4 ms·

Most modern armor seems to aim to disrupt a projectile before it can penetrate. The wikipedia page says this type of armor is in use on the ISS already: "Whip

Most modern armor seems to aim to disrupt a projectile before it can penetrate. The wikipedia page says this type of armor is in use on the ISS already: "Whipple shields consist of a relatively thin outer bumper spaced some distance from the main spacecraft wall. The bumper is not expected to stop the incoming particle or even remove much of its energy, but to break up and disperse it, dividing the original particle energy among many fragments that fan out between bumper and wall. The original particle energy is spread more thinly over a larger wall area, which is more likely to withstand it. A direct analogy is that a lighter bullet resistant vest is needed to stop a load of birdshot than a single rifle bullet with the same total mass and kinetic energy." https://en.wikipedia.org/wiki/Whipple_shield https://en.wikipedia.org/wiki/Whipple_shield Even on Earth, I have the impression that modern armor is a long way from just using thicker steel: https://en.wikipedia.org/wiki/Dynamic_armour https://en.wikipedia.org/wiki/Dynamic_armour https://en.wikipedia.org/wiki/Composite_armour https://en.wikipedia.org/wiki/Composite_armour

jacquesm 5y ago
You can link to wikipedia pages all day long but in reality there just isn't any viable defense against a collision at orbital velocities with anything that weighs more than a couple of grams. Also: whatever armor you want to put on your space ship needs to be launched first and brought up to the same speed as the rest of the vehicle, and this amount of mass will have to be accelerated again every time you want to fix your orbit.
- perl4ever 5y ago
  > anything that weighs more than a couple of grams So where are you reading about the size distribution of the debris?
  - jacquesm 5y ago
    Here https://en.wikipedia.org/wiki/Kosmos_1408 https://en.wikipedia.org/wiki/Kosmos_1408 and here https://www.reuters.com/world/us-military-reports-debris-generating-event-outer-space-2021-11-15/ https://www.reuters.com/world/us-military-reports-debris-gen... A 2.2 ton satellite + whatever the mass of the anti satellite weapon creates a cloud of 1500 trackable fragments, so fragments large enough to be tracked by radar from Earth. See here: https://www.nasa.gov/mission_pages/station/news/orbital_debris.html https://www.nasa.gov/mission_pages/station/news/orbital_debr... "There are approximately 23,000 pieces of debris larger than a softball orbiting the Earth. They travel at speeds up to 17,500 mph, fast enough for a relatively small piece of orbital debris to damage a satellite or a spacecraft. There are half a million pieces of debris the size of a marble or larger (up to 0.4 inches, or 1 centimeter) or larger, and approximately 100 million pieces of debris about .04 inches (or one millimeter) and larger. There is even more smaller micrometer-sized (0.000039 of an inch in diameter) debris. Even tiny paint flecks can damage a spacecraft when traveling at these velocities. A number of space shuttle windows were replaced because of damage caused by material that was analyzed and shown to be paint flecks. In fact, millimeter-sized orbital debris represents the highest mission-ending risk to most robotic spacecraft operating in low Earth orbit." So, that's 2.2 tons, split up into 1500 larger pieces (anywhere from a few cm upwards) which is > 5% of the larger pieces that were already in orbit, and a multitude of smaller objects. Each of these has the capability to damage or destroy other spacecraft in that orbit.

jacquesm 5y ago

You can link to wikipedia pages all day long but in reality there just isn't any viable defense against a collision at orbital velocities with anything that weighs more than a couple of grams. Also: whatever armor you want to put on your space ship needs to be launched first and brought up to the same speed as the rest of the vehicle, and this amount of mass will have to be accelerated again every time you want to fix your orbit.

perl4ever 5y ago
> anything that weighs more than a couple of grams So where are you reading about the size distribution of the debris?
- jacquesm 5y ago
  Here https://en.wikipedia.org/wiki/Kosmos_1408 https://en.wikipedia.org/wiki/Kosmos_1408 and here https://www.reuters.com/world/us-military-reports-debris-generating-event-outer-space-2021-11-15/ https://www.reuters.com/world/us-military-reports-debris-gen... A 2.2 ton satellite + whatever the mass of the anti satellite weapon creates a cloud of 1500 trackable fragments, so fragments large enough to be tracked by radar from Earth. See here: https://www.nasa.gov/mission_pages/station/news/orbital_debris.html https://www.nasa.gov/mission_pages/station/news/orbital_debr... "There are approximately 23,000 pieces of debris larger than a softball orbiting the Earth. They travel at speeds up to 17,500 mph, fast enough for a relatively small piece of orbital debris to damage a satellite or a spacecraft. There are half a million pieces of debris the size of a marble or larger (up to 0.4 inches, or 1 centimeter) or larger, and approximately 100 million pieces of debris about .04 inches (or one millimeter) and larger. There is even more smaller micrometer-sized (0.000039 of an inch in diameter) debris. Even tiny paint flecks can damage a spacecraft when traveling at these velocities. A number of space shuttle windows were replaced because of damage caused by material that was analyzed and shown to be paint flecks. In fact, millimeter-sized orbital debris represents the highest mission-ending risk to most robotic spacecraft operating in low Earth orbit." So, that's 2.2 tons, split up into 1500 larger pieces (anywhere from a few cm upwards) which is > 5% of the larger pieces that were already in orbit, and a multitude of smaller objects. Each of these has the capability to damage or destroy other spacecraft in that orbit.