This is what happens to aluminum when hit by a 1/2 oz (~14g) piece of plastic going 15,000 mph (~24000 km/h) in space

#Hypervelocity

shows the violence a little piece of orbiting space debris can wreak on a spacecraft

#Hypervelocity

That’s the great thing about Kinetic Energy (KE):

KE = ½mv^2

Velocity is *far* more important than mass. Doesn’t matter how light something is...if it’s moving really fast, it can pack a serious punch!

#Hypervelocity

For quick reference:

a high-powered rifle bullet goes about 1500 mph

(wayyy slower than that 15000 mph plastic space debris!)

#Hypervelocity

So how do we protect spacecraft against this orbital shooting range?

Advanced Shields

There are various concepts that have been developed and tested, and now help to protect spacecraft like the @Space_Station

Here are some different types...

#Hypervelocity

This is a “Monolithic Shield”

It’s your brute force approach and does not win any points for ingenuity.

It’s simply a slab of aluminum capable of absorbing the entire force of the impact.

#Hypervelocity

This is a “Whipple Shield”

It’s the first spacecraft shield ever implemented. Introduced by Fred Whipple in the 1940’s, it’s still used today.

It uses a sacrificial bumper -usually aluminum- in front of the spacecraft, allowing it to absorb the initial impact.

#Hypervelocity

This is a “Stuffed Whipple” Shield

It’s a variation of the simple Whipple.

Layers of Nextel and Kevlar are inserted between the bumper and rear wall to shock and pulverize the debris cloud even more

#Hypervelocity

This is a “Multi Shock Shield”

This is a popular design

It staggers layers of Nextel at specified standoff distances. The multiple layers repeatedly shock that debris until the remaining fragments are harmless against the rear wall.

#Hypervelocity

This is a “Honeycomb Panel”

Many spacecraft are designed using Aluminum honeycomb sandwich panel structures (what’s with all the food refs?).

These panels are tested and evaluated for their MMOD shielding capabilities.

MMOD = MicroMeteoroid and Orbital Debris

#Hypervelocity

This is a “Foam Panel”

Metallic foam sandwich panels provide structural support - they’re similar to honeycomb panels, but have improved MMOD shielding capabilities.

Metallic foam panels are being tested and evaluated for future spacecraft designs.

#Hypervelocity

Lastly, this is a “Transhab Shield”

This shield is a prototype developed for a future human-rated mission to Mars, and consists of layers of Mylar, Nextel, Kevlar, & Foam (cored out).

Foam is used because it’s desired that shielding be compressible for launch.

#Hypervelocity

For more information on shield development and hypervelocity impact technologies:

@Astromaterials

https://hvit.jsc.nasa.gov/shield-development/

#Hypervelocity

...and then I found the videos...

#Hypervelocity

This is an impact test for the @Space_Station lab module shielding

Purpose: generate damage representative of potential impacts on the ISS

Video: a ~0.4 inch (10 mm) aluminum sphere “micrometeoroid” impacting an orbital debris shield @ 12300 mph (~19800 km/hr)

#Hypervelocity

For any fans of shooting/marksmanship *and* space sciences, I think I found your perfect job:

High Velocity Impact Testing and Advanced Spacecraft Shielding Materials.

https://hvit.jsc.nasa.gov/hypervelocity-testing/

#Hypervelocity #Engineering