Dr John Ellis contemplates the size of the cosmos in relation to Wales and packs of butter
Tony Robinson asks to what depth 40 trillion trillion trillion packs of butter would cover a country the size of Wales (Letters, 29 June). In scientific notation this is 40×1036 packs. Wales is about 2×1010 square metres. A pack of butter measured 95x63x41mm, so 2×1010÷6×10–3 or 3.4×1012 packs would cover the surface. The height of 40×1036 packs stacked on top of each other comes to 40×1036÷3.4×1012 x 0.041 metres, or 4.8×1023 metres. The sun is only 1.5×1011 metres away, but Saturn is a little farther at 1.4×1012 metres from the sun, while Pluto is at 5.9×1012 metres. Andromeda is a mere 2.4×1022 metres away. You could therefore, if you arranged the packs as steps, climb this “butter mountain” and reach all of the planets in the solar system, then go on to Andromeda, but you’d have to do it at night or the stairway to the solar system would swing past the sun and melt.
Dr John Ellis