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126 points voxadam | 5 comments | | HN request time: 0.001s | source
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baxtr ◴[] No.44054307[source]
Instead of petawatts I’d love to hear what it can destroy.

I imagine a scale like:

1: Mosquito

10000: Planet (Death Star)

replies(1): >>44054678 #
vlmutolo ◴[] No.44054678[source]
To kill a mosquito, you need "a few tens of millijoules, delivered within a few milliseconds" [0], so let's say 10W. To destroy the Earth (so that it turns into scattered dust and never reforms) you need about 10^32 J [1]; if we assume this is applied over maybe 100s, the laser would be 10^30W.

So the log10 scale goes from 1–30, where mosquitos die at 1 and the Earth dies at 30. The 2 PW in the article is about a 15.3. The Vulcan 20-20 project (set to complete in 2029) will register at about 20PW, or a 16.3 on the mosquito-Death Star scale [2].

So on a log scale, we're over halfway to building the Death Star.

[0]: https://spectrum.ieee.org/backyard-star-wars

[1]: https://www.scientificamerican.com/article/how-much-energy-w...

[2]: https://news.sky.com/story/worlds-most-powerful-laser-to-be-...

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1. Dylan16807 ◴[] No.44056478[source]
If we're comparing lasers that go for seconds and lasers that go for femtoseconds, I think measuring watts is way too misleading.

Measured in simple joules, mosquito is .04, earth is 10^32, and this laser is 50.

If we make a joules version of the 1-30 scale, the laser in the article would only score a 4.

replies(2): >>44056970 #>>44065977 #
2. Hikikomori ◴[] No.44056970[source]
So I could kill all the mosquitoes in my yard in one pulse with this laser.
replies(1): >>44057144 #
3. Dylan16807 ◴[] No.44057144[source]
If they get close enough together for that pulse to hit them all.
replies(1): >>44057723 #
4. MyPasswordSucks ◴[] No.44057723{3}[source]
Just send me out there and aim the pulse at the one spot in the middle of my back I just can't quite reach.
5. vlmutolo ◴[] No.44065977[source]
For sure; using total energy delivered makes a lot more sense. But then I think it would be better to use whatever tool humanity has that delivers the max total energy; let’s say Tsar Bomba.

Let’s say the mosquito is 1 again, so Death Star is 34. Tsar Bomba would be about 17.3. Over halfway again!

It’s kind of surprising that our max power output and max energy output are about the same on these scales.