Chesapeake Blast

An asteroid struck Earth 35 million years ago, creating the depression that was eventually filled with water and became Chesapeake Bay. The impact and subsequent firestorm killed off most life in the area. Most, but not all.

Researchers have recently found that some microbes survived the disaster. They were living deep undergound-- deep enough not to feel the full force of the heat generated by the impact. Researchers also believe other microbes recolonzed the area relatively quickly after the event.

Such findings emphasize how difficult it seems to be to eradicate life after it has established itself. Periodic extinctions have threatened life on Earth, but nothing has yet delivered the knockout blow. Indeed, life has been incredibly resilient, bouncing off each extinction and creating arrays of magnificent and complex forms.

Resilience augurs well for finding life on other worlds. If life established itself on a more hospitable early Mars, for example, odds might be good that it endured long enough to leave evidence we can find. It may even still exist.