The Sternwarte Düsseldorf (a.k.a. Sternwarte Bilk, Sternwarte Charlottenruhe; Bilk Observatory or Düsseldorf-Bilk Observatory in English) in
Düsseldorf-Bilk was a private observatory founded in 1843 by
Johann Friedrich Benzenberg.
The observatory's main feature was a
refracting telescope
A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens (optics), lens as its objective (optics), objective to form an image (also referred to a dioptrics, dioptric telescope). The refracting telescope d ...
with 1800mm
focal length
The focal length of an Optics, optical system is a measure of how strongly the system converges or diverges light; it is the Multiplicative inverse, inverse of the system's optical power. A positive focal length indicates that a system Converge ...
. After Benzenberg's death the
observatory
An observatory is a location used for observing terrestrial, marine, or celestial events. Astronomy, climatology/meteorology, geophysics, oceanography and volcanology are examples of disciplines for which observatories have been constructed.
Th ...
was bequeathed to the city of
Düsseldorf
Düsseldorf is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in the state after Cologne and the List of cities in Germany with more than 100,000 inhabitants, seventh-largest city ...
. It was destroyed by bombing in 1943.
Between 1852 and 1890,
C. Robert Luther discovered 24
asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...
s there, from
Thetis
Thetis ( , or ; ) is a figure from Greek mythology with varying mythological roles. She mainly appears as a sea nymph, a goddess of water, and one of the 50 Nereids, daughters of the ancient sea god Nereus.
When described as a Nereid in Cl ...
, discovered on April 17, 1852, to
Glauke, discovered February 20, 1890. These asteroids and
planetoids are called ''the 24 Düsseldorf planets''. The asteroid
4425 Bilk is named in honour of the observatory.
Near its original location, a benchmark was erected, displaying the observatory's burnt-out telescope.
File:bst-close.jpg, Benchmark
File:bst-durch.jpg, view through the tube
File:bst-dist.jpg, front view
File:bst-schild.jpg, information plate
See also
*
List of astronomical observatories
This is a partial list of astronomical observatories ordered by name, along with initial dates of operation (where an accurate date is available) and location. The list also includes a final year of operation for many observatories that are no lon ...
References
Astronomical observatories in Germany
Buildings and structures in Düsseldorf
Tourist attractions in Düsseldorf
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