For Questions That Don't Merit Their Own Thread

[Spacescifi]

 

So in spite of the silliness of this subject, I want to know if there would be anything that changed if I snapped my fingers and made the entire moon be composed of BBQ pork spare ribs for the next 4 years. After 4 years I snap and our original moon is back.

Ensuing results I can think of:

 

1. The moon no longer shines as much as it once did. Initially it will look brown, but over time will get darker like mud, and may eventually turn blacl due to the sun charring the surface. Say goodbye bright moon, ony the stars shine for us now.

2. We go back to the moon. And we eat some of it. Why do I say this? According to space.com humans have tasted moon dust out of curiousity and said it tasted like gunpowder. So if we have done that....

3. I don't know how safe eating the surface meat would be, likely would be carcinogenic from being black charred. But mining below tge surface may yield some nutrious tasty results... or not. You can confirm this or guess cause I realky don't know. That's why I asking you. What is the shelf life of BBQ pork spare ribs in vacuum? I know oxidation is less of an issue... or is it? Since all those ribs on top of each other.... I dunno.

Last question: Would you eat it? I would if within the first week and from the ribs a few meters below the surface. What about you?

 

Edited March 8, 2020 by Spacescifi

[kerbiloid]

The pressure will liqufy underlying layers and make the upper layers sink. You'll get a ball of dirty ice.

[Nightside]

7 hours ago, kerbiloid said:

The pressure will liqufy underlying layers and make the upper layers sink. You'll get a ball of dirty ice.

Gravy volcanos 

[ARS]

Could we launch a payload to orbit using V2 rockets arranged in ELV stack? Imagine a V2 rocket, now strap several of them for the 1st stage, then make smaller 2nd stage from the same rocket, then the smaller 3rd stage, and so on... Assuming the payload's mass is around current-day range of space payload, is this possible?

[Nightside]

21 minutes ago, ARS said:

Could we launch a payload to orbit using V2 rockets arranged in ELV stack? Imagine a V2 rocket, now strap several of them for the 1st stage, then make smaller 2nd stage from the same rocket, then the smaller 3rd stage, and so on... Assuming the payload's mass is around current-day range of space payload, is this possible?

Can upper stages be ignited after liftoff of does everything have to be lit on the ground?

[ARS]

Just now, Nightside said:

Can upper stages be ignited after liftoff of does everything have to be lit on the ground?

You can ignite the upper stage after liftoff. The idea of ELV is staging anyway

[DDE]

31 minutes ago, ARS said:

Could we launch a payload to orbit using V2 rockets arranged in ELV stack? Imagine a V2 rocket, now strap several of them for the 1st stage, then make smaller 2nd stage from the same rocket, then the smaller 3rd stage, and so on... Assuming the payload's mass is around current-day range of space payload, is this possible?

The R-7 seems to be actually derived from the literal solution of bolting five A-4s together, so...

[wumpus]

11 hours ago, DDE said:

The R-7 seems to be actually derived from the literal solution of bolting five A-4s together, so...

This surprised me, as the R-7 uses kerosene and LOX not vodka and LOX.  But those engines otherwise look suspiciously like A-4 engines, including turbopumps driven by hydrogen peroxide.  And as far as I can tell, doesn't have an additional stage, although the Vostok appears to have yet another A-4 on top of the previous 5 A-4s.

[kerbiloid]

15 hours ago, ARS said:

Could we launch a payload to orbit using V2 rockets arranged in ELV stack?

The four-stage A9/A10/A11/A12 rocket from the Aggregat rocket family was to deliver 10 t into LEO. Launch mass ~4500 t.

It was using a larger engine than the A9's one (fifty of them in the first stage).

So, probably Von Braun considered the original one insufficient.

And yes, it was to be using Schnapps, though they planned to replace it with kerosene. (And Groettrup later did it in his V2-derived projects).

14 hours ago, DDE said:

The R-7 seems to be actually derived from the literal solution of bolting five A-4s together, so...

