What’s the difference between a fact, a law, and a theory? Mineralogist Robert Hazen and astrobiologist Michael Wong unpack the hierarchy of scientific ideas and reveal how laws of nature elegantly unify the universe.

For more, check out the extended interview with Robert Hazen and Michael Wong.

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Sorry, Beyoncé, it turns out microbes rule the world. Microbiologist Peter Girguis explains how to conceptualize just how many microbes are on Earth… and how understanding this helps us look for life on other worlds.

For more, check out the extended interview with Peter Girguis.

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Scientists have discovered the oldest DNA ever found: tiny fragments hidden in the dirt. The idea that soil could hold genetic traces from creatures that vanished millions of years ago seemed impossible – until one researcher had the wild idea to go and look. But how did he find DNA that most scientists thought could never survive? What forgotten worlds can this buried DNA reconstruct? And what might these revelations tell us about our own future on a rapidly changing planet?

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