviously proposed to make the SLS seem useful so it's no surprise it's overcomplicated and full of pitstops. I honestly doubt the SLS will fly more than twice.

It'll fly at least twice, unless there is a problem with the green run test, or with Artemis 1 or 2, any of which will be huge setbacks.

Of the combined program, I think that Orion is the better part to keep, as it can be adapted to different LVs.

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2 hours ago, tater said:

It'll fly at least twice, unless there is a problem with the green run test, or with Artemis 1 or 2, any of which will be huge setbacks.

Of the combined program, I think that Orion is the better part to keep, as it can be adapted to different LVs.

Only assuming that other vehicles can haul crews to lunar orbit. 

Tugs are:

  • Unproven for body-to-body transfers
  • never tested to this scale
  • longest crewed tug mission was Gemini 12, which was only docked for 1 day and 19 hours. Not nearly long enough for a lunar mission, and especially not the extended duration missions
  • ACES is the only tug planned right now that could remotely perform this task
  • Hydrolox landers would be impossible to consider due to the 3 day travel to the moon. Systems to keep the fuel frozen would add lots of bulk and electrical equipment to keep the fuel frozen for the trip.
  • Any burns using tugs would put crews in an orientation in Orion that would have any acceleration be negative Gs. So any acceleration would have to be gradual or give the crew a set up where they can turn around in their seats and not get pulled out of their seats.
  • Any vehicle to do this task will need to be tested thoroughly before NASA will consider putting crews remotely near it much less dock with it. The Agena vehicle had been proven before launched for Gemini.
  • ACES is still in development- a certified, flightworthy and trustable article will not be ready until at least 2024 at the soonest. Likely 2025. 

Though you may may not like SLS/Orion/LOP-G approach- it’s certainly the fastest route to the moon. All we need is SLS, Orion, a lander and 2 modules on LOP-G. SLS exists in its entirety and merely needs a few final tests and then assembly for launch. Orion exists and is ready, with the exception of the LSS in the SM. LOP-G is stupidly simple compared to the rest of the systems on the list. It’s a satellite bus with docking ports and xenon thrusters. According to google the average time to design a satellite is 4-7 years. That’s with normal commercial funding- with NASA funding that could be trimmed 2-3 years. Development starting soon after- the docking array should be ready a year or two later. NASA is actively looking for landers right now. With extra funding will speed up development. NASA knows what is needed to land on the moon- what the surface is like- the terrain and so on. Even with the tug to surface plan, a lander is still needed so the time spent is irrelevant. We also don’t know how long ACES can actually function as a tug, though it can reuse the boiled off propellant it can’t use it to power it’s engines- so any burns would have to be done via the onboard thrusters which would be vastly slower and less efficient. So there’s a increase in burn time and a drop in ISP using gaseous fuels. Orion uses hypergols which are more stable. So it can remain in orbit and not lose any efficiency while waiting for the crew during surface stays (possibly up to weeks! In later missions).

