1078 Mentha, provisional designation , is a stony background

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 ...

from the inner regions 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 13 kilometers in diameter. It was discovered on 7 December 1926, by astronomer

Karl Reinmuth Karl Wilhelm Reinmuth (4 April 1892 in Heidelberg – 6 May 1979 in Heidelberg) was a German astronomer and a prolific discoverer of 395 minor planets. Scientific career From 1912 to 1957, Reinmuth was working as an astronomer at the He ...

at the

Heidelberg-Königstuhl State Observatory Heidelberg-Königstuhl State Observatory () is a historic astronomical observatory located near the summit of the Königstuhl hill in the city of Heidelberg in Germany. It is operated by the ''Center for Astronomy (ZAH)'' at the University of He ...

in southwest Germany. Only in 1958, it was realized that this object was a rediscovery of an already numbered but

lost asteroid Lost or LOST may refer to getting lost, or to: Arts, entertainment, and media Television * ''Lost'' (TV series), a 2004 American drama series about people who become stranded on a mysterious island * ''Lost'' (2001 TV series), a short-lived Ameri ...

( 864 Aase). The asteroid was named after the flowering plant of the mint family, ''

Mentha ''Mentha'', also known as mint (from Greek , Linear B ''mi-ta''), is a genus of flowering plants in the mint family, Lamiaceae. It is estimated that 13 to 24 species exist, but the exact distinction between species is unclear. Hybridization oc ...

''. It has a longer-than average spin rate of 85 hours and possibly an irregular, elongated shape.

Identification with former lost asteroid

Sometimes, discovered objects turn out to be a rediscovery of a previously

lost minor planet Lost or LOST may refer to getting lost, or to: Arts, entertainment, and media Television * ''Lost'' (TV series), a 2004 American drama series about people who become stranded on a mysterious island * ''Lost'' (2001 TV series), a short-lived Ameri ...

. This can be determined by calculating the "new" object's orbit (once it is firmly known) backwards and checking its past positions against those previously recorded for the lost object. Nowadays these identities between two objects are found before they are numbered. In 1958, however, French astronomer André Patry at

Nice Observatory The Nice Observatory () is an astronomical observatory located in Nice, France on the summit of Mount Gros. The observatory was founded in 1879, by the banker Raphaël Bischoffsheim. The architect was Charles Garnier (architect), Charles Garnier, ...

found such identity between ''Mentha'', , and the lost minor planet 864 Aase, , which had never been re-observed after its discovery by

Max Wolf Maximilian Franz Joseph Cornelius Wolf (21 June 1863 – 3 October 1932) was a German astronomer and a pioneer in the field of astrophotography. He was the chairman of astronomy at the University of Heidelberg and director of the Heidelberg-K� ...

in 1917. Since it was realized that ''Mentha'' and ''Aase'' were one and the same object, 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 ...

resolved this conflict by keeping everything associated with "1078 Mentha", adding the two oppositional observations by Max Wolf from 1917, and completely vacated "864 Aase", reusing its name and number for another, unrelated discovery made by Reinmuth.

Orbit and classification

''Mentha'' is a non-

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

asteroid of the main belt's background population. It orbits the Sun in the inner asteroid belt at a distance of 2.0–2.6 AU once every 3 years and 5 months (1,249 days;

semi-major axis In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the longe ...

of 2.27 AU). 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 0.14 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 7 ° 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 asteroid was first observed as at Heidelberg in February 1907 (which is the original discovery of , before vacated). 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 ...

begins at

Simeiz Observatory Simeiz Observatory (also spelled Simeis or Simeïs) was an astronomy research observatory until the mid-1950s. It is located on Mount Koshka, Crimea, by the town of Simeiz. Part of the Crimean Astrophysical Observatory, it is currently used fo ...

in March 1924, almost four years prior to its official discovery observation at Heidelberg.

Physical characteristics

In the

Tholen classification An asteroid spectral type is assigned to asteroids based on their reflectance spectrum, color, and sometimes albedo. These types are thought to correspond to an asteroid's surface composition. For small bodies that are not internally different ...

, ''Mentha'' is a common 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 ...

Rotation period

In February 1989, a first 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 ''Mentha'' was obtained from photometric observations by Polish astronomer Wiesław Wiśniewski. Lightcurve analysis gave a well-defined

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 85 hours with a brightness variation of 0.87

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 ...

(). In February 2013, a similar period of 82.870 hours with an amplitude of 0.65 magnitude was measured by astronomers at the

Palomar Transient Factory The Palomar Transient Factory (PTF, obs. code: I41), was an astronomical survey using a wide-field survey camera designed to search for optical transient and variable sources such as variable stars, supernovae, asteroids and comets. The projec ...

in California (). A high brightness amplitude is typically indicative for an elongated rather than spherical shape. Its long period is close to that of slow rotators.

Diameter and albedo

According to the surveys carried out by the Japanese Akari satellite and the

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 of 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 ...

, ''Mentha'' measures between 9.94 and 15.37 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 0.126 and 0.343. The ''Collaborative Asteroid Lightcurve Link'' agrees with

Petr Pravec Petr Pravec (born September 17, 1967) is a Czech astronomer and a discoverer of minor planets, born in Třinec, Czech Republic. Pravec is a prolific discoverer of binary asteroids, expert in photometric observations and rotational lightcurves ...

's revised WISE data and takes an albedo of 0.1641 and a diameter of 13.68 kilometers based on an absolute magnitude of 11.9.

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 after ''

'', a flowering herb of the

mint family The Lamiaceae ( ) or Labiatae are a family of flowering plants commonly known as the mint, deadnettle, or sage family. Many of the plants are aromatic in all parts and include widely used culinary herbs like basil, mint, rosemary, sage, sav ...

. The official naming citation was mentioned in ''

The Names of the Minor Planets Paul Herget (January 30, 1908 – August 27, 1981) was an American astronomer and director of the Cincinnati Observatory, who established the Minor Planet Center after World War II. Career Herget taught astronomy at the University of Cincinna ...

'' by

Paul Herget Paul Herget (January 30, 1908 – August 27, 1981) was an American astronomer and director of the Cincinnati Observatory, who established the Minor Planet Center after World War II. Career Herget taught astronomy at the University of Cincinna ...

in 1955 ().

Reinmuth's flowers

Due to his many discoveries,

submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between and . This list also contained a sequence of 28 asteroids, starting with 1054 Forsytia, that were all named after plants, in particular

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s ''(also see list of minor planets named after animals and plants)''.

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:Mentha 001078 Discoveries by Karl Wilhelm Reinmuth Named minor planets 001078 19261207