For Questions That Don't Merit Their Own Thread

[kerbiloid]

Give the grey google to the grey goo.

Quote

Machines making machines. How perverse

That was the purpose of the monkey upgrade 2Mya.

So, there is nothing more natural.

[DDE]

3 hours ago, ARS said:

In space, if you use an extremely powerful directional microwave emitter (more than what spacecraft hazard protection designed for), could you actually blow up incoming target (fighters, missiles, ships, etc.) by cooking up their warhead/ ammunition? Or for the short version, could you cause ammo cook-off by using directional microwave? (which in turn, caused magazine detonation)

Modern explosives are really, really heat-insensitive, precisely because nobody wants fires to turn into explosions.

That said, I recall a US DoD or DoD-adjacent graphic listing microwaves as a space-to-space weapon, probably not targeting explosives though.

[adsii1970]

7 minutes ago, DDE said:

Modern explosives are really, really heat-insensitive, precisely because nobody wants fires to turn into explosions.

That said, I recall a US DoD or DoD-adjacent graphic listing microwaves as a space-to-space weapon, probably not targeting explosives though.

During World War II, there was considerable research done by both the United States, Germany, and Japan to use microwave-based weaponry in combat in the later years (1944-45) of the war. Because of wanting to keep the forum at a PG-13 rating, I will not go into any more details than that. 

[kerbiloid]

23 minutes ago, adsii1970 said:

During World War II, there was considerable research done by both the United States, Germany, and Japan to use microwave-based weaponry in combat in the later years (1944-45) of the war. Because of wanting to keep the forum at a PG-13 rating, I will not go into any more details than that. 

They have seen a teleport failure in StarTrek.

[magnemoe]

4 hours ago, kerbiloid said:

Possible, but makes not much sense due to the long wave length.

The beam divergence angle (rad) is ~ 1.22 * wavelength / optics_aperture (the mirror diameter or so)

So, the softer is the radiation, the wider is the beam, and you need as short wavelength as possible (preferrably, Xray or gamma). 
The IR emitter is used just due to the technical possibility, not because its long waves are in any sense good.

Also, a microwave advantage can be that the mist and clouds are transparent for it, but also only for short ranges.

An more likely effect is that the microwaves will induce charge in wires, this can jam internal systems like control wires to the fins on an missile. Now you can shield against this for internal systems. You can not shield antennas. Also shielding stuff like solar panels will be hard but here its hard to do damage unless you burn out the electronic who will be very hard, easier to burn out control systems. 

As I understand some planes like F-22 can use their radar for this. One benefit is that this is an pretty none lethal air to air weapon if used carefully.  Jamming the fly by wire system is not exactly non lethal  

[kerbiloid]

5 minutes ago, magnemoe said:

An more likely effect is that the microwaves will induce charge in wires, this can jam internal systems like control wires to the fins on an missile.

The missile is designed to withstand EMI of a close nuke, while the MW emission would spread in a cone.
So, the killing range would be not so wide.

6 minutes ago, magnemoe said:

Now you can shield against this for internal systems. You can not shield antennas.

1. You can keep them disabled until they get required.
2. If an unusual radiosignal gets in, the missile would screw the antennas at all and perform a direct hit.

8 minutes ago, magnemoe said:

Also shielding stuff like solar panels

On a missile?

8 minutes ago, magnemoe said:

As I understand some planes like F-22 can use their radar for this.

If they get close to. But if a nuke has already gotten so close, it's late to fry it, it will just either hit directly or explode immediately.

[magnemoe]

1 hour ago, adsii1970 said:

During World War II, there was considerable research done by both the United States, Germany, and Japan to use microwave-based weaponry in combat in the later years (1944-45) of the war. Because of wanting to keep the forum at a PG-13 rating, I will not go into any more details than that. 

The US has an microwave area denial microwave pain weapon, probably safer than an shield wall and batons. And intended to be used against violent mobs with dangerous weapons. Rescuing besieged military police with gunships causes more causalities. 

[magnemoe]

5 minutes ago, kerbiloid said:

The missile is designed to withstand EMI of a close nuke, while the MW emission would spread in a cone.
So, the killing range would be not so wide.

