Astronomy:(495603) 2015 AM281

(495603) 2015 AM₂₈₁

Discovery
Discovered by	Pan-STARRS 1
Discovery site	Haleakala Obs.
Discovery date	13 March 2010
Designations
MPC designation	(495603) 2015 AM281
Alternative designations	2015 AM281
Minor planet category	TNO · res 2:5 distant
Orbital characteristics
Epoch 27 April 2019 (JD 2458600.5)
Uncertainty parameter 3
Observation arc	23.14 yr (6,261 d)
Earliest precovery date	6 April 2000
|{{{apsis}}}|helion}}	68.916 AU
|{{{apsis}}}|helion}}	41.357 AU
Semi-major axis	55.137 AU
Eccentricity	0.2499
Orbital period	409.42 yr (149,540 d)
Mean anomaly	335.33°
Mean motion	0° 0m 8.64s / day
Inclination	26.719°
Longitude of ascending node	22.124°
|{{{apsis}}}|helion}}	158.18°
Physical characteristics
Mean diameter	468 km (est.) 479 km (est.)
Geometric albedo	0.07 (assumed) 0.09 (assumed)
Absolute magnitude (H)	4.8 4.86

(495603) 2015 AM₂₈₁ (provisional designation 2015 AM₂₈₁) is a resonant trans-Neptunian object in the outermost region of the Solar System, guesstimated at approximately 470 kilometers (290 miles) in diameter. It was discovered on 13 March 2010, by astronomers with the Pan-STARRS survey at Haleakala Observatory, Hawaii, United States.

Discovery

The body's observation arc begins with a precovery taken by the Sloan Digital Sky Survey in April 2000, nearly 10 years prior to its official discovery observation at Haleakala Observatory. The discovery was announced in a Minor Planet Electronic Circular in July 2016, after additional observations by Pan-STARRS had been found (2010–2013), preceding the team's original observation from 11 January 2015, which led to the assignment of the object's first and only provisional designation, 2015 AM₂₈₁. The observations were made with Pan-STARRS 1.8-meter Ritchey–Chrétien telescope, and B. Gibson, T. Goggia, N. Primak, A. Schultz, and M. Willman were the observers.

Orbit and classification

2015 AM₂₈₁ is a resonant trans-Neptunian object in a 2:5 orbital resonance with Neptune, which means that it orbits the Sun exactly twice while Neptune orbits the Sun five times. Several objects in this resonance with a period of 410 years have been found, including 2002 TC₃₀₂.

It orbits the Sun at a distance of 41.4–68.9 AU once every 409 years and 5 months (149,540 days; semi-major axis of 55.14 AU). Its orbit has an eccentricity of 0.25 and an inclination of 27° with respect to the ecliptic. It still has an orbital uncertainty of 1 and 3, respectively.

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 9 June 2017 and received the number 495603 in the minor planet catalog (M.P.C. 105261). As of 2018, it has not been named.

Physical characteristics

According to the Johnston's archive and American astronomer Michael Brown, 2015 AM₂₈₁ measures 468 and 479 kilometers in diameter based on an assumed albedo of 0.09 and 0.07, respectively. As of 2018, no rotational lightcurve has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.

External links

• MPEC 2016-O294: 2015 AM281, Minor Planet Electronic Circular, 24 July 2016
• M.P.E.C. statistics for F51 – All MPECs
• Image of 2015 AM281, at San Marcello, May 2017 (blogpost)
• List of Known Trans-Neptunian Objects, Johnston's Archive
• The largest asteroids and outer solar system objects, Johnston's Archive, 2018
• List Of Centaurs and Scattered-Disk Objects, Minor Planet Center
• Discovery Circumstances: Numbered Minor Planets (495001)-(500000) – Minor Planet Center
• (495603) 2015 AM281, Small Bodies Data Ferret
• (495603) 2015 AM281 at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• (495603) 2015 AM281 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters