Choose your fighter for the origin of water on Earth! Was it always here or did it come to this planet from somewhere else in space? And, either way, what does this mean for other water worlds in our galaxy? To find out, we talk with Michael Wong, an astrobiologist and planetary scientist at Carnegie Science. He gets into scientists’ strongest candidates for the ways water could have come to our planet many, many years ago – including whether it could have been made here. Buckle up: This is a hot debate in astrobiology right now.

If you enjoyed this episode, check out our Space Camp series and our episode on whether life started on the ocean floor..

Interested in more space science and more unresolved hypotheses about how the universe came to be how it is today? Email us your question at [email protected].

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