1. Astronomy
Earth’s Place
in the Universe

2. Agree or Disagree?
Kepler discovered that the path of each planet around the sun is an ellipse.
The universe is made of galaxies, galaxies contain stars, stars may have planetary systems.

3. Famous Astronomers The Ancient Greeks Ptolemy Copernicus Brahe Kepler
Galileo
Newton

4. What is Astronomy?
The science that studies the universe that deals with
Properties of objects in space
Laws under which the universe operates

5. Famous Astronomers Ancient Greeks Ptolemy: 141 AD
Geocentric view (Earth centered)
Aristarchus (Ar is tar chus) – Heliocentric (Sun centered), retrograde motion
Ptolemy: 141 AD
Geocentric Model
Copernicus: – 1543
Earth was a planet
Model of the Solar System – Sun centered - heliocentric

6. Famous Astronomers Brahe: 1546 – 1601 Galileo: 1564 – 1642
Solar Eclipses
Geocentric universe
Galileo: – 1642
Telescope in 1609
4 moons of Jupiter
Sunspots
Newton: 1643 – 1727
Law of Universal Gravitation (Gravity)
3 Laws of Motion (Inertia, forces, action/reaction)
Supported Kepler
Father of calculus

7. Kepler: – 1630
3 Laws
1st law: The orbits of the planets are ellipses, with the Sun at one focus of the ellipse.
2nd law: The line joining the planet to the Sun sweeps out equal areas in equal times as the planet travels around the ellipse.
3rd law: The ratio of the squares of the revolutionary periods for two planets is equal to the ratio of the cubes of their semimajor axes.

8. History of the Universe
Big Bang theory
States that at one time, the entire universe was confined to a dense, hot, super-mass ball
About 13.7 billion years ago, a violent explosion occurred, hurling this material in all directions
Marks the beginning of the universe

9. Nebula Theory
Theory of how the bodies of our solar system evolved from an enormous rotating cloud called the solar nebula.
Made up of Hydrogen and Helium
Theory how the planets were formed 8

10. The Expanding Universe Theory
The Expanding Universe Theory, developed from the observed red shifts of celestial bodies, that the space between galaxies is expanding, so that they appear to recede from us at velocities that increase with their distance 9

11. Types of Galaxies Spiral
Disk-shaped with concentration of stars in the center and “arms”extending from the center
Contain old and young stars
Ex) Milky Way Galaxy
Elliptical
Round to oval in shape
Contain old stars
Ex) giant diffuse galaxies -largest
Irregular
No definite shape
Composed of young stars
Ex) Large and Small Magellanic Clouds (closest neighbor galaxies)

12. Agree or Disagree?
Kepler discovered that the path of each planet around the sun is an ellipse.
The universe is made of galaxies, galaxies contain stars, stars may have planetary systems.

13. End of day one!

14. Agree or Disagree
Revolution is the motion of a body along a path around some point in space.
Rotation is the turning, or spinning, of a body on its axis.
Barycenter is the center of mass between celestial objects.
Nutation is the wobble movement observed in precession.

15. Agree or Disagree
Precession is a slow movement in rotation of a body on its axis.
Earth’s revolution results in day and night.
One rotation of Earth around the sun is a year.
Seasons on Earth are due to the Earth’s rotation around the Sun.
Seasons of the Northern and Southern hemisphere are opposite.

16. Rotation The turning or spinning of a body on its axis
Causes day and night

17. Revolution Motion of a body along a path around some point in space.
Earth’s orbit is elliptical
Earth’s distance from the sun varies
Perihelion
Earth is closest to the sun
147 million km away
Occurs on January 3rd
Aphelion
Earth is farthest from the sun
152 million km away
Occurs on July 4th

18. Perihelion & Aphelion

19. Doesn’t affect the seasons
Precession
slight movement, over a period of 26,000 years where Earth’s axis points in different directions
Points to two stars
Polaris
Vega
Currently pointing to Polaris
Doesn’t affect the seasons

20. Nutation & Barycenter Nutation Barycenter
oscillatory movement of the axis of a rotating body or a wobble
occurs about 18.6 years
Barycenter
the point between two objects where they balance each other
the center of mass where two or more celestial bodies orbit each other
Barycenter website with animation

21. Seasons are caused by the tilting of the earth on its axis
When the Earth tilts towards the Sun = warmer seasons
When the Earth tilts away from the Sun = cooler seasons

22. How would you describe the Earth’s shape and appearance
How would you describe the Earth’s shape and appearance? What affects its shape? 17

23. End of Day Two! 18

24. Agree or Disagree
Tides are only caused by the Sun’s magnetic pull.

25. What are Tides? What causes Tides?
changes in elevation of the ocean surface
What causes Tides?
Gravitational forces of the moon and sun

26. Tidal Range Vertical distance between the high and low tides.
Vary from place to place and week to week.

27. Spring Tides Spring Tides Occur during the new and full moons
All gravitational forces are added together
Extreme high and low tides
High tidal range

28. Neap Tides Neap Tides During the 1st and 3rd quarters of the Moon
Gravitational forces are offset
Tidal range is the smallest value

29. Tides Tides occur 50 minutes later due to …
Rotation pattern of earth and moon.
This is known as a lunar day

30. Tidal Patterns Diurnal (daily) Semidiurnal (semi-daily) Mixed
one high and one low tide each lunar day. Occurs at Pensacola, Fl. And the Gulf coast.
Semidiurnal (semi-daily)
2 high and 2 low tides: each high and low tides are similar to the preceding high and low. Occurs in the Atlantic coast
Mixed
2 high and 2 low tides each day. Each high and low tides are different from each other. Occurs on the west coast.

31. End of Day Three! 25

32. Agree or Disagree?
Electromagnetic radiation includes gamma rays, X-rays, ultraviolet light, visible light, infrared radiation, microwaves and radio waves.
Nuclear fission and fusion are the same thing.
Sunlight is used in the process of photosynthesis for plants and other autotrophs to make energy.
Any living thing could exist without sunlight.

33. Light Electromagnetic radiation (spectrum)
Gamma rays - fastest
X-rays
UV rays
Visible spectrum (ROYGBIV)
Infrared waves
Radio waves – slowest
Electromagnetic Spectrum: The arrangement of these waves according to their wavelengths and frequencies

34. Light: Wave or Particle?
Wave: Found on Earth
Particle: Photons found in space

35. Spectroscopy
Study of the properties of light that depend on wavelength.
Visible white light passes through a prism producing the colors of the rainbow (ROYGBIV)

36. The Sun Solar Interior or Core
The Sun produces energy by a process known as nuclear fusion
Enough fuel to last another 5 billion years

37. Fusion VS. Fission Particles “Fuse” together to create energy
Found on the Sun and Stars
Particles split to create energy
Found in Nuclear Reactors splitting atoms to create energy

38. Energy from the Sun 6H2O + 6CO2 ----> C6H12O6+ 6O2
Solar energy into chemical energy through photosynthesis
Plants use sunlight to produce sugar through the actions of the chlorophyll
Chemical Formula
6H2O + 6CO2 ----> C6H12O6+ 6O2 30

39. How does the magnetic field protect us from harmful solar radiation rays?

40. End of Astronomy Unit! 32