Phosphorus is one of the five elements essential for life. It’s represented on the periodic table by the letter P.

Phosphorus is key to building bones and teeth and as the building block for the fuel that powers our growth and movement. You might remember adenosine triphosphate, or ATP, from high school biology class.

Each day the human body makes, uses and recycles its entire weight in ATP to drive our cellular function.

Phosphorus is not very common on the surface of Earth, where it’s mostly found in phosphates, which are compounds of phosphorus and oxygen.

These are not very reactive—or biologically useful. So, living things have to get their phosphorus from something else.

Scientists are now studying more reactive, useful compounds of phosphorus called phosphides. Many of these occur in meteorites. And as we’ve talked about on other episodes, in Earth’s distant past, the planet was pummeled by them.

Scientists now think that much of the biologically available phosphorus on Earth came from these ancient meteorites.

Phosphates can also be converted into bioavailable phosphides when they’re struck by lightning.

Early Earth may have had 10 times the lightning as today, which could also have unlocked phosphates in rock and soil for use by lifeforms.

P may be for phosphorus. But thanks to meteorites and lighting, P is also for life.