Life as we never knew it.

NASA announced yesterday that it had discovered life on earth. Yes, this might not be big news, but the life it discovered is unlike any other. You see, NASA found bacteria that uses arsenic in place of phosphorous.

Still unclear. Ok, let’s simplify this.

All life every discovered has certain things in common. For example, all life uses 6 elements: carbon, oxygen, nitrogen, hydrogen and sulfur and phosphorous. This newly discovered life dispense with phosphorous and substitutes (usually poisonous) arsenic.

Unique bacteria alters our view of life.

Arsenic and New Life

This bacteria wasn’t exactly discovered, so much as altered. NASA pulled the bacteria from the bottom of Mono Lake (in California) and grew it in a lab which required it to adjust to a new environment. The bacteria adjusted, gradually swapping out phosphorous and substituting arsenic into its system.

What’s the significance of all this? The main thing is: NASA needs to expand what it’s looking for when it is looking for life beyond earth. For example, the Viking spacecraft that landed on Mars in 1976 were designed to look for life in the known configuration. Since then, we’ve learned about life that can survive in a variety of extreme environments, using novel strategies. And now we’ve discovered (or created) this strange bacteria.

What Hasn’t Been Discovered

Considered the key building block of life, carbon is central. And “life as we know it” is also called “carbon-based life.” Even this new bacteria is carbon-based.

But in science fiction, and in speculative essays by scientists, the idea of life based on something else (usually silicon) and NOT carbon is said to…well, maybe…be possible. This has yet to be discovered. So, while this strange bacteria is a big, big discovery…the bigger one has yet to be found. Is there life somewhere that has swapped out carbon and substituted silicon? Nobody knows.