Compare it and N-1 not to V2 but to the Groettrup's G-series, derived from V2, designed after WWII, in the USSR, before his repatriation to Germany.

https://www.google.com/search?q=groettrup+rocket&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjV_I6rjY_oAhWuw6YKHcjRArAQ_AUoAXoECAwQAw&biw=2133&bih=1087

(The history of his arrival to the USSR and his wife are great themselves, see the ru wiki.)

Edited March 10, 2020 by kerbiloid

[DDE]

10 hours ago, wumpus said:

But those engines otherwise look suspiciously like A-4 engines, including turbopumps driven by hydrogen peroxide. 

Glushko basically killed the Soviet gas generator school for a decade by using the host aircraft's piston engines on his RATOs.

[DDE]

Can a vibranium shield stop an antiship missile?

More importantly, can you use it skip (infinitely) in the direction of the shore?

So many questions for USS America here...

[DDE]

Can we just have a physics law which states, plainly, that everything has a price?

 

[kerbiloid]

21 hours ago, DDE said:

Can a vibranium shield stop an antiship missile?

More importantly, can you use it skip (infinitely) in the direction of the shore?

It works, but you should swim float go by traverses to use as many vibranium shields as you can.

Spoiler

 

[ARS]

Could nuclear explosion irradiate the ever-changing snowfield? For example, if we drop a nuclear bomb (several if need be) into a snowfield with a constant blizzard, after the resulting explosions, does the ground zero is still irradiated and dangerous after several years, even after the blizzard has buried the irradiated ice layer deep beneath several meters of ice? (Ignoring the radiation that's spread by blizzard)

[kerbiloid]

1. Depends on the blast type (mid-air or on-ground), the soil composition (different elements give different isotopes), and charge construction (fussion:fission ratio, uranium vs plutonium).

2. The ground gets radioactive mostly due to the highly radioactive remains of the charge spread around rather than due to irradiation.

So, a mid-air explosion gives by 1-2 orders of magnitude less radioactivity than an on-ground one.
It mostly irradiates rather than pollutes, so its gz gets almost safe in several days.

The most polluting are in-ground but not totally underground ones, when you blast a charge in a short well.
Say, like the explosion which created the lake of Chagan.

You can take Chagan as a reference point.
https://translate.google.com/translate?hl=ru&sl=ru&tl=en&u=https://ru.wikipedia.org/wiki/Чаган_(озеро)#cite_note-2

https://translate.google.com/translate?hl=ru&sl=ru&tl=en&u=https://ru.wikipedia.org/wiki/Проект_«Чаган»

https://translate.google.com/translate?hl=ru&sl=ru&tl=en&u=https://hi-news.ru/eto-interesno/atomnoe-ozero-chagan-nesbyvshayasya-mechta-sssr.html

1964, 140 kt, in-ground, 94% fusion.
Currently it has 2..8 mrad/hr (normally 0.010..0.020 mrad/h, i.e. ~200 times less).
Some water fauna was released there just4lulz for scientific reasons. Mostly died, but at the same time was not endemic, so would die anyway.
Fearless locals have the cattle drinking from there, but officially it's not considered safe, and it's a bad idea to use that water for food as it contains Co, Cs, and Eu.

2..8 mrad/h * 24 * 365 ~= 20..80 rad/year.
Co and Cs emit mostly gamma, so the coefficient of biological efficiency = 1, and 20..80 rad/y = 20..80 rem/y

Limit for civilians = 0.5 rem/year, for nuclear personnel = 5 rem/year, "considered safe" for a single event = 25 rem.
So, if you are a civilian, you need to weaken the radiation 20..80 / 0.5 ~= 40..160 times to live there.

40..160 = 2⁶..2⁷.
So, you need at least 6..7 "half-dose" layers.

A half-dose for the fallout gamma ~13 cm / density,g/cm³. So for the snow~15 cm.
6..7 * 15 ~= 100 cm.

So, you need a meter thick snow layer to decrease the radiation down to safe values.

If you use several nukes, you need to mulltiply the year dose.
But say 100 nukes * 40..160 = 4000..16000 = 12..14 "half-dose" layers, so just twice thicker, 2 meters of snow.

So, a 2+ m thick layer of frozen water (above the last blast fallout) makes the place relatively safe for living.

