Scale of the Universe. Illustration depicting the scale of the Universe. From lower left are the smallest objects: the fundamental particles, atoms, molecules such as DNA, and cells. Toward upper right the scale expands further: from the Earth itself to the Solar System, the Milky Way galaxy and on to galaxy clusters and the whole Universe. In the middle is our familiar scale - the human being. The range of scale from the smallest distance (Planck length, largest (diameter of the Universe, about 61 orders of magnitude, written as a ten followed by 60 noughts.