1. SCIENCE 3-24-16

2. WARM-UP: What is our Galaxy called? What is our Galaxy called?

3. AGENDA: Notes Notes

4. DIFFERENT GALAXY TYPES: Elliptical

5. MILKY WAY GALAXY:

6. WHAT MAKES UP GALAXIES? 1. Gas Clouds {nebula} – dust and gas, some glow while others absorb light 1. Gas Clouds {nebula} – dust and gas, some glow while others absorb light 2. Star Clusters 2. Star Clusters Globular Cluster – are groups of older stars that looks like a ball. Globular Cluster – are groups of older stars that looks like a ball. Open Cluster – are groups of closely grouped stars. Newly formed ones might have bright blue stars. Open Cluster – are groups of closely grouped stars. Newly formed ones might have bright blue stars.

7. MODELS OF OUR GALAXY: Geocentric: the Earth is the center of the universe. The Greek astronomer Ptolemy discovered this theory with mathematical calculations. In this theory, the other planets and sun revolved around the Earth. Geocentric: the Earth is the center of the universe. The Greek astronomer Ptolemy discovered this theory with mathematical calculations. In this theory, the other planets and sun revolved around the Earth. Heliocentric: the sun is the center of the universe. The Polish astronomer Copernicus discovered this theory. In this theory, all the planets revolved around the sun. Heliocentric: the sun is the center of the universe. The Polish astronomer Copernicus discovered this theory. In this theory, all the planets revolved around the sun.

9. MISC. INFORMATION: Gravitational attraction increases as distance decreases. Mass and distance affect the gravitational pull between 2 objects. The umbra is the dark centralized shadow cast by planetary objects.

10. SMALL BODIES IN OUR SOLAR SYSTEM:

11. COMETS: A small body of ice, rock, and cosmic dust loosely packed together. A small body of ice, rock, and cosmic dust loosely packed together. “Dirty Snowball” “Dirty Snowball” These can sometimes have tails. These can sometimes have tails.

12. ASTEROIDS: Small, rocky bodies that revolve around the sun. Small, rocky bodies that revolve around the sun. Range in size. Range in size. Most orbit in the Asteroid Belt {wide region between the orbits of Mars and Jupiter}. Most orbit in the Asteroid Belt {wide region between the orbits of Mars and Jupiter}.

13. METEOROIDS: A small, rocky body that travels through space revolving around the sun. A small, rocky body that travels through space revolving around the sun.

14. METEORITES: A meteoroid that reaches the Earth’s surface without burning up completely. A meteoroid that reaches the Earth’s surface without burning up completely.

15. METEOR: A bright streak of light that results when a meteoroid burns up in Earth’s atmosphere. A bright streak of light that results when a meteoroid burns up in Earth’s atmosphere.