1. Introduction to Astronomy & Tools of Science
(Power Point 01)

2. Student Learning Objectives
Compare and contrast the scale and dynamics of objects and systems in the universe.
Diagram your location in space
Write and interpret numbers in scientific notation
Define astronomical distance measurements
Apply the scientific method

4. What is our location in space?
We live on planet Earth
In the Milky Way Galaxy (1012 stars)
Part of the Local Group (Galaxy Cluster)
Within in the Virgo Supercluster
One tiny spot in the visible Universe

5. Sizes of Things Video https://www.youtube.com/watch?v=ilyrk_waIGw

6. What is Scientific Notation?
Multiples of 10
The number of multiples/divisions of 10 is indicated as a power.
Earth-Sun d = 93 x 106 miles
Blue Light l = 450 x 10-9 meters

7. Practice
Write 67,000 in scientific notation - Distance from center of galaxy to Sun
2) Write 1012 in standard notation - Number of stars in our galaxy
3) Write 3.5 x 10−14 in standard notation - A frequency of red light

8. What is the measurement system used in astronomy?
metric system
Each factor of ten difference results in a single move of the decimal.
Prefix
Power of Ten
Word
Mega
106
Million
Kilo
103
Thousand
Micro
10-6
One Millionth
Nano
10-9
One Billionth
Angstrom
10-10

9. Practice
1) Red light has an average wavelength of 650 nm. Is this a very small or very large number? 2) Distances to galaxies are measured in Mega-parsecs. This is (hundreds, thousands, millions) of parsecs. (choose one)

10. Astronomical Unit
1 AU
1.96 x 108 km
9.298 x 107 miles

11. Light travels 1 AU in about 8 Minutes
Light Year
A light year measures distance, not time.
The light-year (LY) is the distance light travels through a vacuum in 1 year.
Light travels 1 AU in about 8 Minutes

12. Parsec A parsec measures distance, not time! (“kessel run”)
1 AU
1´´
1/2´´
1 parsec
1º = 3600´´

13. Practice
What is the correct order from smallest to largest? 1 mile 1 pc 1 meter 1 LY 1 nm Earth’s Diameter 1 AU
1 pc
3.26 LY
206,265 AU

14. What is science?
Science is not simply a collection of facts, but rather an objective process of quantifying what we observe.
The outcomes of science are laws and theories with repeatable results.
Tested
Verified

15. Observe/Question  Hypothesize/Predict  Observe/Confirm  Theory 
How is science done?
Each scientist must be able to obtain the same results.
Example: Gravity
Observe/Question  Hypothesize/Predict  Observe/Confirm  Theory 

16. Questions to Consider
1) What do you think happens if scientists cannot obtain the same results? 2) Can the scientific method be used to answer all questions? 3) What is pseudoscience?

17. What is astronomy?
Astronomy is a science.
Astronomers study the universe and all objects contained within the universe.