Science News Thread (for articles that don't relate to ongoing discussions)

[JoeSchmuckatelli]

4 minutes ago, AckSed said:

I'll exert the effort

Only wish I could give another up-thumb!

[darthgently]

4 hours ago, AckSed said:

I've already spent two hours on this so I will admit that for airlines, it's weak.

What about replacing much of the aluminum bulkheads and stringers in aircraft?  The skin?  Costs could also come down quite a bit if aircraft and auto manufacturer boom the market scale for it, in the longer run, and scarcity is not a big issue.

I'm also curious about the fatigue curve vs aircraft Al alloys

[DDE]

How do explosives "flow" around obstacles?

I'm specifically wondering what would happen if an ERA brick went off next to a rifle stuck out of a vehicle firing port. Let's omit the fact that ERA-equipped vehicles tens to have the firing ports plated over.

Spoiler

 

[kerbiloid]

It would be something weaker than HEAT coming in.

And even weaker than an uranium arrow.

[darthgently]

4 hours ago, DDE said:

How do explosives "flow" around obstacles?

I'm specifically wondering what would happen if an ERA brick went off next to a rifle stuck out of a vehicle firing port. Let's omit the fact that ERA-equipped vehicles tens to have the firing ports plated over.

  Hide contents

I would guess it would be loosely analogous to cross-section size of ports minus cross-section size of obstruction at port (like piston diameter in hydraulics) and distance (determining amount of force applied)

Edited December 11, 2023 by darthgently

[DDE]

21 minutes ago, kerbiloid said:

It would be something weaker than HEAT coming in.

And even weaker than an uranium arrow.

I'm more interested in whether ERA and firing ports are compatible at all. Omitting exotic variants such as fixed firing port weapons like the M231.

[darthgently]

1 hour ago, DDE said:

I'm more interested in whether ERA and firing ports are compatible at all. Omitting exotic variants such as fixed firing port weapons like the M231.

My understanding is that ERA uses a highly directional shaped charge aimed outward.  The pressure wave to an adjacent port is probably much less than along the main vector

[Codraroll]

2 hours ago, darthgently said:

My understanding is that ERA uses a highly directional shaped charge aimed outward.  The pressure wave to an adjacent port is probably much less than along the main vector

Necessarily, there will also be a pressure wave going back towards the vehicle. Symmetry of forces and all that. I guess it would propagate through the vehicle and give all the rifles in the firing ports a great big smack that might permanently screw up their aim.

It seems that some people were asleep during that part of physics class:

Edited December 11, 2023 by Codraroll

[darthgently]

47 minutes ago, Codraroll said:

Necessarily, there will also be a pressure wave going back towards the vehicle. Symmetry of forces and all that. I guess it would propagate through the vehicle and give all the rifles in the firing ports a great big smack that might permanently screw up their aim.

It seems that some people were asleep during that part of physics class:

Still, I'd rather have windshield stuff coming in at velocity N then an RPG exploding inside the cab with larger pieces at N x 1000 velocity.  But point seriously taken.  None are good options

[kerbiloid]

15 hours ago, DDE said:

I'm more interested in whether ERA and firing ports are compatible at all. Omitting exotic variants such as fixed firing port weapons like the M231.

-1 man vs -7 men

Also, there are non-explosive systems.

12 hours ago, Codraroll said:

It seems that some people were asleep during that part of physics class:

Yes, because they don't know that pressure = force/area, and that the total mass of the carriage is too great for one small charge.

Also, it's anyway hard to take aim from the moving APC, so the accuracy isn't affected too much.

[darthgently]

Shaped charges are highly directional.  One can stand behind a claymore and not get pulverized.  There is a reason it reads "FRONT TOWARD ENEMY" on the dangerous side.  I'm not saying it would be comfortable inside the cabin with gun ports when the armor went off, but much better than not partially redirecting an incoming RPG

[Codraroll]

13 hours ago, kerbiloid said:

Also, there are non-explosive systems.

Aye, plenty of examples there too:

[magnemoe]

On 12/11/2023 at 10:53 AM, DDE said:

How do explosives "flow" around obstacles?

I'm specifically wondering what would happen if an ERA brick went off next to a rifle stuck out of a vehicle firing port. Let's omit the fact that ERA-equipped vehicles tens to have the firing ports plated over.

  Hide contents

 

Think gun ports on APC has fallen out of use quite a bit. They are pretty pointless then driving around as you get bumped around and has very limited visibility. Then stopped the infantry should most time go out and fight as infantry. 
If environment is to dangerous as in lots of shell fire, don't stop. Russia learned they also made the infantry wanting to fight from inside the APC rater than outside. 
Think remote gun stations is an much better idea as they are stabilized and can have good optic. 

And explosive reactive armor is dangerous for the tank and more so for people around it, you accept loosing some systems. (An use for an dual gun tank? Second gun projectile is 10 meter behind and almost hypersonic   )

On 12/11/2023 at 7:13 PM, Codraroll said:

Necessarily, there will also be a pressure wave going back towards the vehicle. Symmetry of forces and all that. I guess it would propagate through the vehicle and give all the rifles in the firing ports a great big smack that might permanently screw up their aim.

