Age of the Earth: A Very Deep Question
Part 1: Naturalists and Chronologists
Advances in science are too often wrongly portrayed as the work of one person or a few individuals battling in the name of modern science against the darkness of ignorance and narrow-minded religion. How scientific understanding changes, as illustrated in early attempts to understand the earth’s age, debunks the commonplace “science versus religion” perception. This historical episode also illustrates that many individuals, over long periods of time and in strange ways, contributed to our current knowledge of the earth’s age. Examining the evidence and arguments put forward for the earth’s age will help you better understand how science works and the important science idea that the earth is very old.
Read Early Efforts to Understand the Earth’s Age: Naturalists and Chronologists
Part 2: Deep Time
Beginning in the 1850s, over a century’s worth of work was needed to convince most scientists by the 1950s that the earth was very old. Another century of work, and hard-earned new knowledge from various scientific disciplines, was required to provide convincing evidence that our earth is several billion years old. Today, the phrase ‘deep time’ is often used when referring to the staggering and difficult to grasp age of the earth. The modern estimate of the earth’s age, determined by uranium-lead radioactive dating of earth materials and meteorites from the asteroid belt (thought to have formed at approximately the same time as earth), is about 4.5 billion years. Science textbooks often cite that number, but hide the extensive debate that took place regarding how knowledge of the earth should be sought, how data should be interpreted, and how knowledge from various scientific disciplines is expected to cohere. In doing so, they distort how science works, and make science careers appear far less than the creative and interesting profession than it is.