Our Solar System It's nice and all, but…..

Each planet is about twice as far from the Sun as the planet before it.

Metals will consense closer to the Sun, ices and gases can only form much farther out.

The orbits of the planets are nearly circular.

The orbits of the planets all lie in nearly the same plane.

The planet's orbital direction is the same as the spin of the Sun.

Moons orbit around planets, the same direction that planets orbit the Sun

Inner planets have higher density than the outer planets.

What does the moon have to do with it?

Asteroids, and asteroid belt will have many of the properties of the planets.

Comets are cold, old and bold. Orbits are highly ellipitcal

Things that can go wrong. 1.Planets collide 2.Not enough water 3.Too much water 4.Nearby exploding star 5.Moon has too much pull 6.Moon does not have enough pull 7.Nearby planet too big 8.Too alone 9.Too big of star 10.Too small of star 11.And on and on and on………..

We started out in a Nebular Cloud

Why would the cloud condense? Gravity? _____________________________________________________ Cold? _______________________________________________________ Supernovae ___________________________________________________

Why would the cloud condense? Gravity? ____Gravity would pull the cloud together, but only if nothing held it apart. Cold? ______The cold of icy space would condense the gas, except that as the gas came too close together, it would heat up, and push the cloud apart. Supernovae ___________________________________________________

Why would the cloud condense? Gravity? ____Gravity would pull the cloud together, but only if nothing held it apart. Cold? ______The cold of icy space would condense the gas, except that as the gas came too close together, it would heat up, and push the cloud apart. Except that dust (.001mm big) would shield the cloud from Sun's rays, and radiate energy away. Supernovae ___________________________________________________

Why would the cloud condense? Gravity? ____Gravity would pull the cloud together, but only if nothing held it apart. Cold? ______The cold of icy space would condense the gas, except that as the gas came too close together, it would heat up, and push the cloud apart. Except that dust (.001mm big) would shield the cloud from Sun's rays, and radiate energy away. Supernovae ____A large explosion could crush the cloud together. Like two hands.

The dust particles begin to accrete.

These is a limit to how big plantisimals can get, because of collisions. The rich get richer, the poor get poorer.

A large cloud of interstellar gas exists. 1.The cloud begins to collapse under the force of gravity, helped along by a.Dust keeping radiation out b.A supernovae to push it together 2.The cloud spins faster and faster as it collapses, because of the conservation of momentum. 3.Dust particles begin to accrete, or clump together. a.Static electricity at first holds them together. b.Large Plantisimals form, smaller ones are destroyed. 4. The system differentiates a.More dense material falls to the center b.Elements with high melting points condense

SECTION 29.4 Formation of Our Solar System 1. Gas and dust from which stars and planets form ____________ 2. Rotating disk of dust and gas that formed the Sun and planets ______________ 3. Solid bodies hundreds of kilometers in diameter that merged to form the planets ________ 4. Believed to be the first large planet to develop ________________ 5. One of the first elements to condense in the early solar system ______________ 6. Lacking in satellites because of proximity to the Sun _____________________ a. inner planets b. tungsten c. planetesimals d. solar nebula e. interstellar cloud f. Jupiter Complete each statement. 7. Asteroids orbit the Sun and range from a few kilometers to about ______ kilometers in diameter. 8. Most asteroids are located between the orbits of _________________ in the asteroid belt. 9. Asteroids are thought to be _____________ that never formed planets. 10. A meteoroid is a broken fragment of an asteroid or other _________________ material. 11. A meteor is a meteoroid that ____________ Earth’s atmosphere. 12. A large meteorite will cause an impact crater when it collides with Earth, that is about _______ the diameter of the meteorite itself. 13. As the gas and dust compressed under ______________, it began to spin _______________. 14. The density of the inner planets is ______________ than an average, and the density of the outer planets is ________________. 15 The gas giants are on the “outer side” of the __________________. 16. An orbiting celestial body that is a few hundred kilometers across is called a _____________.