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How about putting the crew acceleration couches in a sealed crash and fire resistant compartment near the top of Starship (also acting as the storm shelter) and arranging the support structure for the decks underneath or at least the central part of them in such a way that they would provide deceleration over the whole length of Starship as the crew compartment is forced down through the ship on impact. The central cylindrical corridor could be designed with four or eight weak points running down its length to split apart. that would provide a considerable crush zone even if the landing were at an angle. It might even be possible to arrange an emergency vent of oxygen from the header tank to ensure it was as upright as possible before impact in case of total engine failure.

But I don't think they are going to do that. Probably because it would involve a vast amount of testing and design work which would hardly ever be use and even when it was need might not always work.

I like it.  But I think testing is not a big deal.  It's all drop-from-crane testing and the car industry does this all the time.
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Expect the eventual fallout from all of SpaceX's experimentation with reflectivity and effects to terrestrial observation assets to result in an eventual US and then later an International set of standards for all new sats in Earth orbit. This will be a big gain for the terrestrial astronomical instruments usage. But for even more advanced observations will likely move out into space beyond most of the objects that are in the way such as placed out at Lagrange  Earth-Sun 2 past the Moon's orbit and is permanently facing away from the sun. This is beyond the Lagrange Earth-Moon 2 point.
Most observations can't and won't move out into space. The cost of a space based observatory is HUGE compared to an equivalent ground based one. And just for the record, launch cost has no impact on this. Free launch won't change this.

My bold.

Do you have links to actual numbers I can do research on?  Published reports, etc.  Also interested in $/minute of actual observation time for different types and locations of terrestrial observatories.  Thx.

Since this is not really Starlink specific, a PM is probably more appropriate.


Look up the price of literally ANY space telescope. Also, the price is as much time as it is money.  Look into the years and years of time it takes to build and design one. This is a silly fantasy that free launch matters is the majority of the solution.

However, to save you the 3 seconds of google time, the ELT (biggest telescope EVER https://en.wikipedia.org/wiki/Extremely_Large_Telescope) has a price tag of 1.5 billion euros. We literally do not have the technology to build this in space, but if we tried, after the tech dev and decades of work, it would easily be 50billion plus. How does the difference of $30million on the launch price change anything?

 Even if there was free launch today, it would easily be a decade to fund, design, build, and test something to take advantage of it.

I was actually asking about the development, construction and operation costs of terrestrial observatories as a baseline.  No reply necessary.  I'll find that info myself.

Now back to discussions directly related to Starlink...
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Waypoint 1 is reached; waypoint 2 in about 8 mins
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How about putting the crew acceleration couches in a sealed crash and fire resistant compartment near the top of Starship (also acting as the storm shelter) and arranging the support structure for the decks underneath or at least the central part of them in such a way that they would provide deceleration over the whole length of Starship as the crew compartment is forced down through the ship on impact. The central cylindrical corridor could be designed with four or eight weak points running down its length to split apart. that would provide a considerable crush zone even if the landing were at an angle. It might even be possible to arrange an emergency vent of oxygen from the header tank to ensure it was as upright as possible before impact in case of total engine failure.

But I don't think they are going to do that. Probably because it would involve a vast amount of testing and design work which would hardly ever be use and even when it was need might not always work.
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I have been impressed with what China has done recently. But note that this is a pretty big step for them. Solar panels at Jupiter have some distinct engineering challenges. And the Uranus flyby spacecraft would require RTGs, and China has not flown them yet. So that's two technologies that they need to perfect.

And yes, they have certainly mined every bit of open source engineering data they can get on those subjects from NASA, and have probably obtained restricted data as well. But copying is not the same as learning how to do it.
The stolen info will certainly help them along. The hacked curiosity landing data obviously made a difference for landing on mars.
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2 mins from Waypoint 1, Dragon will continue on to Waypoint 2
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There are sharply diminishing returns to adding more propellant. . . . Instead of just blindly throwing prop at Starship, you need to ask what you're trying to achieve.  When you narrow it down to a variety of round-trip cislunar missions and one-way Mars missions, I haven't found a case where stretching the tanks past 1500t helps (although that extra 300t helps a lot, just because of how the delta-v budget to and from cislunar works out), nor have I found any cases where pusher/depot, tandem burns, or even drop tanks help very much.
I find myself thinking that a special cargo "tug" with a solar-powered (or nuclear) ion drive that slowly chugs from LEO to (say) NRHO would be worth it at some point. Yeah, it's slow and not very energy-efficient, but if it could move a full depot in (say) a month or two, that'd probably be well worth it at some point, since, with specific impulse of ~5000s it wouldn't need to be refueled very often.

This isn't going to happen any time soon.  For it to make any sense at all, the cadence would have to be high enough to warrant a major development effort to produce such a huge SEP tug.  And if the cadence is high, then you'll have a whole bunch of fleet costs with a whole bunch of tugs in transit.  Those fleet costs will likely swamp the cost of adding a few additional (again, high-cadence) lift tanker launches to move prop to cislunar via brute force.

Maybe to focus the discussion a bit, I think there are three¹ major milestones in the use of tankers to handle cislunar operations:

1) Refueling for the Option A and B LSS.  This is important because it's the key to Artemis's continued existence.

2) Refueling for an LSS staged with crew out of LEO, and returning propulsively to LEO, with an F9/D2 or Starliner bringing the crew to/from LEO.  This is important because it does away with the use of SLS/Orion and therefore reduces the cost per mission by $2B-$3B, even before Starship is crew-certified for launch and EDL.

3) Refueling for a not-quite-vanilla Starship, which is capable of landing on the Moon and returning directly to EDL on Earth.  This is almost certainly SpaceX's endgame, but it requires that all-important crew-certification of launch and EDL.

Finding the proper conops for each of these requires balancing:

- Operational complexity
- Risk of refueling and extra RPODs
- The fact that refueling risk is reduced over time
- Tolerance of risk for crewed refueling operations
- Tolerance of risk for uncrewed operations involving spacecraft that will later be crewed (and are therefore expensive)
- Tolerance of risk for dumb tankers and depots
- And finally the cost (mostly in lift tanker launches) of the various conops. 

It is, to put it mildly, a rich trade space.

After fooling with these for a while, I think you need to follow these guidelines:

1) Option A and B missions have to be as simple as possible, and the LSS itself can't be refueled more than once per mission, nor can it be refueled with crew on board.

2) Staging LSS from LEO for eventual propulsive return requires two refuelings per mission (one in LEO and one... somewhere else).  The second refueling has two problems:
a) The crew is on board (unless you do weird stuff using the Gateway).
b) The refueling has to occur post-lunar-ascent, which makes abort contingency planning very dicey.  (There is an option to do pre-descent refueling, but the number of lift tankers needed almost doubles.  Carrying the prop to return to LEO down to the lunar surface and back is expensive.)

3) When crews are able to be launched and landed via Starship, there are two crewed refuelings instead of one (one in LEO, one at some higher energy), but pre-descent refueling becomes less expensive (since the Starship can return to EDL, rather than propulsive LEO), which gives you a lot more wiggle-room on abort contingencies.

It is possible that crew certification for Starship launch and EDL comes early enough that milestone #2 never needs to be dealt with.  I'd be surprised if that were true, but I've been surprised before.

_________________
¹Note that I'm not talking about Mars, not because I don't think it'll happen, but rather because it's easy:  just refuel once in VLEO and you're good to go.
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