679 Pax is a

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 ...

orbiting the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

that was discovered by German astronomer

August Kopff August Kopff (February 5, 1882 – April 25, 1960) was a German astronomer and discoverer of several comets and asteroids. Kopff studied and worked in Heidelberg, getting his PhD there in 1906 and he then joined the Humboldt University of Berli ...

on January 28, 1909. It is named after

Pax Pax or PAX may refer to: Peace * Peace (Latin: ''pax'') ** Pax (goddess), the Roman goddess of peace ** Pax, a truce term * Pax (liturgy), a salutation in Catholic and Lutheran religious services * Pax (liturgical object), an object formerly ki ...

, a Roman goddess. It is orbiting the

with a

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

of 4.16 years and 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 0.31. Measurements using the

adaptive optics Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of incoming wavefront distortions by deforming a mirror in order to compensate for the distortion. It is used in astronomical tele ...

at the

W. M. Keck Observatory The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have aperture primary mirrors, and when comp ...

give a mean diameter of 62 km. This is 16% larger than the diameter estimated using the

IRAS The Infrared Astronomical Satellite (Dutch: ''Infrarood Astronomische Satelliet'') (IRAS) was the first space telescope to perform a survey of the entire night sky at infrared wavelengths. Launched on 25 January 1983, its mission lasted ten mo ...

observatory. The asteroid is elongated with a size ratio of 1.66 ± 0.23 between the major and minor axes. Photometric measurements reported in 1982 gave a rotation period of 8.452 hours. The asteroid's

pole Pole may refer to: Astronomy *Celestial pole, the projection of the planet Earth's axis of rotation onto the celestial sphere; also applies to the axis of rotation of other planets *Pole star, a visible star that is approximately aligned with the ...

of rotation lies 32° away from the

plane of the ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic agains ...

Polarimetric Polarimetry is the measurement and interpretation of the polarization of transverse waves, most notably electromagnetic waves, such as radio or light waves. Typically polarimetry is done on electromagnetic waves that have traveled through or ...

study of this asteroid reveals anomalous properties that suggests the

regolith Regolith () is a blanket of unconsolidated, loose, heterogeneous superficial deposits covering solid rock. It includes dust, broken rocks, and other related materials and is present on Earth, the Moon, Mars, some asteroids, and other terrestria ...

consists of a mixture of low and high

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

material. This may have been caused by fragmentation of an asteroid substrate with the spectral properties of CO3/CV3

carbonaceous chondrites Carbonaceous chondrites or C chondrites are a class of chondritic meteorites comprising at least 8 known groups and many ungrouped meteorites. They include some of the most primitive known meteorites. The C chondrites represent only a small prop ...

References

External links

* * Background asteroids

I-type asteroids (Tholen) K-type asteroids (SMASS) 19090128 {{beltasteroid-stub

References

See also

External links