• Source: 4001 Ptolemaeus

4001 Ptolemaeus, provisional designation 1949 PV, is a Florian asteroid from the inner regions of the asteroid belt, approximately 5 kilometers (3.1 miles) in diameter. It was discovered on 2 August 1949, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in Heidelberg, Germany. In 1991, the International Astronomical Union named the S-type asteroid after Greco-Roman astronomer Ptolemy.




Orbit and classification


Ptolemaeus is a member of the Flora family (402), a giant asteroid family and the largest family of stony asteroids in the main-belt. It orbits the Sun in the inner main-belt at a distance of 1.9–2.7 AU once every 3 years and 6 months (1,264 days; semi-major axis of 2.29 AU). Its orbit has an eccentricity of 0.17 and an inclination of 5° with respect to the ecliptic.
The body's observation arc begins with its observations as 1949 QD1 at Lowell Observatory on 24 August 1949, or three weeks after its official discovery observation at Heidelberg. On 24 April 1989, Ptolemaeus approached the asteroid 6 Hebe within 5.5 million kilometers at a relative velocity of 3.7 km/s.




Physical characteristics


In the SMASS classification, Ptolemaeus is a common, stony S-type asteroid, which is in agreement with the overall spectral type for members of the Flora family.: 23 




= Diameter and albedo

=
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Ptolemaeus measures 4.641 kilometers in diameter and its surface has a high albedo of 0.392. Based on a generic magnitude-to-diameter conversion, assuming a Flora-type typical albedo of 0.24, the asteroid measures 5.0 kilometers for an absolute magnitude of 13.7.




= Rotation period

=
As of 2018, no rotational lightcurve of Ptolemaeus has been obtained from photometric observations. Its rotation period, poles and shape remain unknown.




Naming


This minor planet was named after 2nd-century Greco-Roman astronomer Ptolemy (Latin: "Ptolemaeus") by IAU's Minor Planet Names Committee. He is best known for his influential Almagest, a mathematical and astronomical treatise on the apparent motions of the stars and planetary paths. Its ideas dominated astronomy for 1200 years until Copernicus in the early Renaissance. The official naming citation was published by the Minor Planet Center on 21 November 1991 (M.P.C. 19335).




References






External links


Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
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
4001 Ptolemaeus at AstDyS-2, Asteroids—Dynamic Site
Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
4001 Ptolemaeus at the JPL Small-Body Database

Kata Kunci Pencarian:

• 4001 Ptolemaeus
• Ptolemy (disambiguation)
• Ptolemaeus (lunar crater)
• Meanings of minor-planet names: 4001–5000
• Ptolemy
• List of minor planets: 4001–5000
• Karl Wilhelm Reinmuth
• List of minor planets named after people
• List of named minor planets: P
• List of named minor planets: 4000–4999