1. There are many sources of light!
What is Light?
There are many sources of light!

2. SOLAR ECLIPSE

3. Do you know some examples of light?
Light sources (something that makes light)

4. Energy and Light Energy: the ability to do work
Light is ENERGY we can SEE
LIGHT ENERGY can change into HEAT ENERGY which can be used for work.

5. Light From Nature Natural Light: Light from nature
What can you think of?
The SUN!
Lights our world and warms it
We could not exist without the sun (plants, cold, darkness)

6. The Sun
The Sun is a star!
It’s the closest one to us so we get most of our light and heat from the Sun and not other stars (which are too far away!)
How important is the sun really?

7. Bill Nye and Solar Power

8. We see the sun everyday and we know it’s a big star with lots of energy but how much energy does it really have?
Solar Magnifier Video

9. The Moon Sometimes at night, the moon helps us see.
BUT the moon doesn’t make light
The Sun’s light bounces off the moon and makes it look like the moon is shining.

10. More Natural Light

11. Natural Light Natural light is really important to humans
But we can’t control them
We can’t turn the Sun on and off when we want to
Some of the animals that we saw before use bioluminescence to survive (communication, attract food)

12. Artificial Light A long time ago, humans only had natural light
How would their lives be different?

13. Artificial Light: Fire
Humans learned how to control natural light sources
They found out how to make fire!
They used fire to keep warm, cook with and also do things after the Sun went down

14. Fire
People learned they could burn other things than wood to make light
Examples?
Wax – Candles
Oil – Lamps
Chemicals - Sparklers

15. Artificial Light Artificial: Made by humans
Artificial Light: Light made by humans
Most are made by electricity
This is another type of energy
Artificial light is easy to control because they can be turned on and off with a switch

16. Bouncing Light? We talked about sunlight bouncing off the moon
Artificial light bounces too!
The reason we see road signs is because light from the car or streetlights bounces off the sign!

17. $ The Costs $ Natural Light is always free!
Artificial Light always costs money!
Buying lamps, electricity, oil, batteries, flashlights
Even candles, sparklers and reflective clothing
We should conserve money and energy by shutting off artificial lights when we can!
OPEN A WINDOW! 

18. Natural Light
Artificial Light