Andrew Ellicott Douglass
Andrew Ellicott Douglass (born July 5, 1867 in Windsor , Vermont , † March 20, 1962 in Tucson , Arizona ) was an American astronomer and is considered the founder of dendrochronology .
Live and act
Leonardo da Vinci already suspected that the annual rings of trees reflect the climatic growth conditions in an annual rhythm. In the 17th and 18th centuries, this became more commonly known and used to determine the age of trees. At the end of the 19th century, Arthur von Seckendorff-Gudent "overlapped" the tree ring sequences of different trees, but only Douglass succeeded in determining the age of dead and blocked tree samples using the "overlap" technique (cross-dating method). Douglass was the first to drill into trees in order to obtain information about the climatic growth conditions and the assumed relationship to solar activity by means of the thickness of the tree rings .
Douglass first worked at the Harvard College Observatory . After meeting Percival Lowell , he conducted primarily Mars observations at the Lowell Observatory in Flagstaff from 1894 to 1906 and began the first research into the relationship between tree rings and solar activity. He could not prove his theory, but he laid the scientific foundation for the Laboratory of Tree-Ring Research , a scientific collection of wooden annual rings. From 1906 Douglass taught in Tucson and worked on the systematic expansion of dendrochronology. In 1918 he began dating tree samples from ancient Aztec ruins, and in 1929 he was able to assign a 585-year-old annual ring chronology to the yellow pine ( Pinus Ponderosa ) archaeological finds. Between 1919 and 1936 his Climate Cycles and Tree Growth appeared in three volumes . From 1923 to 1937 he was director of the newly established steward observatory at the University of Arizona . After his retirement he wrote many articles on dendrochronology and climate research .
In 1941 he was elected a member of the American Philosophical Society . The asteroid (2196) Ellicott and 2004 the asteroid (15420) Aedouglass were named after him. A moon crater and a Martian crater are also named after him.
literature
- George Ernest Webb: Tree Rings and Telescopes. The Scientific Career of AE Douglass. University of Arizona Press Tucson, Tucson AZ 1983, ISBN 0-8165-0798-8 .
Web links
- Wiener Zeitung : Talkative Tree Rings - The Birth of Dendrochronology from Mars Observation ( Memento from March 5, 2016 in the Internet Archive )
- AE Douglass publications in the Astrophysics Data System
- George E. Webb: AE Douglass and the canals of Mars. In: The Astronomy Quarterly. Vol. 3, No. 9, 1979, pp. 27-37, doi : 10.1016 / S0364-9229 (79) 80003-2 .
Individual evidence
- ↑ Bild der Wissenschaft 11/2019, p. 40, Desiree Karge: Die silent Chronografen
- ^ Member History: Andrew E. Douglass. American Philosophical Society, accessed July 20, 2018 .
- ↑ Minor Planet Circ. 52324
- ↑ Andrew Ellicott Douglass in the IAU's Gazetteer of Planetary Nomenclature (WGPSN) / USGS
- ↑ Andrew Ellicott Douglass in the IAU's Gazetteer of Planetary Nomenclature (WGPSN) / USGS
| personal data | |
|---|---|
| SURNAME | Douglass, Andrew Ellicott |
| BRIEF DESCRIPTION | American astronomer |
| DATE OF BIRTH | July 5, 1867 |
| PLACE OF BIRTH | Windsor , Vermont |
| DATE OF DEATH | March 20, 1962 |
| Place of death | Tucson , Arizona |