1. The Solar System

2. THE UNIVERSE The universe is everything physical that exists in space.
The universe is made up of galaxies

3. The Sound of the Big Bang - Picture and Sound Clip - MSN Encarta
The Big Bang Theory suggests the universe began with a big explosion 15 billion years ago

4. 3 kinds of galaxies
irregular)

5. A galaxy is a collection of stars, dust, gas classified by its shape.
Spiral has a bulge in the dense center with arms extending outward
Elliptical is an egg shape with mostly old stars
Irregular lacks definite shape
Our solar system is in the Milky Way galaxy – a spiral galaxy

7. The Milky Way Galaxy is a disc about 100,000 light years across and around 2000 light years thick.

8. We measure the distance to planets in our solar system in astronomical units or light years
The distance from the sun to the Earth is called an Astronomical unit ( AU)
1 AU = 93 million miles or 150 million kilometers

9. A light year is a measure of distance, not time.
It represents how far light will travel in one year.
Light travels at about 300 million meters per sec
( 3 X m/s) “c”
1 light year = 9.5 X meters
It takes light about 5½ hours to travel across the solar system, so a light year is much bigger than this

10. Our solar system consists of the sun, eight planets, moons, dwarf planets, the asteroid belt, comets, meteors, and other debris.
The sun is the center of our solar system
ALL planets, asteroids, and comets orbit the sun.
The SUN is our closest star, it is over 100 times the size of the Earth
Moons orbit their planets

11. Our Sun is a normal main-sequence G2 star, one of more than 100 billion stars in our galaxy.
The next nearest star to us (apart from the Sun) is Proxima Centauri, which is about 4¼ light years away. Also known as Alpha Centauri

12. A planet is a celestial body that orbits the Sun… 8 or 9?????

13. The solar system Solar System Pictures My Very Educated Mother
Mercury Venus Earth Mars
The solar system
Solar System Pictures
Just Served Us Nine Pizzas
Jupiter Saturn Uranus Neptune Pluto

14. The Asteroid Belt
An area of 1000’s of asteroids in an elliptical orbit between Mars and Jupiter.

15. The Asteroid Belt separates the inner planets from the outer planets
Gaspar
Ceres, the largest object in the asteroid belt
is a dwarf planet
Asteroids that are on a collision course with Earth are called meteoroids.

16. Ceres (lower left) with the Earth and moon

17. This picture shows the sizes of the original three dwarf planets (Pluto, Ceres, and Eris) as compared to Earth. It also shows Pluto's large moon Charon (and its two small moons Nix and Hydra) and Eris's moon Dysnomia to scale. None of the distances between objects in this image are to scale. Images courtesy of NASA

18. What happened to Pluto??? READ ONLY:
In 2006 the International Astronomical Union (IAU) approved a new classification scheme for planets and smaller objects in our Solar System. Their scheme includes three classes of objects: "small solar system bodies" (including most asteroids and comets), the much larger planets (including Earth, Jupiter, and so on), and the new category of in-between sized "dwarf planets".

19. There are currently three official dwarf planets
There are currently three official dwarf planets. Pluto, formerly the smallest of the nine "traditional" planets, was demoted to dwarf planet status. Ceres, the largest asteroid in the main asteroid belt between Mars and Jupiter, was also declared a dwarf planet. The third and final (for now!) dwarf planet is Eris, an icy body on the edge of our Solar System that was discovered recently in Eris was temporarily labeled 2003 UB313 when it was first discovered, and given the nickname "Xena", before astronomers settled on the official name of Eris.

20. Both planets and dwarf planets orbit the Sun, not other planets (in which case we call them moons). Both must be large enough that their own gravity pulls them into the shapes of spheres; this rules out numerous smaller bodies like most asteroids, many of which have irregular shapes. Planets clear smaller objects out of their orbits by sucking the small bodies into themselves or flinging them out of orbit. Dwarf planets, with their weaker gravities, are unable to clear out their orbits.

21. Though there are just three dwarf planets now, their number is expected to grow. Scientists estimate there may be 70 dwarf planets amongst outer solar system objects that have been discovered already. Since we don't know the actual sizes or shapes of many of the objects we've found (because they are so far away), we can't yet determine whether they are actually dwarf planets or not. More observations and better telescopes will help us determine which other objects are dwarf planets. Astronomers speculate that there may be 200 or so dwarf planets out through the distance of the Kuiper Belt, an icy band of frozen planetoids on the edge of our Solar System.

22. The outer gaseous planets
Dist From sun
Period of Revolution
(1 year)
Rotation
(1 day)
Diameter
miles
atmosphere
Avg temp oK
# moons
Jupiter
5.2 au
11.8 years
9.8 hrs
88729
H, He, methane
ammonia
-120 63
Saturn
9.5 au
29.5
years
10 hrs
74600
-180 18
ring
Uranus
19.2au
84 years
18 hrs
32600
-210 15
Neptune 30 au
165
19 hrs
30200
-220 2

23. The inner terrestrial planets
Dist From sun
Period of Revolution
(1 year)
Rotation
(1 day)
Diameter
miles
atmosphere
Avg temp oK
# moons
Mercury
.4 au
88 days
59 days
3,030
N/A
452
Venus
.7 au
225
days
243 days
7,500
CO2
H2SO4
726
Earth
1 au
3651/4
24 hours
7,926
N, O
293 1
Mars
1.5 au
687 days
25 hours
4,222
-150 2