David Fabricius
Encyclopedia
David Fabricius was a German
Germans
The Germans are a Germanic ethnic group native to Central Europe. The English term Germans has referred to the German-speaking population of the Holy Roman Empire since the Late Middle Ages....

 theologian who made two major discoveries in the early days of telescopic astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

, jointly with his eldest son, Johannes Fabricius
Johannes Fabricius
Johann Fabricius , eldest son of David Fabricius , was a Frisian/German astronomer and a discoverer of sunspots , independently of Galileo Galilei.-Biography:...

 (1587–1615).

David Fabricius (Latinization of his proper name David Faber or David Goldschmidt) was born at Esens, Lower Saxony, and served as pastor for small towns near his birthplace in Frisia
Frisia
Frisia is a coastal region along the southeastern corner of the North Sea, i.e. the German Bight. Frisia is the traditional homeland of the Frisians, a Germanic people who speak Frisian, a language group closely related to the English language...

 (now northwest Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 and northeast Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

), at Resterhafe near Dornum
Dornum
Dornum is a village and a municipality in the East Frisian district of Aurich, in Lower Saxony, Germany. It is situated near the North Sea coast, approx...

 in 1584 and at Osteel in 1603. As was common for churchmen of the day, he dabbled in science: his particular interest was astronomy.

Fabricius discovered the first known periodic variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...

 (as opposed to cataclysmic variables, such as nova
Nova
A nova is a cataclysmic nuclear explosion in a star caused by the accretion of hydrogen on to the surface of a white dwarf star, which ignites and starts nuclear fusion in a runaway manner...

s and supernova
Supernova
A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...

s), Mira
Mira
Mira also known as Omicron Ceti , is a red giant star estimated 200-400 light years away in the constellation Cetus. Mira is a binary star, consisting of the red giant Mira A along with Mira B. Mira A is also an oscillating variable star and was the first non-supernova variable star discovered,...

, in August of 1596. At first he believed it to be "just" another nova, as the whole concept of a recurring variable did not exist at the time. When he saw Mira brighten again in 1609, however, it became clear that a new kind of object had been discovered in the sky.

Two years later, his son Johannes Fabricius
Johannes Fabricius
Johann Fabricius , eldest son of David Fabricius , was a Frisian/German astronomer and a discoverer of sunspots , independently of Galileo Galilei.-Biography:...

 (1587–1615) returned from university in the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 with telescopes that they turned on the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

. Despite the difficulties of observing the sun directly, they noted the existence of sunspot
Sunspot
Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions. They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature....

s, the first confirmed instance of their observation (though unclear statements in East Asian annals suggest that Chinese
Chinese people
The term Chinese people may refer to any of the following:*People with Han Chinese ethnicity ....

 astronomers may have discovered them with the naked eye previously, and Fabricius may have noticed them himself without a telescope a few years before). The pair soon invented camera obscura
Camera obscura
The camera obscura is an optical device that projects an image of its surroundings on a screen. It is used in drawing and for entertainment, and was one of the inventions that led to photography. The device consists of a box or room with a hole in one side...

 telescopy so as to save their eyes and get a better view of the solar disk, and observed that the spots moved. They would appear on the eastern edge of the disk, steadily move to the western edge, disappear, then reappear at the east again after the passage of the same amount of time that it had taken for it to cross the disk in the first place. This suggested that the Sun rotated
Rotation
A rotation is a circular movement of an object around a center of rotation. A three-dimensional object rotates always around an imaginary line called a rotation axis. If the axis is within the body, and passes through its center of mass the body is said to rotate upon itself, or spin. A rotation...

 on its axis, which had been postulated before but never backed up with evidence. Johannes published Maculis in Sole Observatis, et Apparente earum cum Sole Conversione Narratio ("Narration on Spots Observed on the Sun and their Apparent Rotation with the Sun") in June of 1611. Unfortunately, the book remained obscure and was eclipsed (so to speak) by the independent discoveries of and publications about sunspots by Christoph Scheiner
Christoph Scheiner
Christoph Scheiner SJ was a Jesuit priest, physicist and astronomer in Ingolstadt....

 in January 1612 and Galileo Galilei
Galileo Galilei
Galileo Galilei , was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism...

 in March 1612.

Besides these two discoveries, little else is known about David Fabricius except his unusual manner of death, which occurred at Osteel
Brookmerland
Brookmerland is a Samtgemeinde in the district of Aurich, in Lower Saxony, Germany. It is situated southeast of Norden. Its seat is in the village Marienhafe....

: after denouncing a local goose thief from the pulpit, the accused man struck him in the head with a shovel and killed him.

Legacy

Copies of a map he made of Frisia in 1589 are also still extant. He is also name-checked in Jules Verne
Jules Verne
Jules Gabriel Verne was a French author who pioneered the science fiction genre. He is best known for his novels Twenty Thousand Leagues Under the Sea , A Journey to the Center of the Earth , and Around the World in Eighty Days...

's From the Earth to the Moon as someone who claimed to have seen lunar inhabitants through his telescope, though that particular fact is merely part of Verne's fiction. The large (90-kilometer) crater Fabricius
Fabricius (crater)
Fabricus is a lunar impact crater that is located within the northeast part of the walled plain Janssen. Attached to the north-northwest rim is the slightly larger cater Metius. Fabricius has multiple central peaks that rise to 0.8 km, with a rugged rise to the northwest running north–south. The...

 in the Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...

's southern hemisphere is named after David Fabricius. In 1895 a monument was erected to his memory in the churchyard at Osteel where he was pastor
Pastor
The word pastor usually refers to an ordained leader of a Christian congregation. When used as an ecclesiastical styling or title, this role may be abbreviated to "Pr." or often "Ps"....

from 1603 until 1617.

External links

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