Scale of the Universe. Illustration depicting the scale of the Universe. From upper left are the smallest objects: the fundamental particles, atoms, molecules such as DNA, and bacteria. The scale expands further: from a human to the Earth itself to the Sun, a nebula, some galaxies and on to the whole Universe. In the middle is our familiar human scale (silhouetted human figure). The range of scale from the smallest distance (Planck length) to the largest (diameter of the Universe), is about 61 orders of magnitude, written as a ten followed by 60 noughts.