Transneptunian object
A trans- Neptunian object ( TNO ) or, more rarely, Trans - Neptune is the name given to all celestial bodies in the solar system whose central orbit (major semi-axis ) lies beyond the orbit of the outermost gas planet Neptune .
In Kuiper belt objects located are a subset of the TNO, and (also as Kuiper belt objects KBO , of English belt Kuiper object ), respectively. Today, around 3300 TNOs are known, but a few tens of thousands of objects are believed to have a diameter of more than 100 km.
history
From around 1900 to 1930 the word "Transneptune" stood for a hypothetical ninth planet that was (erroneously) held responsible for small orbital disturbances of the planets Uranus and Neptune. The Mars explorer Percival Lowell had been looking for him for a long time and had financed the “ Lowell Observatory ” near Flagstaff.
Discovered on February 18, 1930, Pluto is the only Trans-Neptunian object that was considered a planet for a period of time . However, Pluto was downgraded to dwarf planet rank in 2006 . From around 1950 onwards the search for a transpluto was made , but in 1977, after the discovery of the first centaur Chiron , a different terminology was chosen .
Many Trans-Neptunian objects are not very large, dark, and difficult to see. The exploration of the Trans-Neptunian objects is still in its infancy. Many objects are rediscovered every year. New and larger telescopes and computer-aided image analysis enable new knowledge about these objects in quick succession. The New Horizons space probe was able to examine Pluto and the Kuiper Belt more closely and thus brought new knowledge about this area of the solar system.
properties
The previously discovered trans-Neptunian objects are comet-like in their composition. According to orbital measurements since the 1970s, many known comets come from the Kuiper Belt rather than, as has long been assumed, from the Oort cloud .
The Transneptune are considered to be a special group of asteroids and differ from those in the main belt mainly in that they are
- their orbits further away from the sun and often very elongated
- their often charcoal dark color ( albedo only about 0.04 - 0.2)
- their composition of loose rock and ice , which at the same time represents the transition to cometary nuclei.
Object types
Most of the Transneptunes orbit the sun in the Kuiper Belt between 30 and 55 AU and are divided into different groups based on their orbits.
Resonant KBO
A third of all Kuiper belt objects have different orbital resonances to the planet Neptune . Their orbital times are therefore in a simple numerical relationship to that of Neptune of 164.79 years. According to Kepler's third law , objects with the same orbital resonance also have semiaxes of similar size. The other orbital elements such as their shape (eccentricity) and their position ( inclination , length of the ascending node and argument of the periapsis ) are very different. Frequent responses are:
resonance | Orbital period 1 ( years) |
major semi-axis 1 ( AE) | designation | Examples |
---|---|---|---|---|
2: 3 | 247 | 39.4 | Plutino | (134340) Pluto , (28978) Ixion , (38628) Huya , (84922) 2003 VS 2 , (90482) Orcus , (208996) 2003 AZ 84 |
3: 5 | 275 | 42.3 | (15809) 1994 JS , (126154) 2001 YH 140 , (143751) 2003 US 292 | |
4: 7 | 288 | 43.6 | (118378) 1999 HT 11 , (118698) 2000 OY 51 , (119070) 2001 KP 77 , (119956) 2002 PA 149 , (469306) 1999 CD 158 | |
1: 2 | 330 | 47.7 | Twotino | (20161) 1996 TR 66 , (26308) 1998 SM 165 , (119979) 2002 WC 19 , (130391) 2000 JG 81 , (137295) 1999 RB 216 |
2: 5 | 412 | 55.4 | (69988) 1998 WA 31 , (84522) 2002 TC 302 , (119068) 2001 KC 77 , (135571) 2002 GG 32 , (143707) 2003 UY 117 | |
1: 3 | 494 | 62.5 | (136120) 2003 LG 7 , (385607) 2005 EO 297 |
The Plutinos are named after their first discovered member, Pluto. Twotinos are a modification of this term according to the ratio 2: 1.
Classic KBO (Cubewanos)
The Cubewanos (or “classic KBO”, CKBO) are an even more numerous category . The group is named after the first discovered object of this group Albion (formerly "1992 QB 1 "). The objects move with small eccentricities on almost circular paths between 42 and 50 AU with orbit inclinations of up to 30 °. About 2/3 of the known KBO move on such a circle-like orbit around the sun. This group includes the 1000 km Quaoar and Varuna properties . Classic KBO have no orbital resonance with the outer planets.
