There's also a long-term experiment being performed on the International Space Station: http://knts.tsniimash.ru/ru/site/Experiment_q.aspx?idE=191 http://knts.

There's also a long-term experiment being performed on the International Space Station: http://knts.tsniimash.ru/ru/site/Experiment_q.aspx?idE=191 http://knts.tsniimash.ru/ru/site/Experiment_q.aspx?idE=191 (in Russian, but Google Translate seems to work well on this one) It's not finished yet but apparently preliminary results [1] show that microorganisms can be lifted into the upper atmosphere from the oceans somehow. [1] https://www.energia.ru/ktt/archive/2015/01-2015/01-03.pdf https://www.energia.ru/ktt/archive/2015/01-2015/01-03.pdf