As a result, NASA’s current plan may not be “the best”, but it is a fast track to the moon using the tools at NASA’s disposal. Though other vehicle and designs may exist (BFR/Starship, ACES, New Glenn, etc), they aren’t ready for flight yet. SLS is less than a year away from LAUNCH day, not from a major development milestone- from leaving the ground with all of its equipment (minus LSS and that isn’t even NASA’s problem, that’s ESA’s for being slow). Going with other plans like a tug-to-moon concept would actually take longer as none of the tools are ready for flight in NASA’s arsenal- and even if the above vehicles were ready by the end of 2019- they still wouldn’t be considered by NASA for at least another 2-3 years- or after extremely intensive review and tests. NASA dumped a lot of money not just into the contracts to build, plan and assemble the SLS but to also test the SLS using every facility- test stand, and simulation program they have on hand- they have every faith in the vehicle. If NASA is going to choose another vehicle over SLS- it’ll have to beat the SLS in these aspects AND manage to undergo the same tests and still come out proven, safe, reliable and sound. So whether anyone likes it- SLS is here to stay. Likely more than 2 launches as again- NASA isn’t going to be ready and seeing as Musk has again changed Starship AGAIN, clearly it’s in the same developmental cycle jerk that SLS was in 10 years ago. Built alongside Musk-time, the vehicle won’t be remotely ready to replace the SLS by or before 2025, which at a lazy launch cadence of 1 per year starting 2021, that’s still 4 launches of SLS before BFR/SS has flown once. New Glenn has no remote plans to be man rated- so that leaves Vulcan and ACES. ACES won’t fly for a while after Vulcan has its first flight. Though currently in production, Vulcan still likely won’t see its first crewed flights for a while after. But assuming the best conditions- flying crew in 2023 (first flight for Vulcan is slated for 2021- again assuming best case scenario and development is not delayed)- that still leaves room for 2 launches of SLS- and Vulcan unlike SLS- can only throw Orion into LEO- and no further with Vulcan Heavy Centaur. So NASA’s choices are an expensive expendable vehicle that has a mission- funding, and a report card stating that every nut, bolt, sheet of metal, crease, fleck of paint and wire, is safe- vs- a vehicle that’s stuck in a development he’ll similar to SLS in early 2010 (Starship/BFR), a vehicle that currently has no plan to be man rated (New Glenn), and a booster that can’t put Orion anywhere beyond LEO (Vulcan) and it’s little upper stage that won’t even be ready to fly for another 4-5 years, much less be considered by NASA for Artemis for safety concerns. Plus SLS is a political poster child for senators and congressmen who decide how much money NASA gets. SLS gives NASA jobs to hand out and more importantly results. Commercial has rocked the LEO market to pieces. NASA has more developments BLEO than any other entity in the US- not just because they’re older- but because they have the resources, financial and research based, to make big projects like Hubble, New Horizons, Curiosity MSL, upcoming Dragonfly mission to Titan and so on. NASA does not hold any limitation to deep space exploration (ok they do, but that’s more ethical restrictions than authoritative control- see Space Roadster)- but the reason why there aren’t many (if any) commercial probes BLEO is because of cost to develop and the hurdles that imposes. It’s a massive tax on companies since you don’t make money through RnD- the only thing you can gain is investment- and that can only carry you so far. Eventually a final product is needed and that’s where companies fall through (cough Mars One cough), they simply can’t produce and investors know that. Yes SLS is a jobs program- but it’s also a program that’s building the most powerful rocket set to launch within the next four years with a crew onboard. 

NASA is dumb- but NASA knows what it can, and cannot do- and what it does and does not have. It can build a satellite bus and a docking array, bring them together- dock and then send a lander to sit and wait for a crew. Which will transfer to that vehicle and then land, explore the moon and return. Only half of this equation is theoretical- LOP-G and the lander (which is needed no matter the approach). LOP-G being simple to produce and the lander being NASA’s primary interest right now. With any other approach- new technologies will be needed- and new vehicles will have to be tested and developed. This approach minimizes development time to one stupid simple vehicle, and a vehicle that NASA’s gonna need, no matter the approach. 

And before anyone says it- “what about Mars”- Deep Space Exploration vehicle. Using ion thrusters it’ll be able to get to Mars and come back (maybe with a lander years later) with fuel to spare due to its efficiency. So complaining about “less efficient” is a bit of a misnomer when you realize that you’ve got excess in fuel economy to begin with. Plus- LOP-G could act as a great place for the crew to stay at for quarantine. Far away from earth- using our most advanced medical technology- examining the crew for 240,000 miles away rather than landing them on a carrier with hundreds or thousands of others around.

Anyway thanks for coming to my TED Talk. Have a nice day.

Sorry for typos- typed this entire thing on my phone. 

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Posted (edited)
1 hour ago, ZooNamedGames said:

Only assuming that other vehicles can haul crews to lunar orbit. 

The only reason to send Orion to lunar orbit is as make-work for SLS. The new movement towards landing is literally brand new, and Orion/SLS would have been flying to nowhere without it.

