Posts by Ilmari Karonen
The 10% conversion efficiency mentioned in other answers is a decent rule of thumb — there's a lot of variation in the real world, but if you assume that the total prey biomass equals somewhere aro...
Hit it with a rock. A big rock. Something like Ceres might do, if you could somehow get it into an orbit that hits the moon with sufficient relative velocity. Alas, moving Ceres significantly fr...
From the viewpoint of evolutionary dynamics, the reason why very few species are both autotrophic (photosynthesizing) and heterotrophic (hunting / foraging on other living organism) at the same tim...
As far as dietary requirements go, there's absolutely no problem with giant spiders. They'd have essentially the same dietary needs as any other large predator, and so any environment able to supp...
If the ships really are travelling at the speed of light, using known physics (which is possible, sort of — see below), then they cannot communicate. The reason for this is time dilation: the clos...
I'm going to take a shot at near-term technology forecasting, and say that your time traveller's near future smartphone and laptop are probably charged over some version of USB (unless they're Appl...
The orbit you describe is typical for (moderately) long-period comets. Given the desired orbital period, we can calculate the semi-major axis of the orbit (which, for a highly elliptical orbit lik...
The Earth is round because it is in hydrostatic equilibrium: its gravity is strong enough, and the material comprising most of its bulk fluid enough, to make it flow into the shape that minimizes i...
As anyone who's studied inorganic chemistry knows, many salts of copper in the +2 oxidization state have colors ranging from green to a nearly black dark blue, including some remarkably intense sha...
One possibility could be wind-powered plants. A tidally locked planet with a stable atmosphere must necessarily have powerful winds transporting heat from the day side to the night side. (Ocean c...
