Ingredients for Life

1. The raw materials for life all ultimately came from space.

MS-ESS2-d, HS-ESS1-f

2. Elements such as the calcium in our bones and the iron in our blood were formed in previous generations of stars.

MS-ESS1-g, HS-ESS1-b, HS-ESS1-c, HS-ESS1-g

• The early Universe was composed mostly of hydrogen with a little helium and lithium, as well as trace amounts of heavier elements.
• Supernova explosions and “soot” from massive stars enriched the hydrogen and helium in the early Universe with heavier elements.
• Radioactive isotopes can be used to determine ages of samples to help date important events in the history of the Earth and life.

3. Water is essential for life and was present in the raw materials that formed the Earth, as well as in comets that rained down upon the Earth.

2-ESS2-a, 2-ESS2-f

4. Organic materials have been found in space.

MS-ESS1-d, HS-ESS1-j

• Complex organic molecules have been found in meteorite and comet samples, and have been detected through our observations of stars and gas in space.
• The currently available evidence for life on other planets in our Solar System is not convincing.