Paul Oswald Ahnert

Paul Oswald Ahnert (born November 22, 1897 in Chemnitz , † February 27, 1989 in Sonneberg ) was a German astronomer .

He is well known among specialist and amateur astronomers as the editor of the astronomical yearbook Calendar for Star Friends , also known as the Ahnert for short . His main research area was the variable stars . As part of the Sonneberg Sky Monitoring - a long-term research project for the observation and photographic monitoring of variable stars - he was involved in many discoveries at the Sonneberg Observatory . His series of observations on sunspot statistics are also of scientific value.

Life

Paul Ahnert was born in Chemnitz in the Kingdom of Saxony . Even as a child he was impressed by the starry sky and suggestions from his natural history teacher prompted him to take a closer look at questions of astronomy . From 1912 to 1917 he went to the teacher training seminar in Frankenberg to become an elementary school teacher. It was then that he began observing the sky with binoculars. He experienced the end of the First World War as a soldier at the front. After returning from the war he became an elementary school teacher in Burkhardtsdorf near Chemnitz. For more intensive astronomical celestial observations, he bought a small, powerful telescope and built a small private observatory . He was most interested in variable stars and the sun . His first publication appeared in 1923 in the " Astronomische Nachrichten " (AN 219, pp. 165-170) on long-period variable stars that he had observed from his private observatory.

Through a series of observations on variable stars that were little known at the time, he gained recognition among specialist astronomers until the early 1930s. But he would probably have remained a teacher in the long term if the fascist seizure of power in 1933 had not thrown him out of his life. As a committed SPD comrade, Paul Ahnert spent four months in a concentration camp , was banned from working and then had to make a living for his family with poorly paid odd jobs. Word of the difficult life situation of the ambitious amateur astronomer got around among star friends and took a happy turn in 1938. Cuno Hoffmeister took him to Sonneberg and kept him busy at the Sonneberg observatory. Later on, with the support of Paul Guthnick , Hoffmeister even managed to get Paul Ahnert back into the civil service - contrary to the legal regulations - and allowed to work as an observer and evaluator in the context of the Sonneberg sky surveillance. In 1939, through intensive studies of the distribution of the Mira stars , he discovered the relationship between their age-dependent location in certain regions of the Milky Way . In addition to observing the sky, he also worked in collaboration with Rudolf Brandt on the development of observation and evaluation instruments. It is also noteworthy that Ahnert must be regarded as the discoverer of the solar wind, as explained in more detail by Wilfried Schöder. Ahnert was able to make the decisive observations of the comet's tails on the comet Whipple-Fedke (1942 g). His results were expanded upon by considerations by Cuno Hoffmeister.

Cuno Hoffmeister succeeded in maintaining research activities in Sonneberg during the Second World War and in ensuring the continued employment of his employees even afterwards under Soviet occupation . Paul Ahnert therefore stayed in Sonneberg as an astronomer after the war. From 1945, the astronomer Eva Rohlfs , whom he married in 1952 and whose early death he had to lament in 1954, also worked at the observatory . His first marriage to Rose geb. Ungibauer was divorced in 1951. From 1948 he published the “ Calendar for Star Friends ” . He also published observation instructions and an astronomical-chronological table for amateur astronomers, with which, for example, solar and lunar eclipses and planetary positions over six millennia can be determined with astonishingly high accuracy and very little computational effort. 1957 awarded him Friedrich Schiller University of Jena the honorary doctorates , honoring his achievements.

With the support of his third wife Elisabeth, he remained the editor of the “Calendar for Star Friends” until he was 90 and corresponded with many specialist and amateur astronomers in East and West. But he was also active at the observatory beyond his 80th birthday and regularly observed the starry sky with a reflector telescope specially provided for him. In honor of his life's work, the planetoid (3181) was named Ahnert in July 1985 . Only in 1988 did he hand over the publication of the “Calendar for Star Friends” to the Sonneberg astrophysicist Rainer Luthardt. Paul Ahnert died at the age of 91 after a short, serious illness in Sonneberg.

Honors

• The asteroid (3181) Ahnert was named after Paul Ahnert.

Individual evidence

1. ^ "Who first discovered the Solar Wind?", Contributions to the history of geophysics and cosmic physics, IX, issue 3, 2008

bibliography

• The variable stars of the northern Milky Way. T.4. (edited by C. Hoffmeister and P. Ahnert) Publications of the Sonneberg Observatory (1947)
• The change of light from 46 bright mira stars. Akademie-Verlag Berlin (1954)
• Astronomical-chronological tables for the sun, moon and planets. Johann Ambrosius Barth Verlag (1960, 1961, 1965)
• Observation objects for amateur astronomers. JA Barth Verlag Leipzig (1961 and 1968)
• Moon map in 25 sections. (as editor of the new edition of this work by WG Lohrmann ) JA Barth Verlag, Leipzig (1963)
• Astronomical treatises. (together with C. Hoffmeister) JA Barth Verlag Leipzig (1965)
• Little practical astronomy. Auxiliary tables and observation objects. JA Barth Verlag Leipzig (1974 and 1986) ISBN 3335000005
• Calendar for star lovers. Astronomical yearbook. JA Barth Verlag Leipzig (40 volumes: 1948–1988; publisher: P. Ahnert)

Web links

• Publications by P. Ahnert in the Astrophysics Data System