List of possible dwarf planets

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Illustration of the relative sizes, albedos, and colours of the largest trans-Neptunian objects

It is estimated that there may be 200 dwarf planets in the Kuiper belt of the outer Solar System and up to 10,000 in the region beyond.[1][2] The International Astronomical Union (IAU) has accepted four of these: Pluto, Eris, Haumea, and Makemake, as well as Ceres in the inner Solar System. This article lists these and the more likely of the remaining known possibilities.

IAU naming procedures[edit]

In 2008, the IAU modified its naming procedures such that objects considered most likely to be dwarf planets receive differing treatment than others. Objects that have an absolute magnitude (H) less than +1 (and hence a mathematically delimited minimum diameter of 838 kilometres (521 mi)[3]) are overseen by two naming committees, one for minor planets and one for planets. Once named, the objects are declared to be dwarf planets. Makemake and Haumea are the only objects to have proceeded through the naming process as presumed dwarf planets; currently there are no other bodies which meet this requirement. All other bodies are named by the minor-planet naming committee alone, and the IAU has not stated how or if they will be accepted as dwarf planets.

Limiting values[edit]

Colours of trans-Neptunians. Mars and Triton are not to scale. Phoebe and Pholus are not TNOs.

The qualifying feature of a dwarf planet is that it "has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape".[4][5][6] Except for Pluto and Ceres, current observations are insufficient for a direct determination if a body meets this definition. However, Michael Brown estimates that an icy body relaxes into hydrostatic equilibrium at a diameter somewhere between 200 and 400 km.[1] Thus, all the trans-Neptunian objects (TNOs) listed below are estimated to be at least 400 kilometres (250 mi) in diameter, though not all bodies estimated to be that size are included. The lists are further complicated by bodies such as (47171) 1999 TC36 that were at first assumed to be large single objects but were later discovered to be smaller binary or triple systems.[7]

Ceres is the only identified dwarf planet in the asteroid belt. The most likely other possibility is 4 Vesta, the second-most-massive asteroid; Vesta appears to have a fully differentiated interior and was therefore in equilibrium at some point in its history, though it apparently is not today.[8] The third-most massive object, 2 Pallas, has a somewhat irregular surface and is thought to have only a partially differentiated interior. Brown estimates that, since rocky objects are more rigid than icy objects, rocky objects below 900 kilometres (560 mi) in diameter may not be in hydrostatic equilibrium and thus not dwarf planets.[1]

List by absolute magnitude (H)[edit]

Because size estimates are often crude and vary widely, it is less arbitrary to list objects by absolute magnitudes than by diameter. Theoretical minimum diameters correspond to a maximum albedo of 1. Eris has a high albedo of 0.8–0.9. Members of the Haumea family are also thought to be bright and thus close to the theoretical minimum. However, many objects are thought to be dark due to tholins causing a red-sloped reflectance spectrum, and, therefore, red objects may be substantially larger than the lower limit.

As of December 2013, there are 168 trans-Neptunian objects, one centaur and 13 asteroids with an absolute magnitude (H) brighter than 6.[9]

The lists below only show the bodies with magnitudes of H<5 (63 trans-Neptunian objects and 3 asteroids) as for H=5 the minimum diameter is only a third of the 400 kilometres (250 mi) limit. For bodies with absolute magnitudes dimmer than H=6, even a dark albedo of 0.04 corresponds to a diameter less than 400 km.[3]

Brighter than 1[edit]

Earth Dysnomia Eris Charon Nix Hydra S/2011 (134340) 1 Pluto Makemake Namaka Hi'iaka Haumea Sedna 2007 OR10 Weywot Quaoar Vanth Orcus File:EightTNOs.png
Artistic comparison of Eris, Pluto, Makemake, Haumea, Sedna, 2007 OR10, Quaoar, Orcus, and Earth. ( )

These have all been accepted as dwarf planets by the IAU.

Name H[10][11] Category Diameter
(km)
Mass
(1020 kg)
Average distance
from the Sun (AU)[1]
136199 Eris −1.19 SDO 2326±12 167 68
134340 Pluto −0.70 plutino 2306±20 130 39
136472 Makemake −0.42 cubewano 1478±17 ≈ 30 46
136108 Haumea 0.05 haumeid 1240+69
−58
40 43

Between 1 and 3[edit]

These TNOs are estimated to be around 1,000 kilometres (620 mi) across, and have theoretical minimum diameters of at least 334 kilometres (208 mi). Brown categorizes most of these with the dwarf planets accepted by the IAU, and Tancredi has recommended to the IAU that they accept them as dwarf planets[12] (apart from 2007 OR10, which he did not consider, and 2013 FY27, which was not yet discovered at the time).

