1. EARTH’S PLACE IN THE UNIVERSE
A journey through the universe at the speed of light: 300,000 km/sec.
Earth is 150,000,000 km from the sun = 1 astronomical unit.

2. Stop One-

3. STOP 1: YOU HAVE TRAVELED 8 MINUTES SINCE LEAVING EARTH.
How many planets are 1 AU or less from the Sun?
3: Mercury, Venus, Earth.
Would all planets be on the same side of the Sun as Earth is?
No.

4. Stop Two-

5. STOP 2: YOU HAVE TRAVELED 14 HOURS SINCE LEAVING EARTH.
What does 100 AU mean?
100 AU x 150,000,000 km/AU =
15 billion km.
If you are looking down over the north pole of the planets, in what direction would you expect them to be moving around the sun?
Counterclockwise.

6. Stop Three-

7. STOP 3: YOU HAVE TRAVELED 0. 16 YEARS (58 DAYS) SINCE LEAVING EARTH
STOP 3: YOU HAVE TRAVELED 0.16 YEARS (58 DAYS) SINCE LEAVING EARTH. 1 Light Year = 63,240 AU
How many kilometers are in 1 light year?
300,000 km/sec x 60 sec/min x 60 min/hr x 24 hr/day x 365 day/year =
9.5 trillion km.
How far are you from Earth in Kilometers?
.16 LY x 9.5 trillion km/LY =
1,517,760,000,000 km.

8. Stop Four-

9. STOP 4: YOU HAVE TRAVELED 16 YEARS SINCE LEAVING EARTH.
In AU’s, how far are you from Earth?
16 LY x 63,240 AU/LY =
1,011,840 AU.
Sirius is 8 light years from Earth. How long would it take for light from Sirius to reach Earth?
8 years.

10. Stop Five-

11. Stop Five-

12. STOP 5: YOU HAVE TRAVELED 1600 YEARS SINCE LEAVING EARTH.
What constellations shown in the star chart are the same as those you would see 1600 light years from Earth?
Orion, the Pleides, Deneb, etc.

13. Stop Six-

14. STOP 6: YOU HAVE TRAVELED 160,000 YEARS SINCE LEAVING EARTH.
A galaxy has been described as an island universe. What does this mean?
Islands are surrounded by water like a galaxy is surrounded by open space.
Where do most of the stars seem to be concentrated in the Milky Way galaxy?
In the center of the galaxy.

15. Stop Seven-

16. Stop Seven-

17. STOP 7: YOU HAVE TRAVELED 16,000,000 YEARS SINCE LEAVING EARTH.
Andromeda is 2.2 million light-years from Earth. Astronomers study it through the light it emits. How long ago did that light leave Andromeda?
2.2 million years ago.
Studying distant galaxies is described as looking back into the past. What does this mean?
Since galaxies are so far away, observations are what they looked like when the light left them.

18. 3. You decide to pause on your trip to write a letter back home
3. You decide to pause on your trip to write a letter back home. When will your letter arrive if it travels at the speed of light?
16 million years from now.
4. How would you address your letter? What is your cosmic address?
Universe, Local Group of Galaxies, Milky Way, Orion Arm, Solar System, Earth, USA, California…