Earth, our home planet, is the only planet whose name is not derived from Greek/Roman mythology. In Roman Mythology,
the goddess of the Earth was Tellus - the fertile soil, while the Greek goddess was Gaia, terra mater - Mother Earth. The
name we use today, Earth, comes from Old English and Germanic.
1. Earth is the third planet from the Sun-The Earth's average distance from the Sun is 149,597,890 km
(92,955,820 miles) or one astronomical unit (AU). Located between Venus and Mars, some people have
called it the "third rock from the sun."
2. Earth is the fifth largest planet-The diameter of the earth at the equator is about 7926 miles, but that's
not the whole story. Because the earth is not a perfect sphere but is slightly flattened at the poles, the
diameter of the earth measured around the North Pole and the South Pole is about 7899 miles.
3. Earth is the only planet known to harbor life- All of the things we need to survive are provided under a
thin layer of atmosphere that separates us from the uninhabitable void of space. Earth is made up of air,
water, land, and life - including humans - combine forces to create a constantly changing world that we are
striving to understand. The conditions on earth is very suitable for life, which is termed as Goldilock’s
condition.
4. Earth is mostly covered in water-While the word earth is often used synonymously with dirt, seventy-one
percent of the its surface is covered with water. It is the only planet where it exists in its liquid form on the
surface. This is probably part of the reason that the Earth is the only planet known to contain life.
5. Early philosophy had the Earth as the center of the universe- Although Aristarchus of Samos, in the
3rd Century B.C., figured out how to measure the distances to and sizes of the Sun and the Moon, and
concluded that the Earth orbited the Sun, this view didn't attract followers until Nicolaus Copernicus, a
Polish astronomer, said that earth revolve around the Sun" in 1543.
6. Earth has four distinct seasons-This is a result of a result of Earth's axis of rotation being tilted
more than 23.5 degrees. Seasons changes as the tilt of Earth's axis changes during its revolution
around the Sun, not the distance between the earth and the Sun.. Earth rotating on its axis
causes day and night.
7. Earth has an atmosphere that sustains life-Earth's atmosphere is 78% nitrogen, 21% oxygen,
with traces of argon, carbon dioxide and water. This atmosphere affects Earth's long-term climate
and short-term local weather; shields us from nearly all harmful radiation coming from the Sun;
and protects us from meteors as well - most of which burn up before they can strike the surface.
8. Earth has one natural satellite-Earth's Moon (called Luna) orbits at a distance of 384,000km, with a radius
of 1738 Km and a mass of 7.32x 10 22 kg. However, there are thousands of small artificial satellites which have
been placed in orbit around the Earth.
Because of its size and rocky composition, the moon has also been called a terrestrial planet along with Mercury, Venus,
Earth, and Mars. It has no atmosphere, but there is water ice in some deep craters. The moon is the only extra-planetary
body that a human has visited.
9. Earth has a magnetic field-Our planet's rapid spin and molten nickel-iron core give rise to a magnetic field.
When charged particles from the solar wind become trapped in Earth's magnetic field, they collide with air
molecules above our planet's magnetic poles. These air molecules then begin to glow and are known as the
aurora, or the Northern and Southern Lights. The magnetic field also protects us from cosmic radiation or radiation from
space that is harmful to us.
10. Our close proximity prevents us from seeing Earth in its entirety-To completely view our own planet,
we must leave its surface and journey into space. From the vantage point of space we are able to observe
our planet globally, as we do other planets, using similar sensitive instruments to understand the delicate
balance among its oceans, air, land, and life. Viewing Earth from the unique perspective of space provides the opportunity
to see Earth as a whole. Scientists around the world have discovered many things about our planet by working together
and sharing their findings.
http://space.about.com/od/earth/tp/Earth_10_Things.htm
10 things About our Planet
Environmental Science
Name: ________________________________________________ Period: ______ Date: ___________________
Essential Question: How do I describe Earth?
Instructions: Read the paragraphs at the back and answer the following questions.
1. What does Gaia mean?
____________________________________________________________________________________________________
2. Earth’s diameter is _____________equator ,____________poles . The Earth is not a perfect
_________________________ but is slightly _____________________ at the ____________________________.
3. What is the only planet that harbors life? ______________________________________________________
4. How can Earth support life? _________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
5. How many percent of Earth is covered with water? ______________________________________________
6. Who is the polish astronomer who published that the Earth orbited the Sun? _________________________
7. How many seasons does earth have? ___________________. Earth has seasons because ________________
___________________________________________________________________________________________
____8. How does the tilt of the Earth’s axis affect the seasons? Think!
A. by changing the amount of direct solar energy reaching the surface of Earth
B. by influencing the rate of chemical reactions occurring in the atmosphere
C. by deflecting the harmful rays of radiation emitted by the sun
D. by changing the speed of the rotation of Earth
_____9. Which 1occurs as a result of Earth rotating on its axis? Think!
A. volcanic eruption
C. deep ocean currents
B. seasonal changes
D. day and night
10. The composition of Earth’s atmosphere is_____________________________________________________
___________________________________________________________________________________________
11. How are we protected by Earth’s atmosphere?_________________________________________________
___________________________________________________________________________________________
12. What is Earth’s natural satellite? ____________________________________________________________
13. Why is the moon full of craters? Think! _______________________________________________________
14. The Earth’s magnetic field is caused by _______________________________________________________
___________________________________________________________________________________________
15. What causes the aurora, or the Northern and Southern Lights? ___________________________________________
____________________________________________________________________________________________________
16. Why is the Earth’s magnetic field important to us? ______________________________________________
___________________________________________________________________________________________
17. Why can’t we completely view our planet?
___________________________________________________________________________________________
18. How do scientists learn about our planet? Think!
___________________________________________________________________________________________
___________________________________________________________________________________________
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R.Angat