RECENT developments in the synthesis of macroscopic amounts of the C60 and C70 carbon clusters1-3 have made possible spectroscopic1,2,4-7 studies of these species. Infrared1,2 and vibrational Raman4 spectra strongly support the proposed 'soccer ball' structure for the C60 cluster8, and NMR spectroscopy directly confirms its icosahedral symmetry5,6. Here we present images of C60 clusters obtained with the scanning tunnelling microscope. These species are roughly spherical and form mobile hexagonal arrays on a Au(lll) surface with an intercluster spacing of 11.0 Å Brighter features evident in the arrays are tentatively identified as C70 clusters. © 1990 Nature Publishing Group.