1. You can keep them disabled until they get required.
2. If an unusual radiosignal gets in, the missile would screw the antennas at all and perform a direct hit.

On a missile?

If they get close to. But if a nuke has already gotten so close, it's late to fry it, it will just either hit directly or explode immediately.

Yes most advanced weapons are well shielded. This would probably burn out an civilian drone pretty easy.  Guess lots of the cheaper war on terror stuff would also be vulnerable. 
1 agree. 
2 if you jam the control surfaces on an missile or white out its radar it will miss you unless you also disrupt the IR sensors if it has it  

Satellite, and other systems is easier to jam here and damaging something is an attack. 

Nuclear war is for ballistic missile carrying submarines not fighter jets. 
I assume the F-22 system is kind of close in self defense against incommoding missiles, like tanks has an heavy machine gun for AA  
Now it could be useful in some cases and the non lethal harassment  is often important in soft gunboat diplomacy. 
 

[DDE]

3 minutes ago, magnemoe said:

it will miss you unless you also disrupt the IR sensors if it has it  

Importantly, infrared seems more popular in anti-space weapons. And those DIRCM crystal balls seem pretty compact, to boot.

 

[kerbiloid]

19 minutes ago, magnemoe said:

2 if you jam the control surfaces on an missile or white out its radar it will miss you unless you also disrupt the IR sensors if it has it

If it's nuke and enough close to enable the antennas and to  jam them with MW, it's probably already looking in the target direction, so the inertial guiding will stick it into ground enough close to nuke it.

Bombs and reentry vehicles definitely so.

[JoeSchmuckatelli]

2 hours ago, magnemoe said:

like tanks has an heavy machine gun for AA

(as a former tanker) 

 

[SOXBLOX]

2 hours ago, magnemoe said:

I assume the F-22 system is kind of close in self defense against incommoding missiles

IDK about the F-22, but the F-35 has a similar radar, and they can use it for electronic attack on enemy radars. Not sure if that means high-power jamming or actually cooking the electronics. I do know that there are a number of programs underway (one from Raytheon and one specific to the Army) that will use microwave emitters for frying circuitry. It's mainly an anti-drone/C-RAM system, though.

[DDE]

49 minutes ago, JoeSchmuckatelli said:

(as a former tanker) 

 

It's all relative.

Spoiler

 

[JoeSchmuckatelli]

Observatories complain that SX's constellations of satellites interfere with their long exposure observations.

When I see satellites, they're always visible just shortly after sunset.  Obviously I am using only the Mark 1 Eyeball, and during this post-sunset to EENT period I can imagine that high tech equipment might get satellites running across their imagers.

But.

Do observatories have problems with satellites interfering with observations after EENT?

 

[kerbiloid]

The astronomers are too pampered.

It's just 1 800 on LEO of 12 000 (plus OneWeb, plus others), and they already started whining.

What are they going to start when there will be thirty times more sats in the sky?

 

The solution is simple.

Spoiler

 

Put this on a telescope, to see the stars you need,

[Gargamel]

Serious question I’m asking for a friend.... no really.     
 

If one wished to ship / have delivered lobster to an individual in Thailand, what would be the best option?   

[FleshJeb]

9 minutes ago, Gargamel said:

Serious question I’m asking for a friend.... no really.     
 

If one wished to ship / have delivered lobster to an individual in Thailand, what would be the best option?   

Put a leash on it and bring it on the plane as an Emotional Support Lobster.

Or: https://www.cagettebkk.com/product/lobster-maine-750g/

(I just googled “deliver lobster to Thailand”)

[Gargamel]

2 hours ago, FleshJeb said:

(I just googled “deliver lobster to Thailand”)

His Google fu isn’t nearly as good.   He’s been trying to figure out a way to ship a live lobster from the US.    Thanks.   This will work nicely.  

[SunlitZelkova]

5 hours ago, JoeSchmuckatelli said:

Observatories complain that SX's constellations of satellites interfere with their long exposure observations.

