Friedrich II. Graf von Hahn (July 27, 1742 – October 9, 1805) was a German nobleman, a philosopher and astronomer born in
Neuhaus, Holstein,
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
. He suggested the
Doppler effect before
Doppler.
Career
Observatory
In 1793 Von Hahn started the construction of a private observatory, the first in
Mecklenburg
Mecklenburg (; nds, label= Low German, Mękel(n)borg ) is a historical region in northern Germany comprising the western and larger part of the federal-state Mecklenburg-Western Pomerania. The largest cities of the region are Rostock, Schweri ...
, which was well equipped.
He owned some of the largest mirrors made by
William Herschel
Frederick William Herschel (; german: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline ...
and precision instruments for determining the position of stars. He used his instruments in order to observe various
stars
A star is an astronomical object comprising a luminous spheroid of plasma held together by its gravity. The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night, but their immense distances from Earth ma ...
, including the
sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
,
planets, and
nebulae
A nebula ('cloud' or 'fog' in Latin; pl. nebulae, nebulæ or nebulas) is a distinct luminescent part of interstellar medium, which can consist of ionized, neutral or molecular hydrogen and also cosmic dust. Nebulae are often star-forming region ...
.
Discoveries and observations
Von Hahn spent a significant amount of time observing the nebula
NGC 3242, originally discovered by William Herschel. He documented the change in position and shape of the nebula over the course of a year. He also observed the
Mira star system, which he had erroneously thought to be a nebula. The discovery Von Hahn in best known for is his 1800 discovery of the central star in
the Ring Nebula M 57, in the constellation,
Lyra
Lyra (; Latin for lyre, from Greek ''λύρα'') is a small constellation. It is one of the 48 listed by the 2nd century astronomer Ptolemy, and is one of the modern 88 constellations recognized by the International Astronomical Union. Lyra wa ...
.
This discovery contributed to
Antoine Darquier de Pellepoix's discovery of the nebula 21 years earlier.
Death and memory
He died in
Remplin
Remplin is a village and a former municipality in the Mecklenburgische Seenplatte district, in Mecklenburg-Vorpommern, Germany. Since 7 June 2009, it is part of the municipality Malchin.
Palace Complex
The town includes the remains of a once lar ...
,
Mecklenburg
Mecklenburg (; nds, label= Low German, Mękel(n)borg ) is a historical region in northern Germany comprising the western and larger part of the federal-state Mecklenburg-Western Pomerania. The largest cities of the region are Rostock, Schweri ...
, Germany on October 9, 1805 at the age of 63. After his death, his son, the "theatrical count" and father of author
Ida, Countess von Hahn-Hahn
Countess Ida von Hahn-Hahn (german: link=no, Ida Gräfin von Hahn-Hahn; 22 June 1805 – 12 January 1880) was a German author from a wealthy family who lost their fortune because of her father's eccentric spending. She defied convention by living ...
, squandered his fortune and all books and instruments were sold. The best instruments were bought by
Friedrich Wilhelm Bessel
Friedrich Wilhelm Bessel (; 22 July 1784 – 17 March 1846) was a German astronomer, mathematician, physicist, and geodesist. He was the first astronomer who determined reliable values for the distance from the sun to another star by the method ...
for the new observatory in
Königsberg
Königsberg (, ) was the historic Prussian city that is now Kaliningrad, Russia. Königsberg was founded in 1255 on the site of the ancient Old Prussian settlement ''Twangste'' by the Teutonic Knights during the Northern Crusades, and was name ...
. One instrument is on display in the
Deutsches Museum
The Deutsches Museum (''German Museum'', officially (English: ''German Museum of Masterpieces of Science and Technology'')) in Munich, Germany, is the world's largest museum of science and technology, with about 28,000 exhibited objects from ...
in Munich. His herschelian telescope was acquired in 1812 by the Neapolitan astronomer, Federigo Zuccari, for the new
Capodimonte Observatory
The Astronomical Observatory of Capodimonte ( it, Osservatorio Astronomico di Capodimonte, italic=no) is the Neapolitan department of Istituto Nazionale di Astrofisica (National Institute for Astrophysics, INAF), the most important Italian institu ...
.
Now th
mirrorof this telescope is part of the Observator
Museumcollection.
He is honoured together with
Otto Hahn
Otto Hahn (; 8 March 1879 – 28 July 1968) was a German chemist who was a pioneer in the fields of radioactivity and radiochemistry. He is referred to as the father of nuclear chemistry and father of nuclear fission. Hahn and Lise Meitner ...
by the lunar crater
Hahn.
References
External links
Remplin Observatory
{{DEFAULTSORT:Hahn, Friedrich von
1742 births
1805 deaths
18th-century German astronomers
German philosophers
People from the Duchy of Holstein
German male writers