Galaxies Even though we won’t be around when M31 approaches, what will be the earliest effects of the collision on Earth, the Sun, and the solar system’s planets?
Science The current theory of lunar genesis says a Mars-sized object collided with Earth and ejected material that later coalesced into the Moon. Is it just by chance that the newly formed Moon adopted an orbit that coincides with the ecliptic plane?
Solar System Is there any evidence that Earth’s magnetic poles (or any other planet’s) have reversed? What would cause such a reversal?