173 Ino is a large

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 the parent body of the Ino family, located in the central 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 in diameter. It was discovered on 1 August 1877, by French astronomer Alphonse Borrelly at Marseille Observatory in southern France, and named after the queen Ino from

Greek mythology Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of ancient Greek folklore, today absorbed alongside Roman mythology into the broader designation of classical mythology. These stories conc ...

. The dark Xk-type asteroid has a

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 6.15 hours.

Orbit and classification

''Ino'' is the parent body and namesake of the Ino family (), an asteroid family in the intermediate main belt with nearly 500 known members. The adjectival form of the asteroid name is "Inoan". It orbits the Sun in the central main-belt at a distance of 2.2–3.3 AU once every 4 years and 6 months (1,659 days; semi-major axis of 2.74 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 0.21 and an inclination of 14 ° 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 body's observation arc begins at Düsseldorf-Bilk Observatory in January 1879, five months after its official discovery observation at Marseilles.

Physical characteristics

In the Tholen classification, ''Ino'' is a common carbonaceous C-type, while in the SMASS classification it is a Xk-subtype that transitions between the X-type and uncommon K-type asteroids. Multiple photometric studies of this asteroid were performed between 1978 and 2002. The combined data gave an irregular, asymmetrical

light curve 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 ...

with a period of 6.163 ± 0.005 hours and a brightness variation of 0.10–0.15 in magnitude. The asteroid is rotating in a retrograde direction.

Notes

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:000173 18770801 Ino Ino asteroids Ino C-type asteroids (Tholen) Xk-type asteroids (SMASS)