太阳系的演化.ppt

Lecture 1 太阳系的演化?太阳系一些基本观测事实?太阳系的动力学过程?太阳系形成模型?进一步的检验和太阳系探测计划太阳系天体行星 s : the big bodies orbiting the Sun 矮行星 dwarf s : can have their own moons but not massive enough to scatter other objects 卫星 Satellites . moons: variously sized objects orbiting the s 小行星 Asteroids : small dense objects orbiting the Sun, 10,000 in the main asteroid belt between the orbits of Mars and Jupiter, and 35,000 Kuiper Belt (30-100AU) objects greater than 100 km in diameter ets : small icy objects with highly eccentric orbits 8 s: Mercury, Venus, earth, Mars, Jupiter, Saturn Uranus, Neptune 5 known dwarf s: Ceres (main asteroid belt) , Pluto, Eris, Makemake, Haumea (Kuiper belt), but dozens to hundred to be discovered 146 moons+21 waiting for confirmation, none/few around rocky s, 50 moons around Jupiter the systems of moons can be divided into regular objects (spherical) with direct orbits versus irregular objects with eccentric orbits Composition of Solar System in mass Sun: % s: % Comets: % ? Satellites: % ? Minor s: % ? Meteoroids: % ? ary Medium: % ? Inner solar system Orbit of s, ets: white arrows Asteroids: yellow dots revolve in the same direction as Sun, separate orderly , Inner s lie on a thin plane Asteroids have larger orbit inclinations to eclipse outer solar system ? Neptune 之外很多小天体-- Kuiper-Belt ? Pluto 和其他一些天体轨道穿越 Neptune 轨道. 这些天体形成一族 2:3 plutinos ?短周期彗星外缘与 Kuiper- Belt 相接 Pluto 轨道平面相对黄道倾斜 17度; distant solar ets are not confined to the Ecliptic plane, while asteroids almost do