1775 Zimmerwald, provisional designation , is a stony Eunomian
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 ...
and
slow rotator from the middle region of the
asteroid belt
The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids ...
, approximately 10 kilometers in diameter. It was discovered on 13 May 1969, by Swiss astronomer
Paul Wild at
Zimmerwald Observatory
The Zimmerwald Observatory () is an astronomical observatory owned and operated by the AIUB, the Astronomical Institute of the University of Bern. Built in 1956, it is located at Zimmerwald, 10 kilometers south of Bern, Switzerland.
Numerous com ...
near Bern, Switzerland.
It is named for the village of
Zimmerwald
Zimmerwald () was an independent municipality in the Canton of Bern, Switzerland until 31 December 2003. It is located on a hill in the proximity of the city of Bern in the Bernese Mittelland. On 1 January 2004 Zimmerwald united with the municipa ...
, where the discovering observatory is located.
Orbit and classification
''Zimmerwald'' is a member of the
Eunomia family The Eunomia or Eunomian family () is a large asteroid family of S-type asteroids named after the asteroid 15 Eunomia. It is the most prominent family in the intermediate asteroid belt and the 6th-largest family with nearly six thousand known member ...
, a large group of mostly stony
S-type asteroid
S-type (stony-type or silicaceous-type) asteroids are asteroids with a spectral type that is indicative of a siliceous (i.e. stony) mineralogical composition, hence the name. They have relatively high density. Approximately 17% of asteroids are ...
s and the most prominent family in the intermediate main-belt, which is located between two prominent
Kirkwood gap
A Kirkwood gap is a gap or dip in the distribution of the semi-major axes (or equivalently of the orbital periods) of the orbits of main-belt asteroids. They correspond to the locations of orbital resonances with Jupiter. The gaps were first n ...
s. It orbits the Sun in the
central main-belt at a distance of 2.1–3.1
AU once every 4 years and 2 months (1,533 days). Its orbit has an
eccentricity
Eccentricity or eccentric may refer to:
* Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal"
Mathematics, science and technology Mathematics
* Off-Centre (geometry), center, in geometry
* Eccentricity (g ...
of 0.19 and an
inclination
Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object.
For a satellite orbiting the Eart ...
of 13
° with respect to the
ecliptic
The ecliptic or ecliptic plane is the orbital plane of Earth's orbit, Earth around the Sun. It was a central concept in a number of ancient sciences, providing the framework for key measurements in astronomy, astrology and calendar-making.
Fr ...
.
The first
precovery
In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of a celestial object in images or photographic plates predating its discovery, typically for the purpose of calculating a more accurate orbit. This ha ...
of ''Zimmerwald'' was taken at
Palomar Observatory
The Palomar Observatory is an astronomical research observatory in the Palomar Mountains of San Diego County, California, United States. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...
in 1949, extending the body's
observation arc
In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...
by 20 years prior to its official discovery observation at Zimmerwald. During the 1950s, it was also identified at
Heidelberg
Heidelberg (; ; ) is the List of cities in Baden-Württemberg by population, fifth-largest city in the States of Germany, German state of Baden-Württemberg, and with a population of about 163,000, of which roughly a quarter consists of studen ...
,
Goethe Link
Johann Wolfgang (von) Goethe (28 August 1749 – 22 March 1832) was a German polymath who is widely regarded as the most influential writer in the German language. His work has had a wide-ranging influence on Western literature, literary, Polit ...
and
McDonald Observatory
McDonald Observatory is an astronomical observatory located near unincorporated community of Fort Davis in Jeff Davis County, Texas, United States. The facility is located on Mount Locke in the Davis Mountains of West Texas, with additional faci ...
.
Physical characteristics
Rotation period
In May 2011, a rotational
lightcurve
In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...
of ''Zimmerwald'' was obtained by American astronomer
Robert Stephens
Sir Robert Graham Stephens (14 July 193112 November 1995) was an English actor in the early years of Britain's Royal National Theatre.
Early life
Stephens was born in Shirehampton, Bristol, in 1931, the eldest of three children of shipyard ...
at the Center for Solar System Studies, California, using photometric observations taken at the Santana and Goat Mountain observatories (). Lightcurve analysis gave a very long
rotation period
In astronomy, the rotation period or spin period of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the '' sidereal rotation period'' (or ''sidereal day''), i.e., the time that the objec ...
of hours with a change in brightness of 0.60
magnitude
Magnitude may refer to:
Mathematics
*Euclidean vector, a quantity defined by both its magnitude and its direction
*Magnitude (mathematics), the relative size of an object
*Norm (mathematics), a term for the size or length of a vector
*Order of ...
(). It is also suspected, that the body might be in a nonprincipal axis rotation, which is commonly known as "tumbling".
While the
slowest rotators have periods above 1000 hours, the majority of minor planets have periods
shorter than 20 hours.
Diameter and albedo
According to the surveys carried out by the Japanese
Akari
AKARI (ASTRO-F) was an infrared astronomy satellite developed by Japan Aerospace Exploration Agency, in cooperation with institutes of Europe and Korea. It was launched on 21 February 2006, at 21:28 UTC (06:28, 22 February JST) by M-V rocket ...
satellite and NASA's
Wide-field Infrared Survey Explorer
Wide-field Infrared Survey Explorer (WISE, List of observatory codes, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy Space observatory, space telescope in the Explorers Program launched in December 2009.. . WISE L ...
with its subsequent
NEOWISE
Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and MIDEX-6) was a NASA infrared astronomy space telescope in the Explorers Program launched in December 2009.. . WISE discovered thousands of minor planets and nu ...
mission, ''Zimmerwald'' measures 10.17 and 10.70 kilometers in diameter, and its surface has an
albedo
Albedo ( ; ) is the fraction of sunlight that is Diffuse reflection, diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects ...
between of 0.244 and 0.21, respectively (without preliminary results).
The ''Collaborative Asteroid Lightcurve Link'' assumes an albedo of 0.21 – derived from
15 Eunomia
15 Eunomia is a very large asteroid in the middle asteroid belt. It is the largest of the stony ( S-type) asteroids, with 3 Juno as a close second. It is quite a massive asteroid, in 6th to 8th place (to within measurement uncertainties). It is ...
, the family's largest member and namesake – and calculates a diameter of 11.03 kilometers using an
absolute magnitude of 12.1.
Naming
This
minor planet
According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor ...
was named for the small village of
Zimmerwald
Zimmerwald () was an independent municipality in the Canton of Bern, Switzerland until 31 December 2003. It is located on a hill in the proximity of the city of Bern in the Bernese Mittelland. On 1 January 2004 Zimmerwald united with the municipa ...
, location of the discovering Zimmerwald Observatory. It is located about seven miles south of the Swiss capital
Bern
Bern (), or Berne (), ; ; ; . is the ''de facto'' Capital city, capital of Switzerland, referred to as the "federal city".; ; ; . According to the Swiss constitution, the Swiss Confederation intentionally has no "capital", but Bern has gov ...
, after which the binary asteroid
1313 Berna was named.
The official was published by the
Minor Planet Center
The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory.
Funct ...
on 18 April 1977 ().
References
External links
Asteroid Lightcurve Database (LCDB) query form
)
Dictionary of Minor Planet Names Google books
– Observatoire de Genève, Raoul Behrend
– Minor Planet Center
*
*
{{DEFAULTSORT:Zimmerwald
001775
Discoveries by Paul Wild (Swiss astronomer)
Named minor planets
001775
001775
19690513