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Because we know that most microbes are recalcitrant to maintenance in culture, we know that these earliest studies were limited by their reliance on culturing to identify microbial species. Culture-independent approaches were eventually implemented, including 16S rDNA PCR surveys \cite{14749908} and the Lab-On-a-Chip Application Development\cite{19845447} Portable Test System (LOCAD-PTS), which allows astronauts to test surfaces for lipopolysaccharide (LPS - a marker for gram negative bacteria). Originally launched in 2006, the capability of the LOCAD-PTS was expanded in 2009 to include an assay for fungi (beta-glucan, a fungal cell wall component) and gram positive bacteria (lipoteichoic acid, a gram positive cell wall component.) This year, the first large-scale, culture-independent 16S rDNA PCR survey was published using the Roche 454 platform, looking at dust on the ISS \cite{24695826}. We report here on a further effort to use 16S rDNA PCR sequencing, on the Illumina platform, to examine the microbial communities found on 15 surfaces inside the International Space Station.  Kawamura et al 2001. Using culturing and a bit of taxa-specific PCR to assay microbes on Mir. Cite in intro. 10.1111/j.1348-0421.2001.tb01321.x/pdf  Moissel 2007. Used 16S surveys (full-length primers followed by TOPO cloning) to examine the earthbound ISS simulator which attempts to replicate the conditions on the ISS as much as possible. Cite in intro? http://dx.doi.org/10.1017/S1473550406003533  We have also compiled a collection of such papers in an online resource to provide a more comprehensive historical perspective of this kind of work (see http://www.mendeley.com/groups/844031/microbiology-of-the-built-environment/papers/added/0/tag/space/).   This microbial census of ISS surfaces is a component of a larger project (Project MERCCURI) which was done not just for the science but also for its outreach and education potential. Project MERCCURI (Microbial Ecology Research Combining Citizen and University Researchers on the ISS) is a collaborative effort of UC Davis (microBEnet), Science Cheerleader, NanoRacks, Space Florida, and Scistarter.com. Project MERCCURI includes three components. Aim 1 involves collecting microbes (by swabbing surfaces) from sporting venues and other high-profile built-environment locations. This component included a concurrent outreach effort in which 2000 "Citizen Scientists" were asked to collect microbes from their cell phones and shoes using sterile swabs. These swabs were sent to the Earth Microbiome Project lab for microbial community analysis. Aim 2 is a bacterial growth assay, in which non-pathogenic microbes collected from the surfaces in Aim 1, "compete" against each other, both on the surface of the Earth (at UC Davis) and onboard the ISS. For Aim 3, the results of which are presented here, astronauts were asked to swab 15 surfaces onboard the ISS to collect microbes for DNA sequence-based identification, a service also provided by the Earth Microbiome Project.