(84719) 2002 VR ₁₂₈

Asteroid (84719) 2002 VR 128
Properties of the orbit ( animation ) Epoch:  April 27, 2019 ( JD 2,458,600.5)
Orbit type	Plutino , "Distant Object"
Major semi-axis	39.297  AU
eccentricity	0.266
Perihelion - aphelion	28.826 AU - 49.769 AU
Inclination of the orbit plane	14 °
Length of the ascending node	23.1 °
Argument of the periapsis	287.5 °
Time of passage of the perihelion	October 23, 1965
Sidereal period	246 a 4.2 M
Mean orbital velocity	4.712 km / s
Physical Properties
Medium diameter	${\displaystyle 448{,}5_{-43,2}^{+42,1}\,\mathrm {km} }$
Albedo	${\displaystyle 0{,}052_{-0,018}^{+0,027}\mathrm {} }$
Absolute brightness	5.58 ± 0.37 mag
Spectral class	C B − V = 0.940 ± 0.030 V − R = 0.600 ± 0.020
history
Explorer	Chadwick A. Trujillo Michael E. Brown Eleanor F. Helin Steven H. Pravdo Kenneth J. Lawrence Michael Hicks
Date of discovery	November 3, 2002
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.

(84719) 2002 VR ₁₂₈ is a large trans-Neptunian object in the Kuiper belt , which is classified as Plutino in terms of orbital dynamics . Because of its size, the asteroid is a dwarf planet candidate .

discovery

2002 VR ₁₂₈ was discovered on November 3, 2002 by Chad Trujillo and Mike Brown (official) as well as Eleanor "Glo" Helin , Steven Pravdo, Kenneth Lawrence and Michael Hicks as part of the Near Earth Asteroid Tracking Project (NEAT) with the 1.2 m Oschin Schmidt telescope discovered at Palomar Observatory ( California ). The discovery was announced on November 21, 2002 together with the 2002 MS ₄ and 2002 QX ₄₇ , the planetoid was given the minor planet number 84719 by the IAU .

After its discovery, VR _{128 could be identified} in photos up to October 1, 1983, taken as part of the Digitized Sky Survey program at the Siding Spring Observatory ( Australia ), and so its observation period was extended by 19 years in order to calculate its orbit more precisely. In April 2017, there were a total of 128 observations over a period of 32 years. The last observation so far was made in December 2017 at the Lowell Observatory . (As of March 3, 2019)

properties

Orbit

2002 VR ₁₂₈ orbits the sun in 246.35 years on a slightly elliptical orbit between 28.83  AU and 49.77 AU from its center. The orbit eccentricity is 0.266, the orbit is inclined 14.03 ° to the ecliptic . Currently, the planetoid is 39.88 AU from the sun. He last passed through perihelion in 1965, so the next perihelion is likely to take place in 2212.

Similar to Pluto and Huya , in 2002 VR ₁₂₈ belongs to the group of asteroids that cross the orbit of Neptune , ie come closer to the sun than it, even if they are controlled by Neptune due to the 2: 3 orbit resonance . 2002 VR ₁₂₈ is according to the current state of knowledge after Pluto and before Huya the second largest Plutino of this type.

Both Marc Buie ( DES ) and the Minor Planet Center classify the planetoid as Plutino ; the latter also lists it as a non-SDO and generally as a “distant object” .

size

A diameter of 448.5 km is currently assumed, based on a reflectivity of 5.2% and an absolute brightness of 5.58  ^m . Assuming a diameter of 448.5 km, this results in a total surface of about 632,000 km². The apparent brightness of 2002 VR ₁₂₈ is 21.51  ^m , the mean surface temperature is estimated at 44 K (−229 ° C) based on the distance from the sun  .

Since it can be assumed that 2002 VR ₁₂₈ is in hydrostatic equilibrium due to its size and must therefore be largely round, it should meet the criteria for classification as a dwarf planet . Mike Brown believes that it is in 2002 VR ₁₂₈ to possibly is a dwarf planet.

Using light curve observations , the surface appears reddish in visible light.

Provisions of the diameter for 2002 VR ₁₂₈

year	Dimensions km	source
2012	448.5 + 042.1- 043.2	Mommert et al. a.
2018	459.0	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} Marc W. Buie : Orbit Fit and Astrometric record for 84719 . SwRI (Space Science Department). Retrieved March 3, 2019.
2. ↑ ^{a b} MPC : MPEC 2010-S44: Distant Minor Planets (2010 OCT.11.0 TT) . IAU . September 25, 2010. Retrieved March 3, 2019.
3. ^ Wm. R. Johnston: List of Known Trans-Neptunian Objects . Johnston's Archives. October 7, 2018. Retrieved March 3, 2019.
4. ↑ ^{a b c d} (84719) 2002 VR128 at the IAU Minor Planet Center (English) Retrieved March 3, 2019.
5. ↑ v ≈ π * a / period (1 + sqrt (1-e²))
6. ↑ ^{a b c d e f g} M. Mommert u. a .: “TNOs are Cool”: A survey of the trans-Neptunian region. V. Physical characterization of 18 Plutinos using Herschel-PACS observations . In: Astronomy and Astrophysics . 541, no.A93 , February 16, 2012. arxiv : 1202.3657 . bibcode : 2012A & A ... 541A..93M . doi : 10.1051 / 0004-6361 / 201118562 .
7. ↑ ^{a b} (84719) 2002 VR128 in the Small-Body Database of the Jet Propulsion Laboratory (English). Retrieved March 3, 2019.
8. ↑ MPC : MPEC 2002-W27: 2002 MS4, 2002 QX47, 2002 VR128 . IAU . November 21, 2002. Retrieved March 3, 2019.
9. ↑ MPC : MPEC List Of Centaurs and Scattered-Disk Objects . IAU . Retrieved March 3, 2019.
10. ↑ (84719) 2002 VR128 in the database of the "Asteroids - Dynamic Site" (AstDyS-2, English).
11. ↑ ^{a b} Mike Brown : How many dwarf planets are there in the outer solar system? . CalTech . November 12, 2018. Retrieved March 3, 2019.