When I see satellites, they're always visible just shortly after sunset.  Obviously I am using only the Mark 1 Eyeball, and during this post-sunset to EENT period I can imagine that high tech equipment might get satellites running across their imagers.

But.

Do observatories have problems with satellites interfering with observations after EENT?

 

I can't answer exactly (quick internet search did not reveal when EENT is), but here are some personal experiences that may help in answering it.

Between 12:15 AM and 1:30 AM PST is often when I would use my telescope during the most recent summer. I often take breaks, and during this time I can still see satellites/space objects regularly, both high and low inclination. And then on other days I would just go out for a short while to see the stars, at between 3:00 AM and 4:15 AM PST, and satellites would still be very clearly visible.

This is while living reasonably close to a large city with the associated light pollution, while gazing at the stars only a dozen meters away from an LED street lamp (albeit facing away from it)!

[DDE]

I don't think this has a thread.

 

[JoeSchmuckatelli]

@DDEWhat was it pooping out the back before the chute deployment? 

Was it trying to light an engine that failed? 

3 hours ago, SunlitZelkova said:

satellites would still be very clearly visible

That's interesting.  I've only seen them before / after sunrise & sunset - and thus presumed that's the only time they are visible. 

Wasn't until I read articles about observatories complaints that I thought about it again... 

So - I guess it's safe to presume that unless the satellite is in the Earth's umbra, it's illuminated.  That's a whole lot of sky. 

Makes Webb that much more important! 

Edited December 2, 2021 by JoeSchmuckatelli

[JoeSchmuckatelli]

This quote from Tim Dodd has me wondering something:

Quote

This is him admiring Rocket Lab’s Electron rocket, which is largely made from carbon fiber. As he points out, carbon fiber at this scale costs about $180 per kilogram, while most steels are less than $10.

The 'carbon fiber (Rocketlab) vs stainless steel (SX)' debate is not only about materials & performance in all the things a reusable rocket has to do... its also about cost.

So - what's the 'coverage weight' difference between the two?  If steel is heavier than carbon fiber for a given area covered (at the required thickness), how close would the actual completed rockets be in price to manufacture?  (Steel weighs more than CF, thus for the same weight you get a bunch more coverage with CF... )

.

..

.

 

(I've tried googling to figure out how much SS weighs per square foot at 4mm... but my fu is not good today... and I have no idea how thick the CF would be for Rocket Lab per square foot to then try to guess 'skin' costs.

Anyone already done the heavy lifting on this?

 

[K^2]

7 hours ago, JoeSchmuckatelli said:

What was it pooping out the back before the chute deployment? 

It might be actually be ice. Or some chute packing materials, maybe? I don't think this is indicative of any problem.

2 hours ago, JoeSchmuckatelli said:

So - what's the 'coverage weight' difference between the two?

Ultimate strength of steel can be about 50% higher than that of carbon fiber composite. This is approximate, because "steel" varies a lot, and so does carbon fiber. In contrast, density of steel is 4-5 times higher. So by weight, you need about a third of carbon fiber that you do steel. Again, roughly, depending on the exact materials you use and properties you're looking for. But it's very clear that while it helps close the price gap a little bit, it's still many times more expensive to build out of carbon fiber than steel.

[SOXBLOX]

20 hours ago, FleshJeb said:

Put a leash on it and bring it on the plane as an Emotional Support Lobster.

You jest, but it would almost work...

[kerbiloid]

16 hours ago, JoeSchmuckatelli said:

What was it pooping out the back before the chute deployment? 

It was scared by big dark angry bird from whose talons it just escaped, so was pooping with decoys.

P.S.
Btw isn't it a kind of smoke rockets during the nuke tests (to visually mark the moments when the shockwave had passed the corresponding distance)?
 

Spoiler

 

To visually trace the X-38 volumetric path after the decoupling.

00:55, 01:02, 01:06
01:10 + cap jettisonned
five or six in 01:11 .. 01:12 during the chute release
01:18 + chute risers rearranged
01:19

So, you have a set of dots on a 30 s long photo.

Edited December 3, 2021 by kerbiloid