Origin of Earth’s Water

No one knows if our solar system, with a planet possessing the necessary ingredients for life within our Sun’s habitable zone, is a cosmic rarity. Nor do we know whether the gas giants in our solar system played a role in helping to deliver the essential materials for life to the habitable zone. The answers to these questions are contained ices found in small bodies (comets and asteroids) mostly unchanged since the formation the solar system. Their compositions provide a fossilized record of the chemical make-up of our planetary system during its origin. The most likely source of Earth’s water may have come from the outer solar system. Evidence of what arrived at Earth is hard to determine from Earth’s materials because of all the geological the processing that has occurred. This talk will explore what we know about the origin of Earth’s water, and the new ideas for space missions that could help solve this question.W. M. Keck Observatory wishes to offer our deepest gratitude to our Astronomy Talk Series sponsors, Rob and Terry Ryan.