1. Intro to Astronomy Unit
Early Astronomers
Intro to Astronomy Unit

2. Ancient Greeks Biography Aristotle (384-322 BC) Major Contributions
Proved that the Earth is round using math and observations.

3. Claudius Ptolemy Biography Greek Lived ca. AD 83-168
Major Contributions
Created the Geocentric model of the solar system in which the Earth was the center.
Biography
Greek
Lived ca. AD

4. Nicolaus Copernicus Biography 1473-1543 From Poland
Major Contributions
Earth as a planet
Model of the solar system with the sun at center called the Heliocentric model.
Proved that Earth rotates

5. Johannes Kepler Biography 1571-1630 Danish Brahe’s assistant
Major Contributions
Discovered 3 laws of planetary motion:
Planet’s orbit is an ellipse (oval) shape
The planets move faster when nearer the sun and slower when farther away
A planet’s orbital distance determines its distance from the sun
Defined the term astronomical unit as the average distance between the Earth and the sun (approximately 150 million km)
Biography
Danish
Brahe’s assistant
Mathematical
*New astronomy*

6. Galileo Galilei Biography 1564-1642 Italian Major Contributions
Galileo used a telescope to make better observations.
Four “satellites” or moons orbiting Jupiter
Planets are circular disks, not just points of light
Venus has phases just like the moon
Biography
Italian

7. Sir Isaac Newton Biography 1642-1727 English Major Contributions
Formulated the law of universal gravitation saying that all objects have gravity between them.
Explained the laws of inertia and gravity.
Inertia says that an object in motion will stay in motion till acted on by another force.
Biography
English

8. Contemporary Astronomers
Major Contributions
Explained that the universe was and still is expanding
Has a telescope that orbits in space named after him. The Hubble Space Telescope
Theorized the existence of black holes.
Edwin Hubble
Biography
Born: 11/20/1889
Died: 9/28/1953
American
Stephen Hawking
Born:1/8/1942
British

9. Geocentric Model/Earth Centered

10. Heliocentric Model/ Sun Centered

11. Geo and Heliocentric
Geocentric meaning Earth Centered was created by Claudiaus Ptolemy. He thought the earth was the center of everything in the Solar system.
Heliocentric meaning Sun Centered was created by Nick Copernicus and he thought and proved that the sun was the center of the solar system and every thing revolves around the sun.

12. Astronomical Unit
The time it takes for light to travel from the sun to earth is 1 AU. ABOUT 150 MILLION KILOMETERS…….
Light Year- The distance light travels in 1 year
Light Minute- The distance light can travel in 1 minute
Light Hour- The distance light can travel in 1 hour.

13. The Big Bang Theory
Big Bang Theory is where a nebula cloud of rotating gases and rock; condensed, heated then cooled and collapsed. As a result this created our galaxy and solar system.

14. Order of Formation
Big Bang
Galaxies
Solar system
Sun
Earth

15. Big Bang Order of Formation
As this cloud of gases and rock condensed and exploded, several things formed.
The first thing that formed was the different Galaxies. There are 3 types of galaxies. Our Galaxy is the Milky Way. Yummmmm!
The second thing that formed was the Sun. It provided heat for the planets, including earth.
Next and last they earth began to take shape, form and grow.

16. Types of Galaxies

17. What is a galaxy?
A galaxy is a huge cluster of stars, dust, and gas held together by gravity.
Large galaxies have more than a trillion stars while small galaxies have fewer than a billion.
Astronomers believe that there are billions of galaxies in the universe.

18. Basic Types of Galaxies
Spiral
Irregular
Elliptical

19. Spiral Galaxy Shaped like pinwheels
Sweeping “arms” made of gas, dust, and younger stars, rotate around the galaxy’s center called a bulge.
The bulge is a dense group of old stars
Our Milky Way Galaxy is a Spiral Galaxy.

20. Milky Way Galaxy
Our solar system is located on one of the spiral arms called the Orion Arm.
All of the stars we see at night are part of the Milky Way Galaxy.

