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Super Heavy has splashed down in The Gulf of Mexico

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Re: Super Heavy has splashed down in The Gulf of Mexico

#831

Post by MeImCounting »

somenameforme wrote: post #672
MeImCounting wrote: post #529

Earlier quoted context omitted.

The problem is that paradoxically, thicker shields can cause higher doses of radiation due to secondary radiation production. Theres a balance there to minimizing primary and secondary dosage but you cant really get it below a certain threshold without some form of active shielding. Theres a lot of promising ideas for active shielding but they all require alot of power. All this to say that someone on a trip to mars…

The secondary radiation you're talking about is called bremsstrahlung (braking) radiation [1]. This is precisely why water is, to my knowledge, the current leading idea. It works not only as an excellent primary shield but also helps to minimize secondary radiation, and you also naturally have literally tons of it. As an aside, this is why the original Moon missions used simple aluminum. One of the typical angles peo…

Polyethylene is similarly a good shield because its got high hydrogen content so is pretty good at moderating neutrons. I image a polyethylene structure containing a layer of water is probably something like what we'll end up settling on. Its also quite strong and would make decent structural components.

Re: Super Heavy has splashed down in The Gulf of Mexico

#832

Post by sc0ttyd »

adolph wrote: post #616
pixl97 wrote: post #417

Earlier quoted context omitted.

I mean the old rocket landings threw away 90%+ of the rocket first. Minus the hot staging ring and some molten metal almost all of this rocket was present at both its landings.

The flying bedstead of 1964 was a reusable rocket that propulsively la ded and was reused. It didn’t go very high tho. . . https://www.nasa.gov/image-article/flying-bedstead/

No it wasn't. It was powered by a jet engine. Specifically, a GE CF700.

https://en.wikipedia.org/wiki/Lunar_Landing_Research_Vehicle

Re: Super Heavy has splashed down in The Gulf of Mexico

#833

Post by philwelch »

me_me_me wrote: post #766
philwelch wrote: post #658

Earlier quoted context omitted.

No, that’s when WW2 became a pan-European war. It became a world war when Japan attacked the British and Americans, thus combining the Anglo-German and Sino-Japanese wars into a single conflict.

Calling it a single conflict is bit of hair splitting, japan had almost nothing to do with germany, especially after war started. Those were 2 separate conflicts happening at the same time.

Part of what combined the two conflicts, aside from Allied questions about resource allocations and priorities, was the supply lines of the British Empire. There was a continuous series of supply lines running all the way from England to Burma, through the Mediterranean and Suez Canal and down through South Asia. The Suez Canal (under threat from the Italians and Germans) was part of the exact same supply line as the Burma Road (under threat from the Japanese).

Re: Super Heavy has splashed down in The Gulf of Mexico

#834

Post by echoangle »

erkt wrote: post #783
echoangle wrote: post #503

Earlier quoted context omitted.

I would compare it to Airplanes, and there are not a lot of rust-bucket airplanes, because just like in space, failures can lead to unavoidable death very quickly. That’s not comparable to a reliable pickup

Lots of private planes from the 70’s still being flown, there’s a little cosmetic rust..

Those are getting overhauls in regular intervals though, it’s more like theseus airplane. Except for the structure itself, there is a lot of repair and replacement happening. And they also have a less-than-great safety record (although that is also pilot related).

Re: Super Heavy has splashed down in The Gulf of Mexico

#835

Post by philwelch »

czl wrote: post #684
philwelch wrote: post #656

Earlier quoted context omitted.

There’s a much simpler theory of the war, which is that it was Germany that was worried about a foreign rival catching up to them—Russia—which is why Germany pushed for the war to start. It’s interesting to see this theory projected onto the British, but there’s a fatal flaw with this projection. The first declaration of war was by Austria-Hungary against Serbia. Britain was not in a position to manipulate the situat…

> The 99 years between the Napoleonic and First World Wars were the most peaceful 99 years of European history since at least the Roman Empire; You make a good point about the "Long Peace" between the Napoleonic Wars and World War I. While there were indeed several conflicts during this period, they were generally shorter and more localized. The Revolutions of 1848, which affected many European countries. The Russo-T…

> And there are others that I missed

For instance, the Franco-Prussian war of 1870, where the German Empire you seem to idolize was effectively born. Also the same war that gave the German Empire a degree of overconfidence about their chances against France.