Name H[10][11] Category Diameter
(km)
Mass
(1020 kg)
Average distance
from the Sun (AU)[1]
90377 Sedna 1.83 Detached object 995±80 ≈ 10 519
(225088) 2007 OR10 1.92 SDO 1280±210  ? 67
90482 Orcus 2.30 plutino 917±25 6.3[13] 39
50000 Quaoar 2.48 cubewano 1110±5 14±1 44
2013 FY27 2.98 SDO 761–850 (assumed) 60

Between 3 and 4[edit]

These minor planets have theoretical minimum diameters of 213–336 km. Ceres is officially accepted as a dwarf planet.

Name H[10][11] Category Diameter
(km)
Mass
(1020 kg)
Average distance
from the Sun (AU)[1]
4 Vesta 3.20 asteroid 525.4±0.2[14] 2.59[15] 2.361
28978 Ixion 3.20 plutino 650+260
−220
≈ 3? 39.65
(55636) 2002 TX300 3.21 haumeid 286±10 ≈ 0.12 43.11
(55565) 2002 AW197 3.26 cubewano 768+39
−38
≈ 4? 47.30
1 Ceres 3.36 asteroid 950±3 9.43±0.07 2.767
(202421) 2005 UQ513 3.40 cubewano 498+63
−75
43
(229762) 2007 UK126 3.44 SDO 599±77 73
174567 Varda 3.49 cubewano 705+81
−75
45.94
(55637) 2002 UX25 3.60 cubewano 697+23
−25
≈ 3.3? 42.53
20000 Varuna 3.70 cubewano 936+238
−324
[16]
≈3.7? 42.90
(303775) 2005 QU182 3.73 SDO 416±73 113
2010 EK139 3.76 SDO 470+35
−10
69.4
(307261) 2002 MS4 3.77 cubewano 934±47 41.90
(84522) 2002 TC302 3.78 5:2 SDO 584+106
−88
[17]
≈15? 55.02
2006 QH181 3.80 semi-detached 760 (assumed) 67.3
(145452) 2005 RN43 3.85 cubewano 679+55
−73
41.53
(90568) 2004 GV9 3.90 cubewano 677±70 1.1–5.0 42.23
(278361) 2007 JJ43 3.9 cubewano ≈ 700 47.99
2010 KZ39 3.94 SDO 644 (assumed) 45.0
(120178) 2003 OP32 3.95 haumeid ≈ 230 43.24

Between 4 and 5[edit]

These minor planets have theoretical minimum diameters of 134–212 km:

Name H[18] Category Diameter (km) Mass
(1020 kg)
Average distance
from the Sun (AU)[1]
by [1] by [19] others
(145453) 2005 RR43 4.00 haumeid 697 252 km 43
(208996) 2003 AZ84 4.00 plutino 710 686 590–785 km[20] 39.45
(230965) 2004 XA192 4.00 cubewano 696 46.98
(84922) 2003 VS2 4.01 plutino 629 636 523.0+35.1
−34.4
[21]
39.27
(42301) 2001 UR163 4.05 9:4 SDO 620 636 51.40
2012 VP113 4.1 Detached object 586 315–640 km 263.3
2 Pallas 4.13 asteroid (582×556×500) ± 9 km[8] 2.11±0.26[22] 2.772
2010 RE64 4.2 cubewano 380–860[23] 45.8
2010 RF43 4.2 cubewano 380–860[23] 46.5
120347 Salacia 4.2 cubewano 560 548 854±45[17] 4.5±0.2 41.97
(175113) 2004 PF115 4.2 plutino 505 39.18
2003 UZ413 4.3 plutino 591
(120348) 2004 TY364 4.3 other TNO 540 554 38.72
2013 FZ27[24] 4.4 other TNO 280–600 km[23] 48.4
2010 VR11 4.4 cubewano 350–784[23] 44.4
2010 FX86 4.4 cubewano 580 350–784[23] 44.05
(386723) 2009 YE7 4.4 haumeid 210-584 54.2
2008 ST291 4.4 SDO 583 350–784[23] 106
(145451) 2005 RM43 4.4 SDO 560 580 89.73
2004 NT33 4.4 cubewano 580
2004 XR190 4.47 SDO 540 572 57.36
(119951) 2002 KX14 4.5 cubewano? 560 560 <560(?)[20] 39.01
(144897) 2004 UX10 4.5 plutino 529 39.1
(19308) 1996 TO66 4.56 haumeid 540 900 200 km 43.19
2010 VZ98 4.7 cubewano 305–680[23] 43.2
2001 QF298 4.7 plutino 490 420 39.30
(26375) 1999 DE9 4.7 2:5 TNO 490 461 461±45[20] 1? 55.72
38628 Huya 4.7 plutino 480 506 532±25[20] 1.6? 39.76
(145480) 2005 TB190 4.7 detached 505 76.38
(47171) 1999 TC36 4.73 plutino 440 A1=286+45
−38
A2=265+41
−35
0.12[25] 39.27
2007 JH43 4.7 plutino 522 39.56
2003 QX113 4.7 detached 450 505 49.9
(24835) 1995 SM55 4.8 haumeid 470 702 174 km 41.64
(120132) 2003 FY128 4.8 detached 430 440 49.77
(82075) 2000 YW134 4.8 8:3 TNO 430 431 57.77
19521 Chaos 4.9 cubewano 450 745 45.56
2002 XV93 4.9 plutino 430 457 39.22
2002 CY248 4.9 cubewano 410 440 46.18
2008 OG19 4.9 SDO 461 67
2000 CN105 5.0 cubewano 430 440 44.65

Probable per Brown[edit]

Mike Brown considers a large number of trans-Neptunian bodies, ranked by estimated size, to be "probably" dwarf planets.[26] He did not consider asteroids, stating "In the asteroid belt Ceres, with a diameter of 900 km, is the only object large enough to be round".[26]

The terms for varying degrees of likelihood he split these into:

  • Near certainty: diameter estimated/measured to be over 900 kilometres (560 mi). Sufficient confidence to say these must be in hydrostatic equilibrium, even if predominantly rocky.
  • Highly likely: diameter estimated/measured to be over 600 kilometres (370 mi). The size would have to be "grossly in error" or they would have to be primarily rocky to not be dwarf planets.
  • Likely: diameter estimated/measured to be over 500 kilometres (310 mi). Uncertainties in measurement mean that some of these will be significantly smaller and thus doubtful.
  • Probable: diameter estimated/measured to be over 400 kilometres (250 mi). Expected to be dwarf planets, if they are icy, and that figure is correct.
  • Possible: diameter estimated/measured to be over 200 kilometres (120 mi). Icy moons transition from a round to irregular shape in the 200–400 km range, suggesting that the same figure holds true for KBOs. Thus, some of these objects could be dwarf planets.
  • Probably not: diameter estimated/measured to be under 200 km. No icy moon under 200 km is round, suggesting that the same figure holds true for KBOs. The estimated size of these objects would have to be in error for them to be dwarf planets.

For the table below, all sizes are estimates. Occultation probably gives the most exact estimate. In cases without measurement, the "typical" albedo for an object is assumed from its absolute magnitude, and the size estimate is computed using these values.

