when you have comets?
http://www.rawstory.com/2016/05/building...67ps-halo/
http://www.rawstory.com/2016/05/building...67ps-halo/
Quote:Now, a new study, based on data gathered by instruments on board the European Space Agency’s (ESA) Rosetta spacecraft — which is currently following the comet 67P/Churyumov-Gerasimenko — further bolsters the possibility that the building blocks of life on Earth may have come from outer space.
Researchers have detected the amino acid glycine, commonly found in proteins, and phosphorus, a key component of DNA and cell membranes, in the coma of the comet.