5 ms·
Moreover, to keep the beam tightly focused on one probe at a time would require an adaptive optics system that compensated for atmospheric turbulence — somethin
by NoGravitas 11y ago
Moreover, to keep the beam tightly focused on one probe at a time would require an adaptive optics system that compensated for atmospheric turbulence — something astronomers know how to do over a span of 10 meters, the size of a big telescope mirror now, but not over a mile.
Would it be easier just to put the lasers on the moon?
- oabm 11y agoIt might be easier to fire the lasers from the moon, but getting the lasers to the moon would be a huge pain.
- stdgy 11y agoNot to mention supplying these hypothetical moon lasers with enough power to blast these mini-probes into another star system.
- Zikes 11y agohttps://en.wikipedia.org/wiki/Helium-3 https://en.wikipedia.org/wiki/Helium-3 ought to do the trick.
- Zikes 11y agoI'm a bit surprised at the downvotes. I'm no scientist, but I meant this suggestion in earnest. As far as my layman's knowledge goes, I've always understood the Moon's He-3 reserves to be a "vast, as-yet-untapped power resource".
- marcosdumay 11y agoPeople have to learn how to harvest power from fusion before.
- ars 11y agoYou know how they have chemically pumped lasers? So it would be awesome to directly pump the laser from H3 fusion. H3 fusion is actually very easy - I think we could do it today. We just don't have a readily available source of H3 for fuel.
- Ankaios 11y ago3He fusion is easy—you can do it in a garage with some hacked-together equipment. However, 3He fusion with net power output is exceptionally hard, even with complete disregard to cost. Much harder than deuterium-tritium fusion. We don't know how to do it yet.
- ars 11y agoThanks for the correction. Seems the rosy predictions I remembered are not accurate.
- a3n 11y agoYeah, but then we'd be on the Moon. Again.
- imaginenore 11y agoOr just in orbit. Way easier, no need to overcome moon's gravity.
- jim-greer 11y agoHow could you store enough power in orbit to fire it?
- mturmon 11y agoWell, you could use your handy 200 GW solar array. With perfect conversion, and ~1300 W/m^2, you'd need to get your 12km x 12km panel array pointed consistently at the Sun.
- imaginenore 11y agoYou actually don't need anything crazy like that, as you don't need continuous 200GW forever, only for 2 minutes. You just need enough energy storage so you "only" need to store 6.6 gigawatthours. Lithium ion battery energy density is 265 watthours per kg. So you will need 24.9 million kg of batteries. Or 24.9 thousand tons. It's a lot, Tesla factory makes more per year.
- schwarrrtz 11y agoThe moon is really dusty, which might be problematic. https://en.wikipedia.org/wiki/Lunar_soil#Moon_dust_fountains_and_electrostatic_levitation https://en.wikipedia.org/wiki/Lunar_soil#Moon_dust_fountains...
- gene-h 11y agoHowever, this is much clearer than firing said lasers from under the atmosphere. While charged dust is a problem for the laser equipment itself, this can be mitigated with special dust attracting equipment. Getting the lasers to the moon would be a bigger problem.