Gustav Niessl von Mayendorf (26 April 1839 in

Verona Verona ( , ; vec, Verona or ) is a city on the Adige River in Veneto, Northern Italy, Italy, with 258,031 inhabitants. It is one of the seven provincial capitals of the region. It is the largest city Comune, municipality in the region and the ...

– 1 September 1919 in Hütteldorf, Vienna; often cited as G. von Niessl), was an Austrian

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

and

mycologist Mycology is the branch of biology concerned with the study of fungus, fungi, including their genetics, genetic and biochemistry, biochemical properties, their Taxonomy (biology), taxonomy and ethnomycology, their use to humans, including as a so ...

. Niessl, the son of an artillery officer, studied at the Polytechnic in Vienna in 1857 and became assistant to practical geometry. In 1859 he took the chair of practical geometry at

German Technical University in Brno German Technical University in Brno (German: ''Deutsche Technische Hochschule Brünn'') was a technical university in Brno. It existed from 1849 to 1945 and instruction was in German. At the time, Brno was a multicultural city with both Czech and ...

, where he became a full professor in 1860 and later taught applied geometry, astronomy and higher

geodesy Geodesy ( ) is the Earth science of accurately measuring and understanding Earth's figure (geometric shape and size), orientation in space, and gravity. The field also incorporates studies of how these properties change over time and equivale ...

. He became the director in 1868/1869. After this technical college, he was its rector in 1877/78 and 1888/89. In 1907 he retired (and in the same year received an

honorary doctorate An honorary degree is an academic degree for which a university (or other degree-awarding institution) has waived all of the usual requirements. It is also known by the Latin phrases ''honoris causa'' ("for the sake of the honour") or ''ad hon ...

). For several decades he was secretary of the Natural Science Society in Brno. Niessl was first engaged in geodesy. As an astronomer, he was employed with Niessl meteor orbits and also wrote the article in the ''Enzyklopädie der mathematischen Wissenschaften'' (''Encyclopedia of Mathematical Sciences'') (1907). Niessl was also a significant mycologist and mushroom collector, whose collection is currently housed at the Botanical State Collection Munich. He was regarded as an expert in the flora of

Moravia Moravia ( , also , ; cs, Morava ; german: link=yes, Mähren ; pl, Morawy ; szl, Morawa; la, Moravia) is a historical region in the east of the Czech Republic and one of three historical Czech lands, with Bohemia and Czech Silesia. The me ...

and

Silesia Silesia (, also , ) is a historical region of Central Europe that lies mostly within Poland, with small parts in the Czech Republic and Germany. Its area is approximately , and the population is estimated at around 8,000,000. Silesia is split ...

, and had close contact with the botanist Gottlob Ludwig Rabenhorst. Two fungal species were named after him. He was particularly concerned with microscopic

sac fungi Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defi ...

, slime molds, and rusts. From 1904 until his death, he was a corresponding member of the Austrian Academy of Sciences. He was also a member of the Austrian Commission for International Geodesy and the Austrian Patent Court.

References

{{DEFAULTSORT:Mayendorf, Gustav Niessl von 1839 births 1919 deaths Austrian mycologists 19th-century Austrian astronomers 20th-century Austrian astronomers