> however had Britain remained neutral and not created alliances that it knew would put it in conflict with Germany is it possible that the Germany vs. Russia conflict might have remained a regional war (like others I mentioned above)

Did Britain create the alliance between France and Russia? They certainly weren't a party to it, because that wasn't their casus belli for entering the war. Their casus belli was the German invasion of Belgium. My contention is that if Britain was less neutral and more proactive about creating alliances that could put it in conflict with Germany, they could have successfully deterred the First World War.

Re: Super Heavy has splashed down in The Gulf of Mexico

#836

Post by Aeolun »

pie420 wrote: post #797
Aeolun wrote: post #735

Earlier quoted context omitted.

> This option turns out to have had the lowest bodycount in the end Given that you don’t know the body count of the other options, given they didn’t happen, that’s a bold statement to make.

The firebombing of tokyo killed 200K people, more than both nukes. the firebombing was an attempt to end the war via conventional means and it did nothing to weaken japanese resolve. The reason hiroshima and nagasaki (small cities) were chosen as nuke targets was because every other bigger city was already mostly destroyed due to firebombing campaigns.

I am not sure how this is relevant to the point I made. Lots of people died. You still don’t know (and never will) how much would have died due to the other options. It’s speculation at best.

Re: Super Heavy has splashed down in The Gulf of Mexico

#837

Post by FredPret »

pdonis wrote: post #824
FredPret wrote: post #631

Earlier quoted context omitted.

My original and subsequent posts were that the nuke made the world safer. Post-1945 battle deaths dropped to near-zero by comparison to pre-1945. Even one battle death is too many but having them go down overall is very good.

> My original and subsequent posts were that the nuke made the world safer. Post-1945 battle deaths dropped to near-zero by comparison to pre-1945. Post hoc ergo propter hoc is a well known logical fallacy. That is what you are doing here. Also, the relevant comparison, as I said before, is not post-1945 vs. pre-1945. It is something like post-1945 vs. pre-1914, so that the comparison involves peacetime conditions on…

I’m claiming a direct causality between how terrible the nukes were and how peaceful the subsequent decades have been.

The cold war was cold because of M.A.D.

And I will compare any periods I want. The nukes fell in 1945, so I compare all of human history before that and after that. There’s a clear and massive decline even if you only look at pre-1914 rates.

Re: Super Heavy has splashed down in The Gulf of Mexico

#838

Post by FredPret »

Aeolun wrote: post #738
FredPret wrote: post #608

Earlier quoted context omitted.

Point me to the rapes of Nanking the allies did. Or maybe just stop spreading Soviet propaganda.

Uh, 2000 years of European history not enough? Just because it happened a few hundred years earlier doesn’t make it better.

Yes it does. Moral progress is a real thing. Standards rise over time. Alexander the Great would be a war criminal today, and yet he was considered a relatively easygoing ruler at the time.

Re: Super Heavy has splashed down in The Gulf of Mexico

#839

Post by cryptonector »

cubefox wrote: post #815
skissane wrote: post #646

Earlier quoted context omitted.

> Getting it human rated for landing on Earth seems infeasible. Why? For NASA, human-rating - for either Earth launch or Earth re-entry - requires a very detailed engineering analysis of probability of loss-of-crew (LOC), and then NASA has some maximum LOC probability they allow (for NASA Commercial Crew, both launch and landing it is 1-in-500, which is 0.2%-for whole of mission it is 1-in-270). That analysis is base…

> However, they don’t actually have to land it 500 times - all they need is an engineering analysis That very analysis will include the fact that they have no launch abort system like normal capsule based systems and that the belly flop landing is much more dangerous than landing a capsule. Space Shuttle memories may come to mind. So the only realistic way to get the 1 in 500 confidence would probably be to really la…

Starship separation from booster could be the launch abort system. There is no landing abort system.

My concern is that the flip maneuver is just too risky for landing with people on board even if Starship manages to do 200 perfect landings in a row (that would be a better record than the Shuttle).

Re: Super Heavy has splashed down in The Gulf of Mexico

#840

Post by cryptonector »

was_a_dev wrote: post #688
cryptonector wrote: post #636

Earlier quoted context omitted.

Getting human rated for launching seems feasible. Getting it human rated for landing on Earth seems infeasible.

Absolute worst case, Starship delivers a couple of Dragon capsules to LEO for crew transfer and return

This is my expectation.
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