Likely Trans-Neptunian dwarf planets (as of 2014 June 16)[26]
rank name diameter
(km)
albedo
(%)
absolute
magnitude
(H)
comments likelihood category
1 136199 Eris 2330 99 −1.1 (occultation) near certainty SDO
2 134340 Pluto 2329 64 −0.7 (occultation) near certainty plutino
3 136472 Makemake 1426 81 0.1 (occultation) near certainty cubewano
4 (225088) 2007 OR10 1290 19 2.0 (radiometric) near certainty 10:3 TNO
5 136108 Haumea 1252 80 0.4 1920 × 1540 × 990
(inferred:lightcurve,
mass, radiometry)
near certainty haumeid
6 50000 Quaoar 1092 13 2.7 (radiometric) near certainty cubewano
7 90377 Sedna 1041 32 1.8 (radiometric) near certainty sednoid
8 90482 Orcus 983 23 2.3 (radiometric) near certainty plutino
9 (307261) 2002 MS4 960 5 4.0 (radiometric) near certainty cubewano
10 120347 Salacia 921 4 4.2 (radiometric) near certainty cubewano
11 20000 Varuna 768 9 3.9 (radiometric) highly likely cubewano
12 2013 FY27 764 15 3.3 (large/estimated) highly likely SDO
13 (208996) 2003 AZ84 747 11 3.7 (radiometric) highly likely plutino
14 (55637) 2002 UX25 704 11 3.9 (radiometric) highly likely cubewano
15 (90568) 2004 GV9 703 8 4.2 (radiometric) highly likely cubewano
16 (55565) 2002 AW197 703 12 3.8 (radiometric) highly likely cubewano
17 (145452) 2005 RN43 697 11 3.9 (radiometric) highly likely cubewano
18 174567 Varda 694 13 3.7 (large/estimated) highly likely cubewano
19 (202421) 2005 UQ513 694 13 3.7 (large/estimated) highly likely cubewano
20 28978 Ixion 674 12 3.8 (radiometric) highly likely plutino
21 (278361) 2007 JJ43 616 10 4.2 (large/estimated) highly likely cubewano
22 (229762) 2007 UK126 612 17 3.7 (radiometric) highly likely SDO
23 19521 Chaos 612 5 5.0 (radiometric) highly likely cubewano
24 2012 VP113 602 10 4.3 (large/estimated) highly likely sednoid
25 (230965) 2004 XA192 602 10 4.3 (large/estimated) highly likely cubewano
26 2010 KZ39 602 10 4.3 (large/estimated) highly likely cubewano? detached object?
27 2013 FZ27 602 10 4.3 (large/estimated) highly likely other resonant TNO? SDO?
28 (84522) 2002 TC302 591 12 4.2 (radiometric) likely 5:2 TNO
29 2010 RF43 588 10 4.4 (large/estimated) likely cubewano
30 (78799) 2002 XW93 584 4 5.4 (radiometric) likely centaur
31 (42301) 2001 UR163 574 9 4.5 (large/estimated) likely 9:4 TNO
32 2003 UZ413 574 9 4.5 (large/estimated) likely plutino
33 2002 XV93 564 4 5.4 (radiometric) likely plutino
34 2006 QH181 560 9 4.6 (large/estimated) likely 10:3 TNO
35 2008 ST291 560 9 4.6 (large/estimated) likely SDO
36 2010 RE64 560 9 4.6 (large/estimated) likely cubewano
37 2010 FX86 560 9 4.6 (large/estimated) likely cubewano
38 (145451) 2005 RM43 547 9 4.7 (large/estimated) likely SDO
39 2004 XR190 547 9 4.7 (large/estimated) likely SDO
40 2004 NT33 547 9 4.7 (large/estimated) likely cubewano
41 (84922) 2003 VS2 537 15 4.1 (radiometric) likely plutino
42 (120348) 2004 TY364 534 8 4.8 (large/estimated) likely other TNO
43 2008 OG19 522 8 4.9 (large/estimated) likely SDO
44 2010 VK201 522 8 4.9 (large/estimated) likely cubewano?
45 (308379) 2005 RS43 513 4 5.5 (blue/estimated) likely twotino
46 2003 QX113 509 7 4.9 (large/estimated) likely other TNO? detached?
47 2007 JH43 509 7 4.9 (large/estimated) likely plutino

Another 37 objects were listed as "probable" dwarfs, and another 269 objects were listed as "possible" dwarfs, depending on composition and the accuracy of size and mass estimates.[26]

Probable per Tancredi[edit]

In 2010, Gonzalo Tancredi presented a report to the IAU evaluating a list of 46 candidates for dwarf-planet status based on light curve amplitude analysis and the assumption that the object was more than 450 kilometres (280 mi) in diameter. Some diameters are measured, some are best-fit estimates, and others use an assumed albedo of 0.10. Of these, he identified 15 as dwarf planets by his criteria, with another nine being considered possible. To be cautious, he advised the IAU to "officially" accept as dwarf planets the top three: Sedna, Orcus, and Quaoar.[12] Although the IAU had anticipated Tancredi's recommendations, as of 2013, they had not responded.

