Astrophysics and Cosmology
完成条件
按索引浏览词汇表
特殊 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | 全部
U
UltravioletElectromagnetic radiation with wavelengths shorter than visible light. | |
Universal gravitational constantthe constant used in Newton's Law of Universal Gravitation. | |
UniverseEverything that exists, including all matter, energy, space, and time. | |