21. Elliptical Galaxies Among the largest galaxies in the universe
Looks like a snowball
Contains mostly older stars that rotate around the center of the galaxy in an unorganized fashion

22. Elliptical Galaxy

23. Irregular Galaxies Least common type of galaxy Smaller and shapeless
Contains very hot newer stars and older stars
May form when two galaxies collide

24. Irregular Galaxy

25. Gravity
Gravity is the force between all objects that pulls them together.
Gravity Keeps the planets in orbit around the sun. Gravity keeps you and all objects on earth.
2 factors affect gravity- Mass of an object and distance between objects.
For example- Mercury has more gravity to the sun than earth because the distance is shorter between them.

26. Inertia
Inertia is a law that states that all objects will stay in motion until stopped by another force.
For example- gravity holds the planets in orbit but inertia keeps the planets moving.
The moon has both gravity and inertia.

27. Our 8 Planets
Mr. Smith

28. The Sun Made of mainly gases.
Much larger than any planet in the solar system.
Creates the gravity needed to hold planets in orbit.
The sun is the only star in our solar system. All other stars are in our galaxy outside our main system.
As you look into the night sky, your seeing our galaxy and solar system.

29. Continued……Sun
The sun is made up of 6 parts; The Corona, Chromospheres, photosphere, Convective zone, radiative zone and the core.
When you look at the sun your seeing the Photosphere.
The Corona is the suns atmosphere
The Convective zone is where the gases circulate
The core is where the gases are burning

30. Continued……Sun Will the sun burn out or shrink?
Scientist have found out that the suns energy comes from nuclear fusion.
Fusion is the joining of two atoms to create energy.
The energy created from hydrogen atoms fusing creates helium atoms. It then gets sent into other layers and eventually reaches the surface in the form of light energy.

31. Sun

32. Mercury 1st planet from the sun Shortest revolution/year=88 earth days
Rotation/day=58 earth days
Rotates retrograde (clock wise)
Much smaller than earth and the smallest planet
Its atmosphere is made of Oxygen, sodium, helium
Mercury is a terrestrial planet
Terrestrial means the type of surface
Mercury has little to no atmosphere and manly composed of Oxygen, sodium and helium.
Temperature ranges from -297 at night and 872 degrees F during day.

33. Mercury

34. Venus- When a volcano meets a tornado!
2nd planet closest to the sun and the planet before earth.
Most like the Earth
Slightly Smaller than earth
Retrograde rotation- Counter clockwise
2nd fastest revolution of all planets
Covered by a layer of clouds that trap heat and covered by volcanoes.
Temperature=856 degrees F
Atmosphere made of carbon dioxide(soda’s)
Rotation= 243 earth days)
Revolution= 224 earth days/ 1venus year

35. Venus

36. Earth- The 3rd rock from the sun!
Most complex planet with every system- water, air, land and life.
5th largest in solar system
23 degree tilt on axis
70 percent of earth is covered by water
Mostly degrees
Atmosphere 78% nitrogen and 21% oxygen
3 layers of surface- Crust, mantle and core
Revolution= 365 days in
Rotation=24 hours
Prograde Rotation which means counter clockwise.

37. Earth and moon

38. Mars Often called the Red Planet, Mars means God of War
Known to have water in its polar area that is frozen.
Atmosphere made of Carbon Dioxide
Temperature ranging from -225 to 62 degree F.
7th largest planet
4th shortest year/4th shortest revolution around the sun. Takes 1.8 earth years.
Has the Largest Volcano in the solar system called Olympus Mons, 15 miles high and 400 miles wide
Rotation= 24 hr 37 min
Revolution= 1.88 earth years/ 1 mars year

39. Mars

40. Mars and its moons

41. Jupiter Jupiter’s name means, King of the Roman Gods
First of the Gas Giants and majority of the planet is made of gas/very little is solid.
The largest planet in the solar system
Rotation/day=9 earth hours
Revolution/year=11.8 earth years
Atmosphere made of Hydrogen and Helium
Has 28 moons. The 4 largest are called the “Galician Satellites” named after Galileo who found them.
318 times the size of Earth
Known for having “the Great Red Spot” which is a Hurricane on the surface of Jupiter.

42. Jupiter

43. Jupiter's moons

44. Saturn

45. Saturn’s Moons

46. Neptune

47. Neptune’s Moons

48. Uranus

49. Uranus Moon’s