‘What you see is that the most outstanding feature of life’s history is a constant domination by bacteria,’ said Stephen Jay Gould in 2009, a famous American geologist. Bacteria occur widely across the Earth’s surface in an incredible range of hostile environments. At the same time, we imagine the atmosphere as a fairly lifeless environment, save for some birds and high-flying humans. However, scientists were surprised to find unprecedented densities of bacteria at some high elevations, which may lead to some unexpected effects.

Bacteria are some of the hardest species on the planet, so it might not be totally surprising to find them airborne. What is an astounding discovery is NASA’s finding that bacterial densities in the Earth’s upper atmosphere, at elevations of around 10 kilometers, actually exceed bacterial concentrations at lower elevations.

Bacteria densities over the Gulf of Mexico accounted for an incredible 20 percent of all matter sampled by scientists involved in a pioneering study of atmospheric composition. The bacteria are believed to be doing a lot more than floating around aimlessly.

Scientists suspect that the atmospheric bacteria might be responsible for partially controlling Earth’s climatic conditions as well. Theories proposed by some experts and scientists include the idea that bacteria serve as a nucleus around which water and ice crystals may condense, influencing cloud formation and rain patterns.