Small particles from Comet 67PChuryumov-Gerasimenko, obtained by multiple instruments on the Rosetta mission, are furthering our understanding of some big science. br br The formation and evolution of our Solar System played a vital role in how Earth, and the human race, came into existence. Since comets are remnants from our early Solar System, even a grain of microscopic dust can offer insight. Recently the orbiter’s COSIMA instrument discovered organic material in the form of carbon, far more complex than expected, inside several particles collected from the comet’s coma, or atmosphere. Its best match is a meteorite in the Orgueil collection, in France, which came from a now extinct comet. br br The COSIMA, GIADA and MIDAS instruments have all been collecting particles but MIDAS is concentrating on those smaller than 50 micrometres. One of these particles is special as it has an unusual repeating, fractal-like structure, seen for the first time in a comet and thought to be a survivor of the violent compaction process during the comet’s formation. br br Rosetta’s results are therefore having an impact on how scientists view the evolution of our Solar System, including our home planet.