Posts by HDE 226868
Use chicken manure. Other animals, besides livestock, also produce good manure, with different qualities. Now, not all manures are created equal; they differ in composition, volume, and production...
Avoid helicopters and airships. Try the WC-130 or WP-3D. First, airships are not fantastic choices for maneuvering in high winds. Helicopters are bad enough, but airships are large and slow, meani...
Look at Earth's biomes! When it comes to life and everything that comes along with it, we only have one data point, our own planet. Climate modeling is . . . hard. Really hard. When we're talking ...
Yes, and the planets can orbit in the habitable zones. This page gives a long list of planets in these S-type orbits, and states For a few systems (2 so far), there are planets orbiting each m...
The answer to your question, regrettably, is no, and the counterargument is a classic one. The pole is composed of atoms and molecules and particles; it isn't one giant indivisible object. Those ...
1. Orbit a high-mass planet In the Solar System, two moons are covered with ice and have subsurface oceans: Europa and Enceladus. Europa orbits Jupiter; Enceladus orbits Saturn. In the case of the...
Option 1: Continuous spectrum Your first choice would be to recreate the black body spectrum of the star. For a black body at a temperature $T$, the intensity $J(\nu)$ is $$J(\nu)=\frac{2h\nu^3}{c...
Why are transits so rare? Essentially, you want a low relative orbital inclination. A body's orbital inclination is the angular difference between its orbital plane and a reference plane. In the ...
Yes. There are sharks that live quite deep in the ocean; the goblin shark and frilled shark, for instance, have been known to live over 1,000 meters below sea level (Wikipedia claims great whites ...
Not for a planet, but for a smaller body. Massive bodies are in hydrostatic equilibrium. Gravity pulls them into spheres, eliminating most non-negligible variations from perfect roundness. Obvious...
Let's first think about what causes solar flares. The processes behind them are not substantially well-understood, but we do have some ideas. Magnetic reconnection is one possibility. Essentially, ...
The answers so far have assumed that the galaxy in question is a spiral galaxy - and if we're talking about the Milky Way, then that's all well and good. But galaxies are pretty diverse, both in sh...
Anywhere from ancient times to the present. Question 1: Is there anything there? (answered pretty quickly) Sunspots, for instance, were first observed by the Chinese in 364 B.C., two millenia bef...
Yes. For large animals, octopuses are a possible source of inspiration. They have neurons in their arms, which lets them have a very large brain-to-body ratio. This does let their arms move withou...
The idea of an ocean planet isn't too far-fetched. There are several moons in the Solar System - Enceladus and Europa, for instance - that have subsurface oceans. If the ice covering their surfaces...
There will be little difference. The lower atmospheres are the same. Let's assume that the atmospheric pressure, $P$, follows a simple exponential scale height model: $$P=P_0\exp\left(-\frac{z}{H}...
Try thermosynthesis. Thermosynthesis is a hypothetical mechanism, usually applied to the RNA world theory for the rise of life on Earth. In a nutshell, it states that an organism could function as...
Let's look at some key Jovian atmospheric characteristics: Density at $P=1\text{ bar}$ (i.e. the surface): $\rho_J=0.16\text{ kg m}^{-3}$ Temperature at $P=1\text{ bar}$: $T=165\text{ K}$ Mean mo...
You could use a large mid-ocean ridge, like the Mid-Atlantic ridge, and then play around with sea levels. Mid-ocean ridges occur at (divergent) plate boundaries, and can be thousands of kilometers ...
Many creatures - humans among them - have binocular vision, where two eyes side by side allow good depth perception. There are quite a few other advantages over one eye, including a larger field of...
I read through the discovery paper (Adriani et al. (2011)) about antimatter in Earth's Van Allen belts, and I just want to lay out a few points before we begin: The antimatter in the Van Allen be...
Basic characteristics The system you're describing here may be a contact binary, where the two stars have come close enough to actually touch. These systems may actually be stable for millions (or...
This question is inspired by Green's Volcanoes in Orbit! The premise is that there is a 50-mile-high shield volcano (again, let's ignore the height implausibility) with a slope of about 2-3 degrees...
What we're concerned with here is the eruption column and subsequent plume arising from the volcanic eruption. This is a shield volcano, so it's not going to erupt a la Mount St. Helens; rather, it...
Use a chain of ships. I'm imagining a pyramid setup, in a sense. Take $n$ ships. Send out the first one, of relatively low mass - Ship $1$. Then send out Ship $2$. Ship $2$ is now directly propell...
