Periodic Familes and MOY 02/07

Agenda:

1. Warm Up2. Correct quizzes3. 45 minutes for project4. HR Diagrams and MOY

review5. Light Years

Please pick up the warm up and answer the FIRST question

The EARTH is 93 Million Miles from the SUN.

Distances in our Solar System are measured in ASTRONOMICAL UNITS (AU).

IS A MEASURE OF

A LIGHT YEAR IS THE DISTANCE

LIGHT TRAVELS IN ONE YEAR!!!

Scientist use LIGHT YEARS because STARS are too far away from each other to use…

One LIGHT YEAR is

or

1 year 1 year 1 year 1 year 1 year

1 x 1016 1 x 1016 1 x 10161 x 1016 1 x 1016

Five Light Years = 5 x 1016 meters

43 Light Years from EARTH

It takes 43 (human) years for the light from

this star to reach earth!

•By the time you see the light 43 years have passed.•The light was created before most of your parents were born.