astro.wikisort.org - Asteroid

(219774) 2001 YY₁₄₅, provisional designation 2001 YY₁₄₅ is a stony background asteroid and exceptionally slow rotator from the central region of the asteroid belt, approximately 1.5 kilometers (0.9 miles) in diameter. It was discovered on 18 December 2001, by astronomers with the Lowell Observatory Near-Earth-Object Search at Anderson Mesa Station near Flagstaff, Arizona, in the United States.[1] The assumed S-type asteroid is likely elongated and has a rarely seen rotation period of 1007 hours, making it the 13th slowest rotator.[5]

(219774) 2001 YY₁₄₅

Discovery[1]
Discovered by	LONEOS
Discovery site	Anderson Mesa Stn.
Discovery date	18 December 2001
Designations
MPC designation	(219774) 2001 YY145
Alternative designations	2001 YY145 · 2005 TA170
Minor planet category	main-belt[1][2] · (middle) background[3][4]
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	15.92 yr (5,815 d)
Aphelion	2.9215 AU
Perihelion	2.2404 AU
Semi-major axis	2.5810 AU
Eccentricity	0.1320
Orbital period (sidereal)	4.15 yr (1,515 d)
Mean anomaly	48.043°
Mean motion	0° 14m 15.72s / day
Inclination	9.6001°
Longitude of ascending node	315.61°
Argument of perihelion	18.718°
Physical characteristics
Mean diameter	1.54 km (calculated)[5]
Synodic rotation period	1007.6706±86.3718 h[4][6]
Geometric albedo	0.20 (assumed)[5]
Spectral type	S (assumed)[5]
Absolute magnitude (H)	15.9[1][2] 15.977±0.011 (R)[6] 16.43[5]

Orbit and classification

2001 YY₁₄₅ is a non-family asteroid from the main belt's background population.[3][4] It orbits the Sun in the central main-belt at a distance of 2.2–2.9 AU once every 4 years and 2 months (1,515 days; semi-major axis of 2.58 AU). Its orbit has an eccentricity of 0.13 and an inclination of 10° with respect to the ecliptic.[2] A first precovery was taken at Lincoln Lab's ETS in October 2001, extending the asteroid's observation arc by 2 months prior to its official discovery observation at Anderson Mesa.[1]

Physical characteristics

The object is an assumed, common S-type asteroid.[5]

Slow rotator

In October 2013, a rotational lightcurve was obtained of this asteroid from photometric observations in the R-band by astronomers at the Palomar Transient Factory in California. It gave a rotation period of 1007.7 hours – or nearly 42 days – with an assigned error margin of ±86 hours. According to the Light Curve Data Base, it is the 13th slowest rotating minor planet known to exist among more than 15,000 observed small Solar System bodies. Due to its high brightness variation of 0.86 magnitude, the body is likely to have a non-spheroidal shape (U=2).[6] As of 2018, no follow-up observation have been published.[5]

Diameter and albedo

The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 1.54 kilometers, based on an absolute magnitude of 16.43.[5]

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 4 October 2009.[7] As of 2018, it has not been named.[1]

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
• Discovery Circumstances: Numbered Minor Planets (215001)-(220000) – Minor Planet Center
• (219774) 2001 YY145 at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• (219774) 2001 YY145 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

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