Re:Caltech Researchers Find Evidence of a Planet Beyond Pluto
by jessriedel on Wednesday January 20, 2016 @03:17PM
(#10941011)
Shouldn't it be fourth power of distance (N^4) not sixth? For objects beyond the diffraction limit (i.e., objects whose radius cant be resolved), visibility is determined by total light reaching the observer. Angular size isn't important. (And, if anything, diffusing a fixed amount of light over a larger solid angle makes it harder to see.)
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Re:Caltech Researchers Find Evidence of a Planet Beyond Pluto
by bzbarsky on Wednesday January 20, 2016 @03:50PM
(#10941235)
If you're just trying to see all the objects, then yes, N^4. But if you're trying to figure out whether they're planets, you need to either resolve disks or take multiple observations to observe motion. I don't have a good feel for how the latter scales with N in practice...