1. Life On Earth Why does Life Exist on Earth?

2. Essential Standard 6.E.1 Understand the earth/moon/sun system, and the properties, structures and predictable motions of celestial bodies in the Universe.

3. Clarifying Objective 6.E.1.2 Explain why Earth sustains life while other planets do not based on their properties (including types of surface, atmosphere and gravitational force) and location to the Sun.

4. Essential Questions What are the conditions needed for life on Earth? What conditions on other planets make it unsuitable for life?

5. Earth The Earth is the 3 rd planet from the sun It contains both landmasses & oceans It is the ONLY PLANET that is known that CAN SUPPORT LIFE This is why

6. Location from the Sun Earth is the only planet that is the CORRECT LOCATION from the SUN to have life Earth’s location from the sun is the reason that conditions for life are possible If the planet were closer to the sun life would be impossible as it would be if it were further from the sun

7. 6 Conditions for Life For any planet or moon or anything to support life (anything from bacteria to humans) you have to have 5 conditions ①Water ②Atmosphere (Oxygen) ③Correct Temperature ④Light ⑤Correct Gravity ⑥Types of Surfaces

8. Water The first ingredient you need to sustain life is WATER Water must exist in liquid form or have the ability to become liquid Water is the breeding ground for chemical reactions essential to life On earth you can find water in all three medium forms (solids, liquids, gasses) http://www.youtube.com/wat ch?v=3eSTQ1KYKIE http://www.youtube.com/wat ch?v=3eSTQ1KYKIE http://www.youtube.com/wat ch?v=FOmoO6Xj1sw http://www.youtube.com/wat ch?v=FOmoO6Xj1sw

9. Atmosphere The second key ingredient is the RIGHT kind of Atmosphere An ATMOSPHERE that can sustain life MUST contain high amounts of OXYGEN Oxygen is the key in the atmosphere for life to exist http://www.youtube.com /watch?v=muwCjTJHrUI http://www.youtube.com /watch?v=muwCjTJHrUI

10. Correct Temperature The third ingredient is having the CORRECT TEMPERATURE for life to exist The earth is one of two planets (Mars) to have the correct temperature for life to exist The temperature has to be between 30-180 degrees Other planets are either too close (hot) or too far (cold) to sustain life

11. Light The fourth ingredient is LIGHT To sustain life a planet must have light Light gives all living things energy and it starts the food cycle Light is the key to starting photosynthesis which is how plants make their food http://www.youtube.com/w atch?v=4fYLEhqYGIU http://www.youtube.com/w atch?v=4fYLEhqYGIU

12. Food Chain

13. Correct Gravity The 5th ingredient is the CORRECT amount of GRAVITY on the planet Remember gravity is the force that holds you to the ground and controls weight All planets have a gravitational pull to the sun http://www.youtube.com /watch?v=tIn_EvuNEh4 http://www.youtube.com /watch?v=tIn_EvuNEh4

14. Correct Gravity The closer the planet to the sun the more gravity they have The further from the sun the less gravity they have If the planet is too far from the sun the atom particles you are made up would disintegrate If you were too close your legs would break because your bones would not be strong enough to handle the increased weight http://focus.org.uk/gravity.php

15. Types of Surfaces The last ingredient is the CORRECT TYPE of SURFACE for life The surface of the Earth is composed of both land & water It is the only planet surface publically known to be conducive to life

16. Why can Earth Sustain Life? Earth can sustain life and no other planet can because all of these FACTORS exist at the SAME TIME ①Correct Distance from the sun ②Water in liquid form ③Atmosphere with Oxygen ④Correct Temperature ⑤Light ⑥Correct Gravity ⑦Right Surface

17. Essential Questions Get with a partner and answer… What are the conditions needed for life on Earth? What conditions on other planets make it unsuitable for life?

18. EOG Questions Which factor makes Earth different from all the other planets in the solar system in its ability to support life? A) The Earth is exposed to rays from the sun. B) The Earth has only one moon that orbits around it. C) The Earth rotates in an elliptical orbit around the sun. D) The Earth has a breathable atmosphere.

19. Important Points Earth is the only publically known planet to support LIFE There are 6 key ingredients to support life ①Water in liquid form ②Correct Temp ③Correct Gravity ④Atmosphere w/Oxygen ⑤Light ⑥Correct Surface Type At least one of these FACTORS does NOT exist on all the rest of the planets in the Solar System