What’s in our Solar System?

Origin of Solar System

1.What’s in Our Solar System? 1 Star = the Sun 8 Planets= MVEM JSUN 5 Dwarf Planets= Pluto,Eris, Ceres, Makemake, Haumea * there may be many more 170+ Satellites=Moons 3,300 Comets (Kuiper Belt & Oort Cloud) 679,335 Asteroids (Eros) Millions of Meteoroids This is on p 99 in your notebook

2. How did our Solar System form?

A rotating cloud of gas and dust As it rotates, speed increases, disc collapses Accretion disc Star forms in center

3. What is the name of the theory?

Solar Nebula Theory Marquis Pierre Simon de LaPlace 1796

4. Why is it so hard to see planets beyond our SS?

They are close to stars and are small They are not bright They are far away

5. What do astronomers look for instead?

Astronomers look for planets as they are made They look for dust

6. Where is a good place to observe planets forming?

Orion’s Belt Disc of newborn stars in the Great Nebula

7. Describe 2 or 3 different kinds of planets.

A)Rocky or Terrestrial MVEM-small, dense, few moons, no rings B) Gas Giant or Jovian JSUN- huge, low density, many moons, ring systems C) Ice Worlds- Pluto & beyond

8. Why did the terrestrial planets end up with layers?

They had low gravity due to faster spinning and greater temperature Iron melted, sunk to center Created metallic core Lighter, rocky crust

9. How does their surface show the violence of the early SS?

Many craters Bombardment with debris left over from formation of SS

10. Why are the outer planets gas giants?

They formed beyond the “ice line” Molecules are slower and cooler Can hold on to more of them

11. What additional features do gas giants have?

Ring systems Many moons/satellites

12. What is Pluto?

Debris? Not a planet? A dwarf planet

13. What do astronomers expect other stars to do and other solar systems to be like?

They should form planets They should be like our solar system There should be billions of them