Probable plutoids (as of 2009)
name absolute
magnitude
(H)
diameter
(km)
likelihood
136199 Eris −1.1 2600 accepted (measured)
134340 Pluto −0.7 2390 accepted (measured)
136472 Makemake 0 1500 accepted
136108 Haumea 0.5 1150 accepted
90377 Sedna 1.8 1600 accepted (and recommended)
90482 Orcus 2.5 946 accepted (and recommended)
50000 Quaoar 2.6 908 accepted (and recommended)
(55636) 2002 TX300 3.49 800* accepted
(55565) 2002 AW197 3.61 735 accepted
(208996) 2003 AZ84 3.71 686 accepted
28978 Ixion 3.84 650 accepted
20000 Varuna 3.99 500 accepted
(90568) 2004 GV9 4.2 677 accepted
38628 Huya 5.23 533 accepted
(15874) 1996 TL66 5.46 575 accepted
174567 Varda 3.6 801# possible
(145452) 2005 RN43 3.9 697# possible
(145453) 2005 RR43 4 666* possible
(120178) 2003 OP32 4.1 636* possible
(42301) 2001 UR163 4.2 607# possible
120347 Salacia 4.2 607# possible
(145451) 2005 RM43 4.4 554# possible
(144897) 2004 UX10 4.5 529# possible
(26375) 1999 DE9 4.7 482 possible

* In 2009, Mike Brown wrote that (55636) 2002 TX300 was a Haumea family member with a diameter less than 400 km.[27] An occultation of a star on October 9, 2009, produced a diameter of 286 kilometers, indicating an albedo of about 0.88.[28] (145453) 2005 RR43 and (120178) 2003 OP32 are also suspected members of the Haumea family and so are likely to be substantially smaller than the figures here.

# Diameter estimated from assumed albedo.

Spitzer alpha candidates[edit]

Calculation of the diameter of Ixion depends on the albedo (the fraction of light that it reflects), which is currently unknown.

In 2007, observations using the Spitzer Space Telescope were used to calculate the sizes of several large TNOs. The following were found to be greater than 600 kilometres (370 mi) in diameter.[20] ( 2007 OR10 is not included because it was not observed by Spitzer.) Although (84522) 2002 TC302 has a dim absolute magnitude, it is placed high on the list because it was believed to have a low albedo.

Name (H) Spitzer
Size (km)
Spitzer
Albedo
V–R
136199 Eris −1.1 2600+400
−200
0.70+0.15
−0.20
90377 Sedna 1.6 < 1600 > 0.16 0.78
136472 Makemake 0.0 1500+400
−200
0.80+0.10
−0.20
136108 Haumea 0.5 1150+250
−100
0.84+0.10
−0.20
(84522) 2002 TC302 3.8 1145±331 0.03+0.03
−0.01
0.67
90482 Orcus 2.3 946±73 0.20±0.03 0.37
50000 Quaoar 2.5 844±198 0.20+0.13
−0.07
0.64
(55565) 2002 AW197 3.2 735±112 0.12+0.04
−0.03
0.56
(84922) 2003 VS2 4.0 725±193 0.06+0.05
−0.02
0.59
(307261) 2002 MS4 3.8 726±123 0.08+0.04
−0.02
0.38
(208996) 2003 AZ84 4.0 686±97 0.12+0.04
−0.03
0.36
(55637) 2002 UX25 3.6 681±115 0.12+0.05
−0.03
0.57
(90568) 2004 GV9 3.9 677±70 0.08+0.02
−0.01
0.52
28978 Ixion 3.2 573±141 0.16+0.12
−0.06
0.61

See also[edit]

References[edit]

