1. Astronomy

2. What do YOU know about the Universe?
DO NOW/Warm-Up
Answer Question:
What do YOU know about the Universe?
Discovery Education : A View of the Universe
Write Questions in Do Now Section of Binder Follow along by answering the questions as you watch the video
Title: Discovery Education : A View of the Universe
What is another name we can use to call the universe?
What can each point of light in the universe become?
What is the yellow star in the spiral galaxy orbited (circled) by eight planets called?
About how old is the universe? (

3. Day 1 Lesson Objective Today you will be able to:
Explain the origin of the Earth’s motion based on the origin of the galaxy and its solar system.
Recall Earth’s role in the hierarchy of organization within the universe and in the developmental continuum. (Universe is made of galaxies which are made of many stars. Some stars have planetary systems similar to our solar system. Earth is a satellite planet of one particular star.)

4. 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

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

7. Cosmic background radiation
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. The Expanding Universe
1929 – Edwin Hubble found that the universe is expanding
Estimated distances, relative brightness, Doppler red shifts

9. Dimmer galaxies had greater red shifts  farthest from Earth
Hubble’s Law: the more distant the galaxies have greater red shifts, therefore they are moving away at faster speeds.
Milky Way Galaxy…spiral shaped!

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

11. Hubble’s Law

12. Transitioning to Objective # 2
• Recall Earth’s role in the hierarchy of organization within the universe and in the developmental continuum. (Universe is made of galaxies which are made of many stars. Some stars have planetary systems similar to our solar system. Earth is a satellite planet of one particular star.)

13. 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 (Milky Way) is part of a bigger system called the universe
Milky Way Galaxy…spiral shaped!

14. Galaxies and Stars Galaxies – billions of star groups
more than 100 billion galaxies, each containing billions of stars
Milky Way Galaxy…spiral shaped!

15. 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

16. 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

19. Do Now What is the big bang theory?
What is some evidence to support the big bang theory?
What is a red shift and what does that tell us about distance of objects in space?
Explain in your own words what Hubble’s Law states. Hint: think about your lab from last class

20. Day # 2 Objective 3 &4 Today you will be able to:
• Explain planetary orbits especially that of the Earth, using Kepler’s laws.
• Explain relative motion of the Earth in the solar system, the solar system in the galaxy, and the galaxy in the universe—including the expanding nature of the universe; Orbital motion (Earth around the Sun- once/year, seasons depend upon an approximate 23.5 degree tilt); Rotation around our axis (day/night,)

21. Earth’s Role in the Solar System
The universe is made of galaxies which are made of many stars. Some stars have planetary systems similar to our solar system. Earth is a satellite planet of one particular star (our sun).

22. Three Ways in Which the Earth Moves
1.Rotates (Rotation)
2.Orbits
3.Revolves (Revolution)

23. Ways the Earth Moves Rotates = spins.
The earth makes 1 full rotation every 24 hours.
The axis of the Earth is tilted at an angle of 23.5 degrees.
The axis always points towards the
North Star

24. Ways the Earth Moves
We have day and night because of the Earth’s rotation.
Draw the picture below in your notes

25. Ways the Earth Moves
The Earth also revolves around the sun in an elliptical orbit.
The earth makes one full revolution around the sun every days. 365 days = 1 year

26. Kepler’s Laws
Provide Definition of Kepler’s Laws, Precession, Nutation and Barycenter.
Draw a picture illustration
Explain how you would act it out

27. How Earth’s Formation Affected Earth
Earth orbits the Sun following Kepler’s 3 laws of planetary motion
The path of each planet around the Sun is an ellipse
Equal areas are covered in equal time
The length of time it takes a planet to orbit the Sun is proportional to its distance from the Sun

28. Kepler (1571-1630) came up with these scientific laws and they are still used in Astronomy today!

29. 1st Law: Law of Ellipses
The path of the planets around the sun are elliptical in shape with the center of the sun being located at one focus
The shape of the ellipse is determined by the location of the two focus points!

30. 2nd Law: Law of Equal Areas
This law states that an imaginary line from the sun to a planet sweeps out equal areas in equal time intervals

31. Kepler’s 2nd Law of Planetary Motion

32. Are they the SAME?
The short wide glass is holding the SAME amount of water as the tall skinny glass!

33. Planet moves FASTER in orbit when CLOSE to the SUN, and SLOWER in orbit when FAR FROM the SUN
WHY?
GRAVITATIONAL PULL

34. Keppler’s 3rd Law

35. Kepler’s Three Laws of Planetary Motion (A Summary)
Each planet takes an elliptical path around the sun
Planets travel faster when they are close to the sun and slower when they are farther away from the sun
The amount of time needed for a planet to revolve around the sun is proportional to the the planet’s distance from the sun B C A

36. Precession
The direction this axis of a planet is pointing in will change, but the tilt will not change.
This will change the stars near the pole but will not change the seasons (as long as the angle of the tilt, 23.5 in the case of Earth, stays the same)

37. Precession Animation

38. Nutation
Nutation happens when the axis of a planet starts to wobble (do the wobble!)
The angle of the axis will change during nutation ½ degree one direction or the other
Nutation happens over the course of 18 years
Nutation is a direct result of the moon (or moons) of a planet

39. Barycenter
A barycenter is the point between two objects where they balance each other (For example, the middle balancing point on a scale).

40. Barycenter Example
For example, the moon does not orbit the exact center of the Earth, but a point on a line between the Earth and the Moon approximately 1,710 km below the surface of the Earth, where their respective masses balance.
This is the point at which the Earth and Moon orbit as they travel around the Sun

41. Do Now
Draw a picture of the Earth on it’s axis. At what degree is it tilted?
Describe Kepler’s first law.
What does the law of equal areas state?
Draw a picture depicting his 1st and 2nd law.
Describe Kepler’s third law.

42. Application and Critical Thinking Questions
In degrees, what is the tilt of the Earth?
Summarize and explain all 3 of Kepler’s laws of planetary motion into one or two sentences.
How does precession affect the Earth’s rotation and revolution?
Explain in your own words what nutation is .
Based on the concept pf barycenter, explain the evolutional relationship between the sun and the earth.

43. Exploring Orbits: Eccentricity Lab
Goal: To draw variously-sized elliptical orbits by changing the locations of the two foci points and then using that information to analyze the orbits of our solar system’s planets.
Video Demonstration:

44. Demo/Group Work Activity
What does eccentricity measure?
Ms. Sterling observed the orbital path of Mars. From the data she collected, she found the focal point length to be 10 light years and the major axis length to be 22.5 light years. Find Mars’ eccentricity based on her observations.
Planet X has an eccentricity of and Plant Y has an eccentricity of Using these measurements explain the paths of these planets around the sun.