Mercury 'painted black' by passing comets - BBC News

BBC News
Mercury 'painted black' by passing comets
BBC News
Mercury's dark surface was produced by a steady dusting of carbon from passing comets, a new study says. Mercury reflects very little light but its surface is low in iron, which rules out the presence of iron nanoparticles, the most likely "darkening agent".
Scientists find the 'invisible paint' that makes Mercury darker than darkWashington Post
Mercury is “painted black” by cometary dust over billions