Scientists discover the Goldilocks secret behind life on Earth

Earth may have won a cosmic chemistry lottery. Researchers found that during the planets earliest formation, oxygen had to be in an extremely narrow Goldilocks zone for two life-essential elements, phosphorus and nitrogen, to stay where life could use them. Too much or too little oxygen, and those ingredients could be lost or trapped deep inside the planet. This could reshape the search for life by showing that water alone is not enough.