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Tugs are:

  • Unproven for body-to-body transfers

A tug is just a stage. It's no different than the Apollo CSM, which was the "tug" for the LEM. Progress is a "tug" that pushes ISS.

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  • never tested to this scale

Meh. It's a thing that docks that has an engine.

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  • longest crewed tug mission was Gemini 12, which was only docked for 1 day and 19 hours. Not nearly long enough for a lunar mission, and especially not the extended duration missions

Progress docks to ISS, then boosts it. Cygnus has as well, right? Those are tugs.

 

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  • ACES is the only tug planned right now that could remotely perform this task

The only one currently thought about that could push something large on TLI? Yeah, except that BO just got a contract to develop a tug.

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  • Hydrolox landers would be impossible to consider due to the 3 day travel to the moon. Systems to keep the fuel frozen would add lots of bulk and electrical equipment to keep the fuel frozen for the trip.

Yeah, they're not a thing except for pretty tightly constrained launches/rendezvous due to boiloff.

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  • Any burns using tugs would put crews in an orientation in Orion that would have any acceleration be negative Gs. So any acceleration would have to be gradual or give the crew a set up where they can turn around in their seats and not get pulled out of their seats.

This is not really a big deal, Apollo CSM was a little over a g I think on LOI, rotating seats should be doable.

 

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  • Any vehicle to do this task will need to be tested thoroughly before NASA will consider putting crews remotely near it much less dock with it. The Agena vehicle had been proven before launched for Gemini.
  • ACES is still in development- a certified, flightworthy and trustable article will not be ready until at least 2024 at the soonest. Likely 2025. 

Funny that the tugs would not be safe for people without loads of flight testing, yet Orion is safe enough literally the first time people ever climb aboard it (and the first time it flies all up).

 

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Though you may may not like SLS/Orion/LOP-G approach- it’s certainly the fastest route to the moon. All we need is SLS, Orion, a lander and 2 modules on LOP-G.

Huh?

We need Orion to Gateway. We'll assume that one.

We need Gateway, which is a couple of commercial launches (PPE plus hab module). The Hab needs a few docking ports.

The lander is large, so it takes at least 2 launches, and presumably gets assembled in LEO first, else each stage of the lander also needs to be a "tug."

The lander either needs to be super, extra large, or there also needs to be a tug sent to Gateway. The tug has to do a LOI burn at Gateway, then have the dv left to move the lander to LLO. The tug might take more than one commercial launch.

Note that any concerns you have about the tug for LEO-LLO equally apply to the Gateway tug. If no tug is possible until 2025, no lander is possible in that timeframe (the lander if anything need more testing than a tug), nor a Gateway tug.

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SLS exists in its entirety and merely needs a few final tests and then assembly for launch. Orion exists and is ready, with the exception of the LSS in the SM. LOP-G is stupidly simple compared to the rest of the systems on the list. It’s a satellite bus with docking ports and xenon thrusters. According to google the average time to design a satellite is 4-7 years. That’s with normal commercial funding- with NASA funding that could be trimmed 2-3 years. Development starting soon after- the docking array should be ready a year or two later. NASA is actively looking for landers right now. With extra funding will speed up development. NASA knows what is needed to land on the moon- what the surface is like- the terrain and so on. Even with the tug to surface plan, a lander is still needed so the time spent is irrelevant. We also don’t know how long ACES can actually function as a tug, though it can reuse the boiled off propellant it can’t use it to power it’s engines- so any burns would have to be done via the onboard thrusters which would be vastly slower and less efficient. So there’s a increase in burn time and a drop in ISP using gaseous fuels. Orion uses hypergols which are more stable. So it can remain in orbit and not lose any efficiency while waiting for the crew during surface stays (possibly up to weeks! In later missions).

Nothing is simple, and nothing goes on schedule, and they have not even started bending metal (unless they use an old ISS module they have sitting around (which they do have)).

