Heaven Police
The Sky Police was an international cooperation of numerous European observatories for the systematic search for suspected or "lost" celestial bodies . It was founded in 1800 at the second European astronomical congress.
Already at the first astronomical congress in 1798, the French mathematician Jérôme Lalande had requested a coordinated search for which each participating observatory was to take over a certain part of the sky.
Organization tasks
The most important task of the Sky Police was the planned survey of the starry sky around the ecliptic in order to find a small planet suspected between Mars and Jupiter orbits . The existence of this celestial body was u. a. inferred from the Titius-Bode series , a geometric series of orbital radii from Mercury to Uranus that has a gap at 2.8 astronomical units . Already Kepler had in his heaven harmony postulated an unknown planet there.
The second area of work was the addition and improvement of the only incomplete star catalogs - a prerequisite for identifying new objects with certainty and being able to calculate their exact path later .
The observatories active in the organization were spread across all major European countries, with a focus on Germany , Austria and Italy . The Astronomical Society , whose founding members included Franz Xaver von Zach and Johann Hieronymus Schroeter , also provided several observers .
For the coordinated search of the "sky police", the area around the ecliptic (i.e. the area around the signs of the zodiac ) was divided into 24 sections. Each of these sections was assigned to an observatory that would search it for the planet. Wilhelm Olbers , the discoverer of minor planets No. 2 and 4, and Lalande, however, advocated more extensive search fields in some places in the sky.
Search for the first minor planets
The initiators of the establishment were the German-Austrian astronomer Franz Xaver von Zach , who had also organized the first astronomical congress in Gotha in 1798 , and the amateur astronomer Johann Hieronymus Schroeter , who had a very powerful observatory with professional instrumentation north of Bremen in Lilienthal . A dozen European observatories took part in the Sky Police from the beginning in order to search for the "eighth planet" postulated by Johannes Kepler in a coordinated manner.
The founding of the research group can also be explained by the state of the communication structures in the natural sciences at that time, the discoveries of which have hardly been made known through publication organs, but mainly in the correspondence of scientists.
The new surveillance organization led to the discovery of the first and largest planetoid (1) Ceres by the Sicilian Piazzi at the turn of the year 1800/1801 - albeit by a happy coincidence . The first mutual success of the group was the difficult recovery of the Ceres at the end of 1801 after its long orbit behind the sun, for the purpose of which Gauss had developed the theory of orbit determination . The sighting itself took place almost simultaneously by FX Zach (Gotha) and Wilhelm Olbers (Bremen). Soon afterwards, Olbers succeeded in discovering the second planetoid (2) Pallas and in 1807 that of (4) Vesta ; In 1804 Schröter's assistant Harding discovered the third minor planet (3) Juno . Olbers' successes are based u. a. that he focused on regions of the constellations Virgo and Whale.
Better star catalogs
The United Astronomical Society , which was founded shortly before the Sky Police, also discussed further research projects . This initially loose association of leading astronomers continued u. a. the aim of developing more precise star catalogs and better celestial basics of the coordinate systems. The astronomical interest of the general public and the dissemination of relevant specialist knowledge should also be promoted.
The demand for more precise star catalogs arose for two reasons:
- the need to measure the positions of even weak (no longer freely visible) stars in the sky in order to be able to discover small moving celestial bodies in the first place,
- good definition of celestial coordinates as a basis for the exact orbit determination of the newly discovered celestial bodies.
While working on an excerpt from his star catalog, G. Piazzi, director of the Palermo observatory , discovered the first minor planet, Ceres. The problems that soon emerged in identifying and keeping evidenced celestial bodies accelerated these efforts to create better star maps.
Later research goals
In the early 19th century , the systematic monitoring of variable and " new " stars began, organized primarily by German astronomers (see also Argelander ). For the long-term measurement of precise star locations , similar to the planetoid search from 1800 to 1807, various “zone programs” were organized and assigned to the individual observatories for processing. This resulted in high-quality star catalogs and celestial atlases on which future discoveries of minor planets and comets could be based.
The concept of survey and some fog catalogs developed around 1850 from the sky surveillance organized by division of labor . As the best-known star catalog of the 19th century, the Bonn survey with 300,000 stars was tackled, later supplemented by zone companies of some more southern observatories organized according to geographical latitude . As early as the end of the 18th century, the fog index in the Messier catalog had been created for the quicker identification of new comets . a. William Herschel until 1802 - was greatly expanded.
An organization similar to the Zach'schen Himmelspolizey was sought around 1900 for the further search for small bodies of the solar system, but only came to fruition to a limited extent. Of the astronomers working there, the Austrian Johann Palisa and the South German Max Wolf should be mentioned in particular . The former organized (in addition to its 123 discovered asteroids ) the systematic determination of the orbit of the new or rediscovered celestial bodies, the latter introduced photographic surveillance methods into astronomy and was even able to discover over 200 asteroids.
See also
literature
- Peter Brosche: The Duchess' astronomer. Life and work of Franz Xaver von Zach 1754-1832 . 2nd revised and expanded edition. German, Frankfurt am Main 2009, ISBN 978-3-8171-1832-8 , ( Acta historica astronomiae 12).
- Volker Witt: Memories of the Lilienthal observatory . In: Sterne und Weltraum December 2006, pp. 84–89, (Founding of the Sky Police, observations by Zach, Olbers and Harding).
- Hans Kraemer (ed.): Universe and humanity. History of the study of nature and the utilization of natural forces in the service of peoples . Volume 3. Bong, Berlin a. a. 1903, ZDB -ID 245182-7 , Chapter: Planets.
Individual evidence
- ^ GD Roth, Die Planetoiden . Orion books 137/1960, pp. 13-15
- ↑ Trier observatory 2008, dwarf planets ( memento of the original from March 8, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
