2012 BW ₁₅₄

Asteroid 2012 BW 154
Properties of the orbit ( animation ) Epoch:  April 27, 2019 ( JD 2,458,600.5)
Orbit type	"Other TNO" , "Distant Object"
Major semi-axis	45.838  AU
eccentricity	0.142
Perihelion - aphelion	39.332 AU - 52.345 AU
Inclination of the orbit plane	7.9 °
Length of the ascending node	66.1 °
Argument of the periapsis	56.4 °
Time of passage of the perihelion	August 25, 1993
Sidereal period	310 a 4.2 M
Mean orbital velocity	4.363 km / s
Physical Properties
Medium diameter	approx. 315 km
Albedo	0.08-0.09
Absolute brightness	5.6 - 5.9 mag
history
Explorer	Pan-STARRS : B. Gibson T. Goggia N. Primak A. Schultz M. Willman
Date of discovery	January 20, 2012
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items.

2012 BW ₁₅₄ is a large trans-Neptunian object in the Kuiper Belt , whose orbit classification is unclear. Due to its size, the asteroid is one of the dwarf planet candidates .

discovery

2012 BW ₁₅₄ was tested on January 20, 2012 by a team of astronomers consisting of B. Gibson, T. Goggia, N. Primak, A. Schultz and M. Willman, as part of the Pan-STARRS project with the 1.8 m -Ritchey Chretien Telescope (PS1) discovered at Haleakalā Observatory ( Maui ). The discovery was announced on July 26, 2016.

After its discovery, BW _{154 could be identified} on photos taken as part of the Sloan Digital Sky Survey program (SDSS) at the Apache Point Observatory ( New Mexico ) in 2012 going back to December 20, 2004, thus changing its observation period eight years to more accurately calculate its orbit. So far, the planetoid has only been observed by the Pan-STARRS and the Apache Point observatory. In March 2019, a total of 153 observations were made over a period of 15 years. The last observation so far was carried out again at the Pan-STARRS telescope in January 2019. (As of March 27, 2019)

properties

Orbit

2012 BW ₁₅₄ orbits the sun in 310.35 years on a slightly elliptical orbit between 39.33  AU and 52.35 AU from its center. The orbit eccentricity is 0.142, the orbit is 7.86 ° inclined to the ecliptic . The planetoid is currently 40.46 AU from the sun. The last time he went through perihelion was in 1993, the next perihelion should therefore take place in 2304.

Neither Marc Buie ( DES ) nor the Minor Planet Center has a specific classification; the latter only lists it as a non-SDO and generally as a “distant object” . The Johnston's Archive lists it as "other TNO" , which means it is definitely not a Cubewano or Resonantes KBO .

size

A diameter of 315 km is currently assumed, based on a reflectivity of 8% and an absolute brightness of 5.9  ^m . Based on this diameter, the total area is about 312,000 km². The apparent magnitude of 2012 BW ₁₅₄ is 21.54  ^m .

Since it is conceivable that 2012 BW ₁₅₄ is in hydrostatic equilibrium due to its size and could therefore be largely round, it may meet the criteria for classification as a dwarf planet . Mike Brown expects that it is at 2012 BW ₁₅₄ to perhaps is a dwarf planet.

Determinations of the diameter for 2012 BW ₁₅₄

year	Dimensions km	source
2018	336.0	Johnston
2018	315.0	Brown
The most precise determination is marked in bold .

See also

• List of trans-Neptunian objects
• List of dwarf planets of the solar system
• List of asteroids
• List of moons from asteroids

Web links

• How many dwarf planets are there in the outer solar system? Current list of the largest TNOs from Mike Brown
• Free the dwarf planets! Mike Brown's column on the IAU and the dwarf planets regarding their classifications (23 August 2011)

Individual evidence

1. ↑ ^{a b c} Wm. R. Johnston: List of Known Trans-Neptunian Objects . Johnston's Archives. October 7, 2018. Retrieved March 27, 2019.
2. ↑ ^{a b c} 2012 BW154 at the IAU Minor Planet Center (English). Accessed March 27, 2019.
3. ↑ v ≈ π * a / period (1 + sqrt (1-e²))
4. ↑ MPC : MPEC 2016-O349: 2012 BW154 . IAU . July 26, 2016. Retrieved March 27, 2019.
5. ↑ 2012 BW154 in the Small-Body Database of the Jet Propulsion Laboratory (English). Retrieved March 27, 2019.
6. ^ Marc W. Buie : Orbit Fit and Astrometric record for 12BW154 . SwRI (Space Science Department). Retrieved March 27, 2019.
7. ↑ MPC : MPEC List Of Centaurs and Scattered-Disk Objects . IAU . Retrieved March 27, 2019.
8. ↑ 2012 BW154 in the database of the "Asteroids - Dynamic Site" (AstDyS-2, English).
9. ↑ ^{a b} Mike Brown : How many dwarf planets are there in the outer solar system? . CalTech . November 12, 2018. Retrieved March 27, 2019.