Regardless, the craft to get it to Gateway, assemble it, then safe itself doesn't exist, either. That's a stage that can control itself, but with a cargo attached so it can dock the thing, then it disconnects from the cargo (undocks itself?)... what;s that called... it's called a tug. Every single Gateway component after the PPE (which is an ion... tug) involves a tug (unless things like the hab are full spacecraft with RCS, etc, in which case they are... tugs).

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As a result, NASA’s current plan may not be “the best”, but it is a fast track to the moon using the tools at NASA’s disposal. Though other vehicle and designs may exist (BFR/Starship, ACES, New Glenn, etc), they aren’t ready for flight yet. SLS is less than a year away from LAUNCH day, not from a major development milestone- from leaving the ground with all of its equipment (minus LSS and that isn’t even NASA’s problem, that’s ESA’s for being slow).

There is zero chance SLS launches in less than a year. The very end of next year (so 1.5 years ish) is maybe possible. 2 years is more likely. They have no schedule margin, either, for Q4 2020.

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Going with other plans like a tug-to-moon concept would actually take longer as none of the tools are ready for flight in NASA’s arsenal- and even if the above vehicles were ready by the end of 2019- they still wouldn’t be considered by NASA for at least another 2-3 years- or after extremely intensive review and tests.

How do you do the gymnastics to require that a tug stage from LEO needs extensive testing, and will take many years, yet a crew lander will be good to go much faster? Or that the tugs they use to build Gateway would not be the very same sort of thing they would use otherwise as tugs?

If Blue Origin can make a lander in time, they can make a tug in time, and they can make NG in time. So far, they are slower than SpaceX, and since they (BO) are literally the very best chance at a lander right now, that's a lot of eggs in the BO basket, when BO has exactly nothing to show for being in business longer than SpaceX. I like Blue, but they are certainly very... gradatim.

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NASA dumped a lot of money not just into the contracts to build, plan and assemble the SLS but to also test the SLS using every facility- test stand, and simulation program they have on hand- they have every faith in the vehicle. If NASA is going to choose another vehicle over SLS- it’ll have to beat the SLS in these aspects AND manage to undergo the same tests and still come out proven, safe, reliable and sound. So whether anyone likes it- SLS is here to stay. Likely more than 2 launches

Here to stay? Well, it's a jobs program, so yeah. I said as much about the launches, at least 2, probably more.

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as again- NASA isn’t going to be ready and seeing as Musk has again changed Starship AGAIN, clearly it’s in the same developmental cycle jerk that SLS was in 10 years ago. Built alongside Musk-time, the vehicle won’t be remotely ready to replace the SLS by or before 2025, which at a lazy launch cadence of 1 per year starting 2021, that’s still 4 launches of SLS before BFR/SS has flown once.

This will become an interesting thing to watch. SpaceX went from not having launched anything to where they are now in the time SLS/Orion has been worked on (including all the work before the name change that moved over). If you think that SH/SS does fly even once before 2025...

BTW, they change things because they are not wed to sunk cost fallacies. If they see a better way, they are agile, and they change. Pushing forward because that's what you've started is part of why SLS is a mess. The weak SM was the result of Ares. Remember that Orion was supposed to launch to... LEO. In its previous (Ares V) incarnation, the point of SLS (or any Shuttle derived LV) was entirely huge cargo to LEO. Separate crew launch.

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New Glenn has no remote plans to be man rated-

Huh? Blue has said from day one that NG is to be man-rated from the start.

https://www.blueorigin.com/new-glenn/

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Meet New Glenn

Named after pioneering astronaut John Glenn, New Glenn is a single configuration heavy-lift launch vehicle capable of carrying people and payloads routinely to Earth orbit and beyond. Featuring a reusable first stage built for 25 missions, New Glenn will build a road to space.

