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
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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
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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
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Composition of Solar System in mass
Sun: %
s: %
Comets: % ?
Satellites: % ?
Minor s: % ?
Meteoroids: % ?
ary Medium: % ?
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Inner solar system
Orbit of s, ets: white arrows
Asteroids: yellow dots
revolve in the same direction as Sun,
separate orderly,
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Inner s lie on a thin plane
Asteroids have larger orbit inclinations to eclipse
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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
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Pluto轨道平面相对黄道倾斜17度;彗星更大.
但行星基本上在一平面
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distant solar system
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Comets are not confined to the Ecliptic plane, while asteroids almost do
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