Scattered KBO
Scattered KBO (or Scattered Disk Objects , SDO) move with large eccentricities on paths with perihelion distances of close to 35 AU and apheld distances of up to a few hundred AU. So far, around 500 of these scattered KBOs are known (for example (15874) 1996 TL 66 with a strongly elliptical orbit and an orbit inclination of 24 °), probably only a tiny fraction of the actually existing ones.
Detached Objects
The orbits of some Trans-Neptunian objects cannot be explained by Neptune scattering alone. These "detached objects" (DO) or "Distant Detached Objects" (DDO) have perihelion distances of more than 40 AU, which cannot be caused by Neptune's gravity. The explanations include a disturbance from outside the Kuiper belt, e.g. B. by a passing star or a planet located outside the belt. About 60 are currently known.
Sednoids
At the end of 2003 an object (90377) Sedna was discovered at three times the distance from Pluto, which moves on an extremely elongated ellipse far outside the Kuiper belt, but not yet in the Oort cloud, and represents a new prototype. It is around 995 km in size and was named after the central sea goddess of the Inuit Sedna . In 2012 VP 113 and a few other objects with similar orbit elements were found. The alignment of their apsidal lines and their similar inclination led Konstantin Batygin and Michael E. Brown to the conclusion that an as yet undiscovered “ Planet Nine ” enforces the uniform alignment of the orbits of this DDO.
object |
Orbital period T (years) |
Semi-axis a (AE) |
Perihelion q (AE) |
Aphelion Q (AE) |
eccentricity e |
Argument of the periapsis ? (°) |
Inclination i (°) |
Length of the rise Node Ω (°) |
Perihelion π = ω + Ω (°) |
Absolute brightness H (mag) |
---|---|---|---|---|---|---|---|---|---|---|
(90377) Sedna | 10,590 | 482.24 | 76.08 | 888.39 | 0.84 | 311.6 | 11.9 | 144.4 | 96.0 | 1.5 |
(474640) 2004 VN 112 | 5,602 | 315.41 | 47.31 | 583.51 | 0.85 | 326.9 | 25.6 | 66.0 | 32.9 | 6.5 |
(523622) 2007 TG 422 | 10.165 | 469.26 | 35.55 | 902.96 | 0.92 | 285.6 | 18.6 | 112.9 | 38.5 | 6.5 |
2010 GB 174 | 6,824 | 359.75 | 48.79 | 670.72 | 0.86 | 347.7 | 21.6 | 130.8 | 118.5 | 6.5 |
2012 VP 113 ("Biden") | 4.106 | 256.40 | 80.44 | 432.37 | 0.69 | 293.6 | 24.1 | 90.7 | 24.3 | 4.0 |
2013 FT 28 | 5,558 | 313.77 | 43.52 | 584.02 | 0.86 | 40.3 | 17.3 | 217.8 | 258.1 | 6.7 |
2013 RF 98 | 6,556 | 350.30 | 36.08 | 664.52 | 0.90 | 311.7 | 29.6 | 67.6 | 19.3 | 8.7 |
2013 SY 99 ("uo3l91") | 17,604 | 676.71 | 49.96 | 1,303.45 | 0.93 | 32.3 | 4.2 | 29.5 | 61.8 | 6.7 |
2014 FE 72 | 101.195 | 2,171.57 | 36.28 | 4,306.86 | 0.98 | 134.3 | 20.6 | 336.8 | 111.1 | 6.1 |
2014 SR 349 | 5,064 | 294.90 | 47.65 | 542.14 | 0.84 | 341.1 | 18.0 | 34.8 | 15.9 | 6.7 |
2015 GT 50 ("o5p060") | 6,073 | 332.85 | 38.46 | 627.24 | 0.88 | 129.3 | 8.8 | 46.1 | 175.4 | 8.5 |
2015 KG 163 ("o5m52") | 23,718 | 825.50 | 40.50 | 1,610.50 | 0.95 | 32.0 | 14.0 | 219.1 | 251.1 | 8.2 |