It seems that some people were asleep during that part of physics class:

Yes this looks just stupid, use cage armor instead. One idea to protect armored cars is something like external airbag who grabs the RPG, it probably not even detonate like mostly on cage armor and if it does the stand of distance is increased. Yes it would need lots of sensors to activate more so an an rpg is not powered in flight. If you are in an armored car and targeted by an guided anti tank missile, you have very serious problems. 

[Codraroll]

1 hour ago, magnemoe said:

If you are in an armored car and targeted by an guided anti tank missile, you have very serious problems.

Finding oneself in a Scooby Doo van in the middle of hostile RPG territory is the culmination of pretty poor life choices all around. Weighing the poor engine down with explosive blocks that limit the vision of the driver will not be the ticket out of there, to put it like that.

EDIT: Or probably, it will. Just not in the direction of home. Well, not just in the direction of home.

Edited December 12, 2023 by Codraroll

[darthgently]

2 hours ago, magnemoe said:

Think remote gun stations is an much better idea as they are stabilized and can have good optic. 

This is the take home.  With robotic parts and electronic optics off the shelf now definitely the way to go

[kerbiloid]

So, T-55 is the best APC.

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

They should restart its production.

[SunlitZelkova]

17 hours ago, kerbiloid said:

So, T-55 is the best APC.

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

They should restart its production.

https://ru.m.wikipedia.org/wiki/QN-506
 

Type 59 (T-54) chassis, basically BMP Terminator Chinese style.

[AckSed]

Honeybee Robotics developing a solar stick insect mesh network surveillance tower street light ALL of them: https://www.honeybeerobotics.com/news-events/honeybee-robotics-to-develop-lunarsaber-for-darpas-luna-10-program/

[darthgently]

17 minutes ago, AckSed said:

Honeybee Robotics developing a solar stick insect mesh network surveillance tower street light ALL of them: https://www.honeybeerobotics.com/news-events/honeybee-robotics-to-develop-lunarsaber-for-darpas-luna-10-program/

This is a great niche to tackle.  Clever

[kerbiloid]

4 hours ago, AckSed said:

Honeybee Robotics developing a solar stick insect mesh network surveillance tower street light ALL of them: https://www.honeybeerobotics.com/news-events/honeybee-robotics-to-develop-lunarsaber-for-darpas-luna-10-program/

 

Spoiler

A mystically glowing lunar fog under the mast.

Are they aware, that there is no air on the Moon, so the light spot will be almost invisible from distance?

[AckSed]

8 hours ago, kerbiloid said:

A mystically glowing lunar fog under the mast.

Are they aware, that there is no air on the Moon, so the light spot will be almost invisible from distance?

It says to me, "We took the first person we could find in the office with Blender skills and told them to finish this render over the weekend."

The thing that makes me blink a bit is that this is supposed to be 100 metres tall. It can work, especially in Lunar gravity with no air, but if they pack all those collapsible booms, thin-film solar panels, electronics and lights on the top into the base, this is going to have the structural integrity of a crisp packet. It won't need more, but still.

Edited December 15, 2023 by AckSed

[kerbiloid]

They should add a rotating disco ball on top, rotating in the heat flow from surface.

[kerbiloid]

https://blogs.nasa.gov/sunspot/2023/12/12/engineers-working-to-resolve-issue-with-voyager-1-computer/

Voyager starts sending binary data.

Spoiler

 

Then...

Spoiler

 

 

 

[DDE]

TL:DR The Earth was already experiencing volcanic winters (up to -10°C global anomaly) and choking on toxic fumes before the asteroid offed the dinosaurs

Recurring volcanic winters during the latest Cretaceous: Sulfur and fluorine budgets of Deccan Traps lavas

Quote

Two events share the stage as main drivers of the Cretaceous-Paleogene mass extinction-Deccan Traps volcanism, and an asteroid impact recorded by the Chicxulub crater. We contribute to refining knowledge of the volcanic stressor by providing sulfur and fluorine budgets of Deccan lavas from the Western Ghats (India), which straddle the Cretaceous-Paleogene boundary. Volcanic fluorine budgets were variable (400 to 3000 parts per million) and probably sufficient to affect the environment, albeit only regionally. The highest sulfur budgets (up to 1800 parts per million) are recorded in Deccan lavas emplaced just prior (within 0.1 million years) to the extinction interval, whereas later basalts are generally sulfur-poor (up to 750 parts per million). Independent evidence suggests the Deccan flood basalts erupted in high-flux pulses. Our data suggest that volcanic sulfur degassing from such activity could have caused repeated short-lived global drops in temperature, stressing the ecosystems long before the bolide impact delivered its final blow at the end of the Cretaceous.

https://pubmed.ncbi.nlm.nih.gov/37792933/

[AckSed]

NASA gifts a Phase 1 grant to a new way of cooling I haven't ever considered - bling!

https://www.nasa.gov/general/electro-luminescently-cooled-zero-boil-off-propellant-depots/

By using all the normal approaches (vacuum insulation, thermal shields), and then plating the non-sunward side of a fuel depot in LEDs, you just might be able to achieve zero boil-off storage of H2, thanks to a little quirk of physics.