astro.wikisort.org - Asteroid

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.[1]

4001 Ptolemaeus

Orbit of 4001 Ptolemaeus
Discovery [1]
Discovered by	K. Reinmuth
Discovery site	Heidelberg Obs.
Discovery date	2 August 1949
Designations
MPC designation	(4001) Ptolemaeus
Pronunciation	/tɒləˈmiːəs/
Named after	Ptolemy [1] (Greco-Roman astronomer)
Alternative designations	1949 PV · 1949 QD1 1982 BU9 · 1987 OE
Minor planet category	main-belt [1][2] · (inner) Flora [3]
Orbital characteristics [2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	67.75 yr (24,744 d)
Aphelion	2.6809 AU
Perihelion	1.8940 AU
Semi-major axis	2.2874 AU
Eccentricity	0.1720
Orbital period (sidereal)	3.46 yr (1,264 d)
Mean anomaly	294.51°
Mean motion	0° 17m 5.64s / day
Inclination	5.4568°
Longitude of ascending node	130.67°
Argument of perihelion	204.09°
Physical characteristics
Mean diameter	4.641±0.297 km[4] 5.0 km (est. at 0.24)[5]
Geometric albedo	0.392±0.056[4]
Spectral type	SMASS = S [2]
Absolute magnitude (H)	13.7[2]

Orbit and classification

Ptolemaeus is a member of the Flora family (402),[3] a giant asteroid family and the largest family of stony asteroids in the main-belt.[6] 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.[2]

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.[1] On 24 April 1989, Ptolemaeus approached the asteroid 6 Hebe within 5.5 million kilometers at a relative velocity of 3.7 km/s.[2]

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.[6]^: 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.[4] 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.[5]

Rotation period

As of 2018, no rotational lightcurve of Ptolemaeus has been obtained from photometric observations. The body's rotation period, poles and shape remain unknown.[2]

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.[1] The official naming citation was published by the Minor Planet Center on 21 November 1991 (M.P.C. 19335).[7]

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
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

На других языках

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[de] (4001) Ptolemaeus

(4001) Ptolemaeus ist ein Hauptgürtelasteroid der am 2. August 1949 vom deutschen Astronomen Karl Wilhelm Reinmuth von der Landessternwarte Heidelberg-Königstuhl (Sternwarten-Code 024) aus entdeckt wurde.

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- [en] 4001 Ptolemaeus

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[ru] (4001) Птолемей

(4001) Птолемей (лат. Ptolemaeus, др.-греч. Πτολεμαῖος) — астероид главного пояса, который принадлежит к светлому спектральному классу S. Он был открыт 2 августа 1949 года немецким астрономом Карлом Рейнмутом в обсерватории Хайдельберг в Германии и названный в честь древнегреческого учёного Клавдия Птолемея[1].

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