National Aeronautics and Space Administration
Marshall Space Flight Center
Hinode (Solar-B)
Solar History Timeline
The Origin of the Cosmos, Earth, Sun, and Humans
Image Credits: Proto solar nebula: Spitzer Space Telescope
13.7 billion years - Formation of hydrogen and helium in Big Bang
4.9 billion years - Oldest meteorite forms
4.58 billion years - Most consistent age for formation of sun
4.54 billion years - Age of Earth
4.4 billion years - Sun begins life only 70% current brightness
3.5 billion years - Earth day is 15 hours long
3.0 billion years - Oldest record of Earth's magnetic field
3.0 billion years - Sun grows in brightness to 80% of current level.
2.0 billion years - Solar luminosity is now 85% of current level.
900 million years - Length of day is now 18 hours long.
750 million years - Large ice packs cover earth nearly to equator
543 million years - Cambrian Explosion of complex organisms.
500 million years - Solar luminosity only 6% less than today.
320 million years - First ancestors to mammals appear
300 million years - Solar luminosity only 3% less than today.
250 million years - Permian Mass extinction
100 million years - Earth's magnetic field 3x stronger than today
65 million years - Cretaceous Dinosaur Extinction
60 million years - Primitive primates appear
55 million years - Major global warming episode
27 million years - Primitive apes emerge
6 million years - Great Apes and Hominids 'split' genetically
2 million years - Tool-making humanoid ancestors emerge
750 thousand years - End of last magnetic reversal
500 thousand years - First evidence of fire usage
400 thousand years - First use of paint by human ancestors
150 thousand years - Neanderthal's appear
130 thousand years - Beginning of Eemian Interglacial age
100 thousand years - Modern humans appear
50 thousand years - Major change in human behavior, art, tools
45 thousand years - Largest animals disappear from human habitats
28 thousand years - Neanderthal's disappear
25 thousand years - Elaborate burial customs appear
20 thousand years - Start of last Ice Age
17 thousand years - Oldest star map created on cave wall
12 thousand years - Ice Age ends. Earth grows warmer
10 thousand years - Humans colonize North America
The Origin of the Cosmos, Earth, Sun, and Humans
- NASA Contact: Sabrina Savage
- Page Last Updated: Monday, 01 October 2012