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The article doesn't make any mention of stealth. I think stealth would be a key factor in any serious future space war. On general physics principles, it's not

The article doesn't make any mention of stealth. I think stealth would be a key factor in any serious future space war. On general physics principles, it's not difficult to make a space object with close to zero emissions in a specified direction. The inverse-square law is a helpful ally. Active (i.e. radar or lidar) have rapidly diminishing returns: their signal powers scale as distance^{-4}—doubly inverse-square. I'm not sure what response can be invented against a dark space object that shoots dark stealth warheads that detonate in the upper atmosphere.

datadrivenangel 2y ago
A dark space object can be seen when it passes between the observer and stars or other objects, so you need to match the spectrum behind you, which makes it a much harder problem! Being very cold is good for long range stealth, but in low orbit the speeds are high enough that it doesn't help against a savvy adversary.
- perihelions 2y ago
  - "A dark space object can be seen when it passes between the observer and stars or other objects," Those are called transits. They're extraordinarily rare for any single given object. Moreover, there are quadrillions of natural objects transiting stars as a baseline noise rate, which you'd be hard-pressed to distinguish a spacecraft from. One hiding among quadrillions. Even if you were very lucky and both observed, and identified, a spacecraft transiting a star, you've instantly lost it. You would need multiple transits in close succession to recover an orbit (and predict its future positions), something which will statistically never happen.
  - datadrivenangel 2y ago
    If you have a number of anti-orbit laser submarines, I suspect a global network of observer stations that are passively looking for transits that don't have a known source is within your budget
    - perihelions 2y ago
      That doesn't help, since multiple transits are a statistical impossibility no matter how many observers you have. - "for transits that don't have a known source" That's statistically about 100% of them: small, remote asteroids or interstellar objects that have never been catalogued, and are undetectable except via transits.
nradov 2y ago
There is no stealth in space. https://www.projectrho.com/public_html/rocket/spacewardetect.php#nostealth https://www.projectrho.com/public_html/rocket/spacewardetect...
- perihelions 2y ago
  That page isn't really responsive to my comment. I'm not sure what point you're trying to make! Of course if you point a directional radio transmitter at an observer, you are not being stealthy, to that observer. Of course if you power up a 100 gigawatt incandescent rocket motor, you're loudly advertising your presence. (No different than a stealth aircraft using afterburners—they don't). Stealth spacecraft would necessarily avoid doing that. Stealth spacecraft could, to highlight one option from a large decision space, consider cryogenic, cold-gas thrusters with invisible output plumes and zero infrared emissions.
  - nradov 2y ago
    Did you even read the whole page? Using cold gas thrusters doesn't solve anything, especially not if you have a crew on board.
ashoeafoot 2y ago
The goal of actual spacewar is to make a auto railgun bullet hell with near c pellets from outside the system, then move in with railgun drones to lure your opponent into the rain or redirect the rain were the opponent will be forced to go. not to dissimilar to 3d flak.

datadrivenangel 2y ago

A dark space object can be seen when it passes between the observer and stars or other objects, so you need to match the spectrum behind you, which makes it a much harder problem! Being very cold is good for long range stealth, but in low orbit the speeds are high enough that it doesn't help against a savvy adversary.

perihelions 2y ago
- "A dark space object can be seen when it passes between the observer and stars or other objects," Those are called transits. They're extraordinarily rare for any single given object. Moreover, there are quadrillions of natural objects transiting stars as a baseline noise rate, which you'd be hard-pressed to distinguish a spacecraft from. One hiding among quadrillions. Even if you were very lucky and both observed, and identified, a spacecraft transiting a star, you've instantly lost it. You would need multiple transits in close succession to recover an orbit (and predict its future positions), something which will statistically never happen.
- datadrivenangel 2y ago
  If you have a number of anti-orbit laser submarines, I suspect a global network of observer stations that are passively looking for transits that don't have a known source is within your budget
  - perihelions 2y ago
    That doesn't help, since multiple transits are a statistical impossibility no matter how many observers you have. - "for transits that don't have a known source" That's statistically about 100% of them: small, remote asteroids or interstellar objects that have never been catalogued, and are undetectable except via transits.

nradov 2y ago

There is no stealth in space. https://www.projectrho.com/public_html/rocket/spacewardetect.php#nostealth https://www.projectrho.com/public_html/rocket/spacewardetect...

perihelions 2y ago
That page isn't really responsive to my comment. I'm not sure what point you're trying to make! Of course if you point a directional radio transmitter at an observer, you are not being stealthy, to that observer. Of course if you power up a 100 gigawatt incandescent rocket motor, you're loudly advertising your presence. (No different than a stealth aircraft using afterburners—they don't). Stealth spacecraft would necessarily avoid doing that. Stealth spacecraft could, to highlight one option from a large decision space, consider cryogenic, cold-gas thrusters with invisible output plumes and zero infrared emissions.
- nradov 2y ago
  Did you even read the whole page? Using cold gas thrusters doesn't solve anything, especially not if you have a crew on board.

ashoeafoot 2y ago

The goal of actual spacewar is to make a auto railgun bullet hell with near c pellets from outside the system, then move in with railgun drones to lure your opponent into the rain or redirect the rain were the opponent will be forced to go. not to dissimilar to 3d flak.