undefined | Better HN

0 pointsgpderetta3mo ago0 comments

I doubt a MW laser can reliably intercept a reentry vehicle. A lot of energy is lost through the atmosphere when intercepting a warhead in space, from a land based laser. Once it reenters the atmosphere there might not be enough time. You also need to burn through the heatshield that the warhead is equipped with for reentry.

Even if you can can deliver enough energy for long enough, there is no fuel to burn and it might not be easy to detonate or disable the warhead.

For ICBMs, one idea was to use orbital, nuclear powered lasers to hit the missile on the boost phase.

But that's very much not near-future.

Lasers might still be useful for rockets, drones and cruise missiles of course.

0 comments

2 comments · 2 top-level

O3marchnative3mo ago

> For ICBMs, one idea was to use orbital, nuclear powered lasers to hit the missile on the boost phase.

Author here. Thank you for your insight.

I took some time to read about the recently proposed "Golden Dome" defense system, and what you laid out seems to be the end goal [0]. It's difficult to tell how realistic this actually is. The size of the constellation of satellites needed seems prohibitive, to say the least.

[0] https://armscontrolcenter.org/fact-sheet-golden-dome/

[1] https://www.defenseone.com/ideas/2026/02/space-based-interce...

Voultapher3mo ago

I get the impression you didn't read the linked post. It goes into the details, atmospheric absorption for different wavelength, weather conditions, tracking time, interception time based on warhead hardness ratings and many more details. It's paper based, so in practice it will be more complicated and there are things it will have missed, and things we don't even know yet as being operational challenges for such systems. At the same time, it does present a compelling narrative and I'd much rather discuss individual assumptions or sources than dismiss it entirely based on a gut feeling.

j / k navigate · click thread line to collapse