In this work we present an scientific application that has been given a Hadoop MapReduce implementation. We also discuss other scientific fields of supercomputing that could benefit from a MapReduce implementation. We recognize in this work that Hadoop has potential benefit for more applications than simply data mining, but that it is not a panacea for all data intensive applications. We provide an example of how the halo finding application, when applied to large astrophysics datasets, benefits from the model of the Hadoop architecture. The halo finding application uses a friends of friends algorithm to quickly cluster together large sets of particles to output files which a visualization software can interpret. The current implementation ...