“Due to the difficulty in contemplating the sheer magnitude of [the universe], scientists often use clever anecdotes and analogies. Here’s a good one for understanding the amount of energy in the universe: If you built a large nuclear reactor every second since the universe began roughly 15 billion years ago, you would equal the total power of merely one sun-sized star. [And if you consider] that the total number of stars in all the galaxies is greater than the total number of grains of sand on all the beaches, and you might have a fuzzy grasp of the power in our universe. Of course, there’s also dark energy which accounts for the other 70 per cent of the energy in the universe. Clearly, analogies can only take you so far.”
~ Professor of Physics Chris McKee from the University of California, Berkeley
