In
astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
, Durchmusterung or Bonner Durchmusterung (BD) is an
astrometric
Astrometry is a branch of astronomy that involves precise measurements of the positions and movements of stars and other celestial bodies. It provides the kinematics and physical origin of the Solar System and this galaxy, the Milky Way.
Histor ...
star catalogue
A star catalogue is an astronomical catalogue that lists stars. In astronomy, many stars are referred to simply by catalogue numbers. There are a great many different star catalogues which have been produced for different purposes over the years, ...
of the whole sky, compiled by the
Bonn
The federal city of Bonn ( lat, Bonna) is a city on the banks of the Rhine in the German state of North Rhine-Westphalia, with a population of over 300,000. About south-southeast of Cologne, Bonn is in the southernmost part of the Rhine-Ruhr r ...
Observatory in Germany from 1859 to 1903. The name comes from ('run-through examination'), a German word used for a systematic survey of objects or data. The term has sometimes been used for other astronomical surveys, including not only stars, but also the search for other celestial objects. Special tasks include celestial scanning in
electromagnetic wavelengths shorter or longer than
visible light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 te ...
waves.
Original catalog
The 44 years of work on the Bonner Durchmusterung (abbreviated BD), initiated by
Friedrich Argelander and largely carried out by his assistants, resulted in a catalogue of the positions and
apparent magnitude
Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's li ...
s of approximately 325,000 stars to apparent magnitude 9–10. The catalogue was accompanied by charts plotting the positions of the stars, and was the basis for the ''
Astronomische Gesellschaft Katalog
The ''Astronomische Gesellschaft Katalog'' (AGK) is an astrometric star catalogue. Compilation for the first version, AGK1, was started in 1861 by Friedrich Argelander and published between 1890 and 1954, listing 200 000 stars down to ninth m ...
'' (AGK) and ''
Smithsonian Astrophysical Observatory Star Catalog'' (SAO) catalogues of the 20th century. The BD star numbers are still used and allow the correlation of the work with modern projects.
The format of a BD number is exemplified by "BD−16 1591", which is the BD number of
Sirius
Sirius is the list of brightest stars, brightest star in the night sky. Its name is derived from the Ancient Greek language, Greek word , or , meaning 'glowing' or 'scorching'. The star is designated α Canis Majoris, Latinisation ...
. This number signifies that in the catalog, Sirius is the 1591st star listed in the
declination
In astronomy, declination (abbreviated dec; symbol ''δ'') is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system, the other being hour angle. Declination's angle is measured north or south of the ...
zone between −16 and −17 degrees, counting from 0 hours
right ascension
Right ascension (abbreviated RA; symbol ) is the angular distance of a particular point measured eastward along the celestial equator from the Sun at the March equinox to the (hour circle of the) point in question above the earth.
When paired w ...
.
Stellar positions and zone boundaries use an
equinox for the
epoch of B1855.0.
Extension
Many astronomical research projects—from studies of
celestial mechanics
Celestial mechanics is the branch of astronomy that deals with the motions of objects in outer space. Historically, celestial mechanics applies principles of physics (classical mechanics) to astronomical objects, such as stars and planets, to ...
and the
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar S ...
, up to the nascent field of
astrophysics
Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the h ...
—were made possible by the publication of the atlas and data of the Bonner Durchmusterung. However, a deficiency of the BD was that it did not cover the whole sky, because far southern stars are not visible from Germany.
This led the scientific community to supplement the BD with two additional astrometric surveys carried out by
observatories
An observatory is a location used for observing terrestrial, marine, or celestial events. Astronomy, climatology/meteorology, geophysical, oceanography and volcanology are examples of disciplines for which observatories have been constructed. His ...
located in the Southern Hemisphere:
Córdoba, Argentina
Córdoba () is a city in central Argentina, in the foothills of the Punilla Valley, Sierras Chicas on the Primero River, Suquía River, about northwest of Buenos Aires. It is the capital of Córdoba Province, Argentina, Córdoba Province a ...
, and
Cape Town
Cape Town ( af, Kaapstad; , xh, iKapa) is one of South Africa's three capital cities, serving as the seat of the Parliament of South Africa. It is the legislative capital of the country, the oldest city in the country, and the second largest ...
, South Africa. The Cordoba Durchmusterung (abbreviated CD, or, less commonly, CoD) was made visually (as was the BD), but the Cape Photographic Durchmusterung (CP or CPD) was conducted by the then-new photographic technique, which had just been shown to have sufficient accuracy. The southern stars are identified by CD and CPD numbers in a manner similar to the BD numbering system.
A few decades later, the positional accuracy of the Durchmusterung catalogues began to be insufficient for many projects. To establish a more exact reference system for the Bonner Durchmusterung, astronomers and
geodesists began to work on a fundamental
celestial coordinate system based on the
Earth's rotation axis
In astronomy, axial tilt, also known as obliquity, is the angle between an object's rotational axis and its orbital axis, which is the line perpendicular to its orbital plane; equivalently, it is the angle between its equatorial plane and orbit ...
, the vernal
equinox and the
ecliptic plane in the late 19th century. This astrometric project led to the ''
Catalogues of Fundamental Stars
The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference frame, which is a standard coordinate system for measuring positions of s ...
'' of the Berlin observatory, and was used as an exact coordinate frame for the BD and AGK. It was modernized in the 1920s (
FK3
The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference frame, which is a standard coordinate system for measuring positions of s ...
, mean accuracy ±1″), and in 2000 (
FK6
The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference frame, which is a standard coordinate system for measuring positions of st ...
, accuracy 0.1″) as successive steps of
cosmic geodesy. Together with
radioastronomical measurements, the FK6 accuracy was better than ±0.1″.
Modern counterparts
The ''
Hipparcos
''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial obj ...
'' satellite operated between 1989 and 1993 and observed around 118,000 stars over the whole sky. Three star catalogues were published from its data:
* ''
Hipparcos Catalogue'' (118,000 stars, average accuracy ±0.001″)
* ''
Tycho Catalogue
''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial obj ...
'' (about 1,050,000 stars, with accuracy ±0.03″)
* ''
Tycho-2 Catalogue
The Tycho-2 Catalogue is an astronomical catalogue of more than 2.5 million of the brightest stars.
Catalogue
The astrometric reference catalogue contain positions, proper motions, and two-color photometric data for 2,539,913 of the brightes ...
'' (about 2,500,000 stars), which was improved for
double star
In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes.
This occurs because the pair either forms a binary star (i.e. a bi ...
effects and proper motions using the
Astrographic Catalogue observations.
The ''
Gaia
In Greek mythology, Gaia (; from Ancient Greek , a poetical form of , 'land' or 'earth'),, , . also spelled Gaea , is the personification of the Earth and one of the Greek primordial deities. Gaia is the ancestral mother—sometimes parthenog ...
''
space observatory
A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launched ...
, launched in December 2013, has catalogued a billion stars with an accuracy down to 20
microarcsecond
A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The n ...
s (0.00002″).
References
Further reading
*
External links
Bonner Durchmusterung (Argelander 1859–1862)(clicking on "bd.gz" downloads the gzipped 10.1MB catalogue)
Cordoba Durchmusterung (Thome 1892–1932)(clicking on "cd.dat.gz" downloads the gzipped 19MB catalogue) (note: the extension might have to be removed with some text editor before opening)
Cape Photographic Durchmusterung (Gill+ 1895–1900)(clicking on "cpd.dat.gz" downloads the gzipped 14.1MB catalogue) (note: the extension might have to be removed with some text editor before opening)
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Astronomical catalogues
Astronomical catalogues of stars
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