Graph of radiocarbon dating
Fifty, 20, or 100 years is a lot of time, wherein a lot can happen.
They are chronographs, recording clocks, by which the succeeding seasons are set down through definite imprints," he wrote in the pages of National Geographic.If a Bigtooth Maple were cut down on Mount Lemmon in 2016 and it had 400 rings, you would know the tree started growing in 1616. What if it's been used to build a home or a ship or a bonfire?The rings could still tell how many years the tree lived, but not necessarily when. He set out on a series of expeditions across the southwest to bridge the gap between contemporary wood and wood beams from the ruins of civilizations long gone."It can get us to within 20, 50, 100 years or so of dating accuracy." On the scale of the universe, 20, 50 or even 100 years is, for all intents and purposes, nothing. Our galaxy, the Milky Way, is slightly younger, at 13.2 billion years old.The Earth and our moon are both more than four-and-a-half billion years old.For decades, radiocarbon dating has been a way for scientists to get a rough picture of when once-living stuff lived.
The method has been revolutionary and remains one of the most commonly used dating methods to study the past. Pearson, an assistant professor of dendrochronology at the University of Arizona, studies the past lives of trees to better understand the history of civilizations.
Dendrochronology and radiocarbon dating have intertwined histories, she explains, with roots firmly planted at the UA.
A 1929 edition of National Geographic boasts, "The Secret Of The Southwest Solved By Talkative Tree Rings." The 35-page article, penned in whimsical prose, was written by Andrew Douglass, the UA scientist who invented tree ring science. In addition to his work as an astronomer at the UA's Steward Observatory, Douglass was the first to discover that tree rings record time.
In other words, life in the universe moves inconceivably slowly.
But for individual humans—and entire civilizations—it does not.
Sometimes a wood sample doesn't have enough tree rings or rings with growth patterns that match an already dated sample.