The partial becomes complete; the crooked, straight; the empty, full; the worn out, new.
The universe seems vast, distant, and unknowable. It is, for example, unimaginably large and old: The number of stars in our galaxy alone exceeds 100 billion, and the Earth is 4.5 billion years old. In the eyes of the universe, we’re nothing. (…)
Clearly, our brains are not built to handle numbers on this astronomical scale. While we are certainly a part of the cosmos, we are unable to grasp its physical truths. (…) However, there actually are properties of the cosmos that can be expressed at the scale of the everyday. (…)
It turns out that there is one supernova, a cataclysmic explosion of a star that marks the end of its life, about every 50 years in the Milky Way. The frequency of these stellar explosions fully fits within the life span of a single person, and not even a particularly long-lived one. So throughout human history, each person has likely been around for one or two of these bursts that can briefly burn brighter than an entire galaxy.
On the other hand, while new stars are formed in our galaxy at a faster rate, it is still nice and manageable, with about seven new stars in the Milky Way each year. So, over the course of an average American lifetime, each of us will have gone about our business while nearly 550 new stars were born.
photo { 美撒guo }