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  3. ^ a b Dan Bruton. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics & Astronomy (Stephen F. Austin State University). Retrieved 2008-06-13. 
  4. ^ "IAU 2006 General Assembly: Result of the IAU Resolution votes". International Astronomical Union. 2006. Retrieved 2008-01-26. 
  5. ^ "Dwarf Planets". NASA. Retrieved 2008-01-22. 
  6. ^ "Plutoid chosen as name for Solar System objects like Pluto" (Press release). 
  7. ^ "AstDys (47171) 1999TC36 Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2009-12-07. 
  8. ^ a b Savage, Don; Jones, Tammy; Villard, Ray (1995-04-19). "Asteroid or Mini-Planet? Hubble Maps the Ancient Surface of Vesta". Hubble Site News Release STScI-1995-20. Retrieved 2006-10-17. 
  9. ^ "JPL Small-Body Database Search Engine: orbital class (TNO) and H < 6 (mag)". JPL Solar System Dynamics. Retrieved 2013-12-21. 
  10. ^ a b c "List Of Centaurs and Scattered-Disk Objects". Minor Planet Center. 
  11. ^ a b c "List Of Transneptunian Objects". Minor Planet Center. 
  12. ^ a b Tancredi, G. (2010). "Physical and dynamical characteristics of icy "dwarf planets" (plutoids)". Icy Bodies of the Solar System: Proceedings IAU Symposium No. 263, 2009. 
  13. ^ Brown, M.E.; Ragozzine, D.; Stansberry, J.; Fraser, W.C. (2009). "The size, density, and formation of the Orcus-Vanth system in the Kuiper belt". AJ. arXiv:0910.4784. Bibcode:2010AJ....139.2700B. doi:10.1088/0004-6256/139/6/2700. 
  14. ^ Russell, C. T.; et al. (2012). "Dawn at Vesta: Testing the Protoplanetary Paradigm". Science 336 (6082): 684. Bibcode:2012Sci...336..684R. doi:10.1126/science.1219381. 
  15. ^ Baer, James; Chesley, Steven R. (2008). "Astrometric masses of 21 asteroids, and an integrated asteroid ephemeris" (PDF). Celestial Mechanics and Dynamical Astronomy (Springer Science+Business Media B.V. 2007) 100 (2008): 27–42. Bibcode:2008CeMDA.100...27B. doi:10.1007/s10569-007-9103-8. Retrieved 2008-11-11. 
  16. ^ W. M. Grundy, K. S. Noll, D. C. Stephens (2005). "Diverse albedos of small trans-neptunian objects". Icarus (journal) 176 (1): 184–191. arXiv:astro-ph/0502229. Bibcode:2005Icar..176..184G. doi:10.1016/j.icarus.2005.01.007. 
  17. ^ a b S. Fornasier, E. Lellouch, T. Müller, P. Santos-Sanz, P. Panuzzo, C. Kiss, T. Lim, M. Mommert, D. Bockelée-Morvan, E. Vilenius, J. Stansberry, G.P. Tozzi, S. Mottola, A. Delsanti, J. Crovisier, R. Duffard, F. Henry, P. Lacerda, A. Barucci, & A. Gicquel (2013). TNOs are Cool: A survey of the trans-Neptunian region. VIII. Combined Herschel PACS and SPIRE observations of 9 bright targets at 70–500 µm.
  18. ^ "JPL Small-Body Database Browser". Jet Propulsion Laboratory. 
  19. ^ Robert Johnston. "List of Known Trans-Neptunian Objects". Retrieved 2010-08-07. 
  20. ^ a b c d e Barucci, M.A.; Stansberry, John; Grundy, Will; Brown, Mike; Cruikshank, Dale; Spencer, John; Trilling, David; Margot, Jean-Luc (2007). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope". Kuiper Belt. arXiv:astro-ph/0702538. Bibcode:2008ssbn.book..161S. 
  21. ^ Mommert, Michael; Harris, A. W.; Kiss, C.; Pál, A.; Santos-Sanz, P.; Stansberry, J.; Delsanti, A.; Vilenius, E.; Müller, T. G.; Peixinho, N.; Lellouch, E.; Szalai, N.; Henry, F.; Duffard, R.; Fornasier, S.; Hartogh, P.; Mueller, M.; Ortiz, J. L.; Protopapa, S.; Rengel, M.; Thirouin, A. (May 2012). "TNOs are cool: A survey of the trans-Neptunian region—V. Physical characterization of 18 Plutinos using Herschel-PACS observations". Astronomy & Astrophysics 541: A93. arXiv:1202.3657. Bibcode:2012A&A...541A..93M. doi:10.1051/0004-6361/201118562.  edit
  22. ^ Baer, James; Steven R. Chesley (2008). "Astrometric masses of 21 asteroids, and an integrated asteroid ephemeris" (PDF). Celestial Mechanics and Dynamical Astronomy (Springer Science+Business Media B.V. 2007) 100 (2008): 27–42. Bibcode:2008CeMDA.100...27B. doi:10.1007/s10569-007-9103-8. Retrieved 2008-11-11. 
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  24. ^ "2013 FZ27 Orbit". Minor Planet Center. Retrieved 2014-04-06. 
  25. ^ Benecchi, S.D; Noll, K. S.; Grundy, W. M.; Levison, H. F. (2009). "(47171) 1999 TC36, A Transneptunian Triple". Icarus. arXiv:0912.2074. Bibcode:2010Icar..207..978B. doi:10.1016/j.icarus.2009.12.017. 
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External links[edit]