Solar System & Layers of the Earth

• ​Population I:

  Young stars with high metallicity, found primarily in the galactic disk, including our Sun. 

  
  

• Population II:

  Older stars with low metallicity, found in the galactic halo and globular clusters. 

• Population III:

  The very first stars formed in the universe, with extremely low metallicity, not yet directly observed. 

​Categories of Stars

Multiple Choice

What is a nebula?

• A nebula is a cloud of gas and dust in space.
• A nebula is a type of star.
• A nebula is a planet in the solar system.
• A nebula is collection of gas dust, and planets.

​Types of graphs and their usefulness

Line Graphs- Track changes over time (independent variable is always on the X-axis
Bar Graphs- Compare different groups or track changes over time
Pie Charts- show distribution of a whole

Multiple Choice

Gravity is the force objects put on each other because of their ______.

• mass
• friendliness
• acceleration
• speed

​*Moon is thought to have been formed by a giant impact by Earth

​Asteroid belt separates the inner and outer planets

Multiple Choice

Which layer of the earth is primarily composed of solid nickel and iron?

• Inner core
• Crust
• Mantle
• Outer core

Multiple Choice

Which layer of the earth behaves like a fluid but flows over long periods of time due to high temperatures and pressure is known as:

• Mantle

• Crust

• Inner Core

• Outer Core