# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Astro*Dictionary by Michael Erlewine





1 article for "Douglass, Andrew Ellicott"

Douglass, Andrew Ellicott [Astro*Index]

(1867-1962) American astronomer. Born at Windsor, Vermont; died at Tucson, Arizona.

He worked at Lowell Observatory, in Arizona and, in 1906, became a member of the faculty of the University of Arizona. His interest in the sun spurred an interest in climate. The dry climate of Arizona preserved ancient wood which shows a pattern of tree rings which vary in width. This variation reflects seasons which are wetter or drier than an average, and analysis permits one to date any piece of wood by noting how its pattern fit into a broader time-series. This system of dendrochronology was developed by 1920 and has provided a delicate method of dating recent archaelogical remnants.



Astro*Index Copyright © 1997 Michael Erlewine