Earth began forming over 4.6 billion years ago from a cloud of gas and dust that also formed the Sun and other planets. As the solar system developed, small objects called planetesimals collided and stuck together, eventually forming Earth. When Earth first formed, it was a hot molten planet bombarded by asteroids and comets. As it cooled over millions of years, the first life forms of bacteria emerged and the oceans and atmosphere developed. Today, Earth is a complex system made up of interacting spheres including the atmosphere, biosphere, geosphere, hydrosphere, and cryosphere that sustain life.

1. Earth
and
The Solar System

2. EARTH
 Third Planet in Solar system
 Only Astronomical Object
Known to Accommodate Life
 Looks like a small blue
and white marble
(the air, the water, the ice, and the rocks)

3. Earth’s Beginning:
The Origin of life
 Earth is the only planet we know of that
can support life
 Home to billions of plants and animals and
also Human
There are many theories, but most have the
same general perspective of how things
came to be the way they are:

4. Earth’s Beginnings:
Earth began to form over 4.6
billion years ago from the
same cloud of gas
(mostly hydrogen and
helium) and interstellar dust
that formed our sun, the rest
of the solar system and even
our galaxy.

5. Earth’s Beginnings:
The solar system was created
from gas clouds and dust that
remained from the Sun's
formation some 6-7 billion
years ago. This material
contained only about .2% of
the solar system's mass with the
Sun holding the rest

6. Earth’s Beginnings:
As our solar system began to come together, the sun
formed within a cloud of dust and gas that continued to
shrink in upon itself by its own gravitational forces This
caused it to undergo the fusion process and give off light,
heat and other radiation. During this process, the
remaining clouds of gas and dust that surrounded the sun
began to form into smaller lumps which eventually
formed into the planets we know today.

7. Earth’s Beginnings:
A large number of small
objects, called
planetesimals, began to
form around the Sun early
in the formation of the solar
system. These objects were
the building blocks for the
planets that exist today.

8. Hadean Period:
The Earth formed under so much heat and
pressure that it formed as a molten planet
Earth was bombarded continuously by
the remnants of the dust and debris
(like asteroids, meteors and comets
until it formed into a solid sphere, pulled
into orbit around the sun and began to cooldown)

9. Proterozoic Period:
 Free oxygen began to
build up
 This increased oxygen
created conditions that
would not allow most of
the existing life to survive
and thus made way for
the more oxygen-
dependent life forms.

10. Middle period:
 Earth’s surface began to cool and
stabilize, creating the solid surface
with its rocky terrain.
 Clouds formed as the Earth
began to cool, producing enormous
volumes of rainwater that formed
the oceans

11. Archean Period:
 First life began to appear
and the world’s landmasses
began to form
 Earth’s initial life forms
were bacteria, which could
survive in the highly toxic
atmosphere that existed
during this time.

12. Earth
As A
System

13. 5 Parts Of System
 The Atmosphere
 The Biosphere
 The Geosphere
 The Hydrosphere
 The Crysphere

14. The Atmosphere
 The Envelope of Gases
Surrounding the Earth
 Extends up from the
Earth surface for several
Hundred Kilometers
 The lowest part is home to clouds and weather.

15. The Biosphere
 Layer of the Planet Earth
where Life exists.
 Also Non Living Organism
 from Greek
bios = life, sphaira, sphere

16. The Hydrosphere
 The Waters on The Earth's
Surface
 Includes the ocean, rivers,
lakes, streams, groundwater,
water vapor, and even puddles.
 Greek word hydōr, "water" and
sphaira, "sphere”

17. The Geosphere
 Uppermost layers of the solid
Earth
 Includes all minerals, rocks,
molten rock, sediments, and soils
(although there are important
living components to soils as well)
 Geo means “Earth” and
sphaira, "sphere”

18. The Cryosphere
 Frozen water part of the
Earth system
 Includes snow, glaciers,
and sea ice
 Greek cryos "cold",
"frost" or "ice" and sphaira,
"globe”