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Most previous work growing bacteria in space has focused on species known to contain pathogenic strains (e.g. _Escherichia coli_ \cite{9043122} \cite{12521048} and Pseudomonas \cite{21169425} \cite{24192060}), and much less attention has been paid to the "normal" microbes that surround us (i.e., species not known to be pathogenic). An understandable bias towards pathogens and pathogenic pathways is highlighted by work on topics such as biofilm formation (\cite{23658630}, \cite{11179638}), antibiotic resistance/production (\cite{16091928}, \cite{11543359}, \cite{12483468} reviewed in \cite{16460819}), and virulence (\cite{10816456}, \cite{24283929}).  While concern about pathogens in spacecraft is certainly warranted, it should be emphasized that the ability of a pathogen to survive outside a host and the ability to infect a host are both, at least in part, dependent on the existing community of non-pathogenic  microbes in those locations. For example, mechanically ventilated hospital air shows a much higher abundance of potential pathogens \cite{22278670}, presumably due to the lack of inflow or competition from other microbes. Similarly, the infectivity of some pathogens has been shown to be very dependent on the host microbiome (e.g. \cite{26511795}, \cite{21402903}, \cite{26374122} \cite{21804357}). Therefore, it is important to understand the entire microbial ecosystem of spacecraft. Indeed, in recent years, several culture-independent studies have examined the microbiome of the ISS (\cite{14749908}, \cite{24695826}, \cite{Moissl_2007}), including another part of Project MERCCURI (Lang _et al._ submitted). These studies have shown, not surprisingly, that the microbiome of the ISS bears a strong resemblance to the microbiome of human-associated built environments on earth. Therefore it is of interest to see how microbes from human-associated environments behave in space. For this study, samples from human-associated surfaces (e.g. toilets, doorknobs, railings, floors, etc.) were collected at a variety of locations around the United States, usually in collaboration with the public. A wide variety of bacteria were cultured from these samples, and 48 non-pathogenic strains were selected for a growth assay comparing growth in microgravity on the ISS and on earth.