1. Astronomy

2. The Universe
The universe is defined as everything that physically exists: the entirety of space and time, all forms of matter, energy and momentum.

3. How our Universe Formed
Theory of how the universe formed called the Big Bang Theory
Big Bang Theory – the universe formed from a massive expansion approximately 14 bya
The Universe is expanding and the visible edge is about 13.7 billion light years away

4. The universe began billions of years ago as a tiny dot that exploded into today’s huge system of stars and planets.

7. Support for the Big Bang Theory
Red shifts
Cosmic background radiation
Radio signals coming from every direction in space.
Believed to be created by the big bang explosion.

8. 1929 – Edwin Hubble found that the universe is expanding

9. Hubble’s Law: the more distant galaxies have greater red shifts, therefore they are moving away at faster speeds.

10. Hubble’s Law

11. Note: Our solar system is part of a bigger system called a galaxy
Note: Our solar system is part of a bigger system called a galaxy. Our galaxy is part of a bigger system called the universe
Milky Way Galaxy…spiral shaped!

12. The universe is made up of galaxies.
Galaxies are held together by gravity.
The galaxy that we are in is the Milky Way Galaxy.
Types of Galaxies– spiral, barred, elliptical, irregular

13. Spiral - Milky Way Galaxy
The Milky Way galaxy contains more than 100 BILLION stars

14. Barred – NGC1300 Galaxy

15. Elliptical – NGC1316 Galaxy

16. Irregular – Large Megallanic Cloud
This is the CLOSEST galaxy to us

17. Solar System
Solar systems - consist of at least one star and include all bodies that revolve around it in the stars gravitational pull.

18. Pluto
Neptune
Uranus
Mercury
Saturn
Jupiter
Mars
Earth
Venus

19. So, how did our Solar System form?
The Nebular Theory – explains that solar system was formed from a rotating disk of dust and gas
Formed ~4.6 bya

20. 1.Solar System began as a giant ball of dust and gases (after the Big Bang)
Cloud flattened as it spun
around, forming an accretion disk.
►Sun formed in the middle from all the heat in the middle of the disk
Cooling of the disk caused small shapes to form
4. These cool forms combined to
make the 4 SOLID inner planets
The lighter material combined
farther away, forming the 4
GASEOUS outer planets

22. End of Day 1

23. The Earth moves in 3 ways The Earth: 1.Rotates (Rotation) 2.Orbits
3.Revolves (Revolution)

24. The earth rotates on its axis
Rotates = spins.
The earth makes 1 full rotation every 24 hours.

25. The axis always points towards the North Star.
The axis of the Earth is tilted at an angle of 23.5 degrees.
The axis always points towards the North Star.

26. We have day and night because of the Earth’s rotation.

27. The Earth also revolves around the sun in an elliptical orbit.
The earth makes one full revolution around the sun every days days = 1 year