Finding a Better Way to Distinguish Life from Non-Life

The search for life on other worlds needs a way to sift through the chemistry of their atmospheres. If another species observed Earth to search for life, they'd look for "smoking gun" chemistry in the atmosphere. That includes looking for oxygen, since it is created through photosynthesis by plants and some bacteria. So, the key is to look for life-dependent chemical "signals" at exoplanets.