173 Ino

173 Ino is a large asteroid and the parent body of the Ino family, located in the central regions of the asteroid belt, approximately Template:Convert 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. The dark Xk-type asteroid has a rotation period of 6.15 hours.

Orbit and classification

Ino is the parent body and namesake of the Ino family (Template:Small), an asteroid family in the intermediate main belt with nearly 500 known members.Template:Rp 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 of 0.21 and an inclination of 14° with respect to the ecliptic. 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 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.

External links

• Asteroid Lightcurve Database (LCDB), query form (info Template:Webarchive)
• Dictionary of Minor Planet Names, Google books
• Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
• Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
• Template:AstDys
• Template:JPL small body