 

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so that leaves Vulcan and ACES. ACES won’t fly for a while after Vulcan has its first flight. Though currently in production, Vulcan still likely won’t see its first crewed flights for a while after. But assuming the best conditions- flying crew in 2023 (first flight for Vulcan is slated for 2021- again assuming best case scenario and development is not delayed)- that still leaves room for 2 launches of SLS- and Vulcan unlike SLS- can only throw Orion into LEO- and no further with Vulcan Heavy Centaur. So NASA’s choices are an expensive expendable vehicle that has a mission- funding, and a report card stating that every nut, bolt, sheet of metal, crease, fleck of paint and wire, is safe- vs- a vehicle that’s stuck in a development he’ll similar to SLS in early 2010 (Starship/BFR), a vehicle that currently has no plan to be man rated (New Glenn),

Wrong. As I said, NG has always been planned to be man-rated.

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Yes SLS is a jobs program- but it’s also a program that’s building the most powerful rocket set to launch within the next four years with a crew onboard. 

My guess is they fly EM-1 in 2021. Artemis-2 is at best 2022, assume they have literally zero issues with the first flight (they are testing a new heatshield, after all, and they already tested the previous one (EFT-1) and dumped it).

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NASA is dumb- but NASA knows what it can, and cannot do- and what it does and does not have. It can build a satellite bus and a docking array, bring them together- dock and then send a lander to sit and wait for a crew. Which will transfer to that vehicle and then land, explore the moon and return. Only half of this equation is theoretical- LOP-G and the lander (which is needed no matter the approach). LOP-G being simple to produce and the lander being NASA’s primary interest right now. With any other approach- new technologies will be needed- and new vehicles will have to be tested and developed. This approach minimizes development time to one stupid simple vehicle, and a vehicle that NASA’s gonna need, no matter the approach. 

The lander has no real funding yet. If Jeff builds it because he was going to anyway, then they have a shot---and if they end up using it, the long pole will literally have been done by BO, pretty much alone. (woot for them if they do).

All the current NASA talk related to a "soon" lunar landing, BTW has a 3 stage lander. Tug + ascent stage +descent stage.

 

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And before anyone says it- “what about Mars”- Deep Space Exploration vehicle. Using ion thrusters it’ll be able to get to Mars and come back (maybe with a lander years later) with fuel to spare due to its efficiency. So complaining about “less efficient” is a bit of a misnomer when you realize that you’ve got excess in fuel economy to begin with. Plus- LOP-G could act as a great place for the crew to stay at for quarantine. Far away from earth- using our most advanced medical technology- examining the crew for 240,000 miles away rather than landing them on a carrier with hundreds or thousands of others around.

No crew is going to Mars on ion engines. Also, literally nothing needs testing days away from Earth when it could be tested an hour from Earth. Testing in lunar orbit is not a thing, it's an excuse, but not needed, indeed dangerous, and wasteful. Any testing that requires iteration (kind of the point of wringing stuff out, after all, find out how it breaks) is crippled by Gateway, as tests can only happen within the glacial launch cadence, and at huge expense. Testing in LEO means you can swap stuff out quickly, and cheaply.

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Sorry for typos- typed this entire thing on my phone. 

You are truly a masochist! <salute>

Edited by tater

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Also I think people are talking about docking and using tugs, and whether or not it would be safe to use the tug engine if the astronauts were seated eyeballs out. It has happened before, on Apollo 13 I believe, unless all three astronauts managed to cram into the LEM for that burn.

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Also:

 

Gerst leaving could be good for Moon 2024, or... who knows.

Might mean Gateway stops being a thing, actually.

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Posted (edited)
17 minutes ago, tater said:

Might mean Gateway stops being a thing, actually.

Could. OMB's apparently been gunning for it (moreso than they usually gun for human spaceflight programs, that is). That would beg the question of how you'd work around its absence though. We can't do an Apollo-style mission with our current resources.

While the ousting of Gerst was almost certainly a policy thing, we don't yet know what policy thing it was.

Edited by jadebenn

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15 minutes ago, tater said:

Also:

 

Gerst leaving could be good for Moon 2024, or... who knows.

Might mean Gateway stops being a thing, actually.

WOW @_@ thats unfortunate, not that I know much about him but I saw Bridenstine keep referring to him during one of those speeches and he seemed like a pretty important guy. I really don't like the idea of super experienced people at NASA being shown the door... Anyone have any info about the reason? I have a good idea but no point guessing.

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