1.Introduction To understand why Earth has been so conducive to life, we need to identify key conditions that make it habitable and ask why they exist.

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1. Introduction

To understand why Earth has been so conducive to life, we

need to identify key conditions that make it habitable and ask why they exist here but not on

neighboring planets.

http://www.99hdwallpaper.com/nature/beach.html

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DID YOU KNOW?

The Universe includes allthe planets, stars and cosmic debris. The current view is thatthe Universe is between 12-15 billion years old.

The center of our solar system is our Sun, a medium-sized star.We know the universeincludes hundreds of billions of stars and billions of other solar systems.

Do you think ours is theonly solar system thatsustains life?

7. Our solar system formed form a solar nebula, or cloud of gas and dust, that collapsed and condensed about 4.56 billion years ago. 8. Most of the gas and dust compacted together to form the sun, while the remainder formed planets, asteroids, and smaller bodies.

http://solar.teasss.com/solar-system-theory/

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9. Compare and contrast the Sun, Mercury, Venus, Earth, Mars, J upiter, Saturn, Uranus and

Neptune by placing an X in the boxes that apply under each. Sun Mercury Venus Earth Mars J upiter Saturn Uranus Neptune

Outer planets

Terrestrial planets

4 condensed at cold temperatures 4 higher temps 4 closer to sun 4 farthest f rom sun

Contain large amounts of iron, silicates, magnesium Made mostly of helium and hydrogen

X

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The young Earth was anything but habitable. Radioactive elements decaying within its mass and impacts from debris raining down from space generated intense heat.

http://amp.wpcamr.org/archives/135

10. List 3 reasons why the young Earth was not habitable.

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11. What was the period of time from about 4.5 to 3.8 billion years age called and why?

The first eon of Earth’s history, from about 4.5 to 3.8 billion years ago, is named the hadean after hades, the Greek word for hell because of the intense heat on Earth. Most original rock from this period was melted and recycled into Earth’s crust, so very few samples remain from our planet’s formative phase.

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12.What are meteorites and what can scientist learn from studying them?

Meteorites are stony or metallic fragments up to 4.5 billion years old that fall to Earth from space.

Scientists can see what materials were present when the solar system was formed and how similar materials may have been melted, crystallized, and transformed as Earth took shape.

http://www.footballphds.com/wp-content/uploads/2013/02/When-Ancient-Aliens-attack.png

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The Willamette Meteorite, the largest ever found in the United States (15 tons)The Willamette Meteorite is probably a fragment from the core of an ancient planet that broke up as it orbited the sun. Its structure suggests that it sustained at least two high-energy impacts in space before it fell to Earth's surface and weathered further.

www.learner.org

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Meteor Crater in Arizona is the breath-taking result of a collision between a piece of an asteroid traveling at 26,000 miles per hour and planet Earth approximately 50,000 years ago.

http://www.virtualtourist.com/travel/North_America/United_States_of_America/Arizona/Meteor_City-749944/TravelGuide-Meteor_City.html

Video about the craterhttp://www.youtube.com/watch?v=aoGvlYCkD6Q

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Meteor Crater is nearly one mile across, 2.4 miles in circumference and more than 550 feet deep.

http://onestep4ward.com/top-5-arizona/

Large buildings and parking lots

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Big Story: Russia Meteor Blast is Biggest in 100 Years

The dramatic fireball that exploded over Russia today (Feb. 15) was apparently the biggest such blast in more than a century, scientists say. The object that caused the Russian fireball, which damaged hundreds of buildings and wounded perhaps 1,000 people in the Chelyabinsk region, was originally probably about 50 feet (15 meters) in diameter and weighed roughly 7,000 tons, said Peter Brown, director of the Center for Planetary Science and Exploration at the University of Western Ontario in Canada –

View video here: http://www.space.com/19807-raw-video-meteorite-crash-in-russia-sparks-panic.html

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13. About 4 billion years ago, Earth’s surface began cooling which allowed for water vapor to condense in the atmosphere and fall back as rain.

http://science.howstuffworks.com/environmental/earth/geophysics/h2o6.htm

12http://www.houghtonmifflinbooks.com/booksellers/press_release/studentscience/gif/watercycle1.gif

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14.Rock weathering is a key part of the carbon-silicate cycle that regulates Earth’s climate.

http://ore.conroeisd.net/Teachers/kwardrup/157DA2E7-00870B2F.1/arizona-rock-Weathering.jpg

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15.How long do scientist believe oceans have been around?

3.5 billion years ago

http://www.earthgauge.net/wp-content/uploads/2012/05/ocean2.jpg

15Venus Earth

16.View page 4 and list 5 facts about Venus

- Nearly the same size and density as Earth

- About 30% closer to the sun than Earth- Called Earth’s “sister planet”- Stifling inferno – surface temperature

460°C or 860°F- Dense atmosphere, 100 times thicker than

the Earth’s- Atmosphere made up of almost entirely CO2

- Clouds on Venus consists mainly of sulfuric acid droplets

- .

http://singularityweblog.zippykid.netdna-cdn.com/wp-content/uploads/2012/06/Venus-Earth-Comparison.jpg

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17. What does it mean by Venus having a higher albedo than Earth?

Albedo means Venus’s surface is brighter than Earth’s surface. Because of this, Venus is an inferno because it’s thick atmosphere traps the reflected light like a heavy, thick blanket.

18. View page 5 and list 5 fact about Mars.

- Much colder than Earth- Clouds of ice and frozen CO2 drift over its

surface. - Frozen ice caps at the poles reflect sunlight- Atmosphere consists mainly of CO2 - Mars atmosphere is 100 times thinner than

Earth’s atmosphere, so it provides only a small warming effect

- Called the “RED PLANET”- All water on Mars is frozen

Mars Land Rover NASA's Curiosity rover celebrates one year on Mars August 2013

http://www.spacetoday.org/images/Mars/MarsRovers2003/MarsRover2003_2.jpg

http://www.space.com/22226-mars-rover-curiosity-time-lapse-video.html