火星上空的火卫一
2023年7月31日 Phobos over Mars Image Credit: ESA, DLR, FU Berlin, Mars Express; Processing & CC BY 2.0 License: Andrea Luck Explanation: Why is Phobos so dark? Phobos, the largest and innermost of the two Martian moons, is the darkest moon in the entire Solar System. Its unusual orbit and color in […]