The History of Planet Earth
In The Beginning....
The Eras of Earth
Hadean Eon (4567 to 3800 mya)
-4650 mya: Formation of chondrules in the Solar Nebula
-4567 mya: Formation of the Solar System, Sun was only 70% as bright as today.
-Earth's original hydrogen and helium atmosphere escapes Earth's gravity
-3900 mya: Cataclysmic meteorite bombardment.The Moon is 282,000 km from Earth. Earth day is 14.4 hours long- Earth's atmosphere becomes mostly
carbon dioxide, water vapor,
methane, and ammonia.
- Formation of carbonate minerals starts
There is no geologic record for the Hadean Eon.
Archean Eon (3800 to 2500 mya)
Water started condensing in liquid form.
- Earth day is 15 hours long
- 3500 mya: Monocellular life started (Prokaryotes). First known oxygen-producing bacteria
-3000 mya: Atmosphere has 75% nitrogen,15% carbon dioxide.
- Sun brightens to 80% of current level.
- Oldest record of Earth's magnetic field.
Proterozoic Eon (2500 to 542 mya)
Siderian Period (2500 to 2300 mya)
Rhyacian Period (2300 to 2050 mya)
Orosirian Period (2050 to 1800 mya)
Statherian Period (1800 to 1600 mya)
Mesoproterozoic Era (1600 to 1000 mya)
Calymmian Period (1600 to 1400 mya)
Ectasian Period (1400 to 1200 mya)
Stenian Period (1200 to 1000 mya)
Neoproterozoic Era (1000 to 542 mya)
Tonian Period (1000 to 850 mya)
Cryogenian Period (850 to 630 mya)
Ediacaran (Vendian) Period (630 to 542 mya)
Phanerozoic Eon (542 mya to present)
Paleozoic Era (542 to 251 mya)
Tommotian Stage (534 to 530 mya)
Ordovician Period (488.3 to 443.7 mya)
Silurian Period (443.7 to 416 mya)
Devonian Period (416 to 359.2 mya)
Carboniferous Period (359.2 to 299 mya)
Mississippian Epoch (359.2 to 318.1 mya)
Pennsylvanian Epoch (318.1 to 299 mya)
Permian Period (299 to 251 mya)
- 275 mya: Formation of the supercontinent Pangea
Conifers and cycads first appear
- Earth is cold and dry
- Sail-backed synapsids like
Edaphosaurus and Dimetrodon appeared
- 260 mya: End of Karoo ice age.
- 251 mya: * Mass extinction (Permian-Triassic)
- Possible 480km-wide meteor crater in the
Wilkes Land region of Antarctica 
- Period of great volcanism in Siberia releases
large volume of gases (CO2, CH4, and H2S) 
- Oxygen (O2) levels dropped from 30% to 12%
Carbon dioxide (CO2) level was about 2000 ppm
Temperatures reach 50-60°C on land, and 40°C at the sea-surface.
Earth's worst mass extinction eliminated
90% of ocean dwellers, and 70% of land
plants and animals.
Cenozoic Era (65.5 mya to today)
Paleogene Period (65.5 to 23.03 mya)
Tertiary Period (65.5 to 2.58 mya)
Paleocene Epoch (65.5 to 55.8 mya)
- 63 mya: End of Deccan Traps volcanic eruptions in India
- Flowering plants become widespread.
- Social insects achieve ecological dominance.
Eocene Epoch (55.8 to 33.9 mya)
Earth day is 24 hours long.
The Moon is 378,000 km from Earth.
Oligocene Epoch (33.9 to 23.03 mya)
- Appearance of many grasses
- First elephants with trunks
Neogene Period (23.03 mya to today)
Miocene Epoch (23.03 to 5.3 mya)
- African-Arabian plate joined to Asia
Warmer global climates
- First raccoons appear.
Pliocene Epoch (5.3 to 2.58 mya)
Animals and plants cross the new land bridge.
Ocean currents change in the newly isolated Atlantic Ocean.
Quaternary Period (2.58 mya to today)
Pleistocene Epoch (2.58 mya to 11,400 yrs ago)
- Several major episodes of global cooling, or glaciations
Several major episodes of global cooling, or glaciations
- 2.4 mya: Homo habilis appeared
- 2.1 mya: Yellowstone supervolcanic eruption
- 2 mya: Tool-making humanoids emerge.
Beginning of the Stone Age.
Holocene Epoch (11,400 years ago to today)
- Development of agriculture
- Domestication of animals.
Development of agriculture
- Domestication of animals.
- 9,000 yrs ago: Metal smelting started
- 5,500 yrs ago: Invention of the wheel
- 5,300 yrs ago: The Bronze Age
- 4,500 yrs ago: Pyramids of Giza
- 3,300 yrs ago: The Iron Age
- 2,230 yrs ago: Archimedes advances mathematics
- 250 yrs ago: Start of the Industrial Revolution
- 50 yrs ago: Space travel
Artificial satellite orbits the earth (1957).
Humans walk on the surface of the moon (1969).
The Habitable Earth we Know Today