This is the first in a series of brief posts about facts I find interesting and/or surprising. The intent is to keep these posts brief but to provide links to detailed references for those interested in researching the topic further.
Milky way and rocky coast shot taken at night in New Zealand, long exposure about 2-3 minutes with high ISO.
Prior to the 19th century, estimates for the age of the earth and, indeed, the universe ranged from a few thousand years to a few million years. These estimates had little basis in empirical or scientifically-derived evidence. In the 19th and early 20th centuries, scientists began promoting the notion of the universe being infinite in size and time. In fact, readers from my generation likely remember learning this in grade school even as recently as the 1970s.
Astrophysics has come a long way over the past 100 years and, especially over the past few decades. There have been monumental advancements in technology that allows us to explore the far depths of our known universe. Scientists, based on multiple independent techniques that corroborate one another, now believe the universe to be 13.8 billion years old. Before that, we have no visibility. That is the extent of the “oldest light” we are able to see and trace back to a metaphorical “big bang” event before which there was nothing.
As a scientist myself, I acknowledge the fact that our theories are models that we continually refine as we make new discoveries; I’m certain that our children’s children will be taught an entirely different model of the universe than we were taught. While we may never reach the complete answer, we can strive to continually converge on it. That, after all, is the essence of science.
Sources:
Against the Herd 