Obviously, another charge gives different numbers, this is a reference point.

[DDE]

So, let's take this Italian specops submarine concept.

Its entire hull is a series of toroidal oxygen tanks at 350 atm, used to run the diesels underwater in an early and crude version of Air-Independent Power - practical AIP installations use a Stirling engine instead, but. in a similar manner, requiring an oxidizer tank. This construction method was also claimed to be 5 times stronger than a simple single hull.

Can it do ISRU? Specifically, can the oxygen from the electrolysis be used to replenish the tanks under field conditions, and can all of this be powered by the diesel-generator(s) of a small submarine?

[magnemoe]

2 hours ago, DDE said:

So, let's take this Italian specops submarine concept.

Its entire hull is a series of toroidal oxygen tanks at 350 atm, used to run the diesels underwater in an early and crude version of Air-Independent Power - practical AIP installations use a Stirling engine instead, but. in a similar manner, requiring an oxidizer tank. This construction method was also claimed to be 5 times stronger than a simple single hull.

Can it do ISRU? Specifically, can the oxygen from the electrolysis be used to replenish the tanks under field conditions, and can all of this be powered by the diesel-generator(s) of a small submarine?

Creating oxygen will cost more fuel than you gain oxygen, add that you need to pressurize the oxygen using more fuel. I would rater just compress some air for an burst 
This looks like an nice special operation sub, it has an airlock for an diver probably to cut torpedo nets, much larger than the UK mini subs but also much more capable, don't see an snorkel who looks like its only weakness. 

[DDE]

13 hours ago, magnemoe said:

This looks like an nice special operation sub, it has an airlock for an diver probably to cut torpedo nets, much larger than the UK mini subs but also much more capable, don't see an snorkel who looks like its only weakness. 

Yeah, I suppose they were a bit overconfident in their AIP.

The problem with those capabilities is that they've driven size up quite a bit - close to where the divers may want smaller craft in order to get inside enemy harbour. The French understood this, so their proposal, at only twice the displacement, sacrificed armament for two two-seat 'wet' SDVs.

Spoiler

Ditto the actually built Soviet subs (the Sirena SDV, while deliberately torpedo-sized and torpedo-shaped, does not have a warhead):

Spoiler

It's for this reason one is far more likely to see standard subs outfitted with a lock-out chamber and some sort of a 'wet' (unpressurized) propulsion vehicle like the SEAL SDV, or smaller.

Except, plot twist, the SEALs have spent the last decade trying to get a 'dry' design to ride to the target in (relative) comfort:

http://www.hisutton.com/Dry_Combat_Submersible.html
http://www.hisutton.com/SEALs + USSOCOM next generation sub UOES3.html

[kerbiloid]

A tested specops sub powered by ethanol.

Spoiler

well, mostly. Some food is appreciated, too.

 

 

[DDE]

36 minutes ago, kerbiloid said:

A tested specops sub powered by ethanol.

Oh, you jest, but

Quote

The French MESMA (Module d'Energie Sous-Marine Autonome) system is offered by French shipyard DCNS. MESMA is available for the Agosta 90B and Scorpène-class submarines. It is essentially a modified version of their nuclear propulsion system with heat generated by ethanol and oxygen.

 

[DDE]

6 hours ago, kerbiloid said:

Some food is appreciated, too.

Speaking of that... which of these two is the better troop transport method?

[Dirkidirk]

11 minutes ago, DDE said:

Speaking of that... which of these two is the better troop transport method?

The bike makes you stronger, and thus more fiT fOR FiGting!

[kerbiloid]

5 hours ago, DDE said:

Speaking of that... which of these two is the better troop transport method?

This one.

Spoiler

 

[DDE]

36 minutes ago, kerbiloid said:

This one.

  Hide contents

 

Now, now, some people might need more clues.

[kerbiloid]

Yes, both Genghis Khan and my grandfather used the Mongolian horses in war and approved.

(The difference is: my grandfather's horses were imported, but on the other hand Genghis Khan didn't have an anti-tank gun.)

Edited March 16, 2020 by kerbiloid