2015 RX 245 ("o5t52") | 8,210 | 406.96 | 45.52 | 768.40 | 0.89 | 65.3 | 12.2 | 8.6 | 73.9 | 6.2 |
2015 BP 519 ("Caju") | 8,932 | 430.48 | 35.14 | 825.81 | 0.92 | 348.4 | 54.1 | 135.2 | 123.6 | 4.4 |
(541132) Leleākūhonua | 36,182 | 1,093.94 | 64.94 | 2,122.94 | 0.94 | 118.2 | 11.6 | 300.8 | 59.0 | 5.3 |
Known objects
The brightest known TNO (with absolute brightness ≤ 4.0):
Surname | Proper name |
preliminary reference | Provisional designation |
M V | Absolute brightness |
A. | Albedo |
D. | Equatorial diameter (in km) |
a | Major semi-axis (in AU ) |
e | Numerical eccentricity |
i | Orbit inclination (in degrees) |
T | Orbital period (in earth years) |
Size | group
|
EJ | Year of discovery |
Surname | preliminary reference | M V | A. | D. | a | e | i | T | Size | EJ |
---|---|---|---|---|---|---|---|---|---|---|
(134340) Pluto | −1.0 | 0.49-0.66 | 2370 | 39.48 | 0.249 | 17.2 | 247.94 | PLU | 1930 | |
(136199) Eris | 2003 UB 313 | −1.1 | 0.85 ± 0.07 | 2326 | 67.73 | 0.441 | 44.1 | 556.41 | SDO | 2005 |
(136472) Makemake | 2005 FY 9 | −0.3 | 0.77 ± 0.03 | 1502 ± 45 equ × 1430 ± 9 pol | 45.75 | 0.155 | 29.0 | 309.41 | KBO | 2005 |
(136108) Haumea | 2003 EL 61 | 0.2 | 0.8 ± 0.07 | 1920 × 1540 × 990 | 43.27 | 0.190 | 28.2 | 284.61 | KBO | 2005 |
(90377) Sedna | 2003 VB 12 | 1.5 | 0.32 ± 0.06 | 995 ± 80 | 515 | 0.852 | 11.9 | 11,929 | ANO | 2003 |
(225088) Gong gong | 2007 OR 10 | 1.8 | 0.089 +0.031−0.009 | 1535 +75-225 | 67.06 | 0.506 | 30.9 | 549.16 | SDO | 2007 |
(90482) Orcus | 2004 DW | 2.2 | 0.23 | 917 ± 25 | 39.47 | 0.218 | 20.6 | 247.97 | PLU | 2004 |
(50000) Quaoar | 2002 LM 60 | 2.4 | 0.10 ± 0.03 | 1100 ± 5 | 43.32 | 0.035 | 8.0 | 285.09 | CKBO | 2002 |
(174567) Varda | 2003 MW 12 | 3.3 | 0.102 ± 0.024 | 705 ± 75 | 45.74 | 0.140 | 21.5 | 309.41 | KBO | 2003 |
(55636) | 2002 TX 300 | 3.4 | 0.88 +0.015−0.008 | 286 ± 10 | 43.16 | 0.121 | 25.9 | 283.56 | CKBO | 2002 |
(202421) | 2005 UQ 513 | 3.4 | 0.202 +0.084−0.049 | +63−75 | 49843.24 | 0.150 | 25.7 | 284.37 | CKBO | 2005 |
(55565) | 2002 AW 197 | 3.4 | 0.112 ± 0.012 | 768 ± 38 | 47.52 | 0.131 | 24.3 | 327.64 | CKBO | 2002 |
(229762) Gǃkúnǁ'hòmdímà | 2007 UK 126 | 3.5 | 0.167 +0.058−0.038 | 614 ± 15 | 73.81 | 0.492 | 23.3 | 634 | SDO (DO) | 2007 |
(28978) Ixion | 2001 KX 76 | 3.6 | 0.141 ± 0.011 | 617 ± 19 | 39.46 | 0.242 | 19.6 | 249.89 | PLU | 2001 |
(20000) Varuna | 2000 WR 106 | 3.7 | 0.127 ± 0.04 | +154−86 | 66843.16 | 0.051 | 17.2 | 283.56 | CKBO | 2000 |
(307261) | 2002 MS 4 | 3.7 | 0.051 +0.036−0.022 | 934 ± 47 | 41.68 | 0.146 | 17.7 | 269.06 | KBO | 2002 |
(208996) | 2003 AZ 84 | 3.7 | 0.107 +0.023−0.016 | 727 ± 65 | 39.66 | 0.176 | 13.6 | 249.79 | KBO | 2003 |
(145452) | 2005 RN 43 | 3.7 | 0.11 | +55−73 | 67941.36 | 0.019 | 19.3 | 265.98 | CKBO? | 2005 |
(55637) | 2002 UX 25 | 3.8 | 0.107 + 0.005−0.008 | 665 ± 29 | 42.66 | 0.144 | 19.5 | 278.60 | CKBO | 2002 |
(84522) | 2002 TC 302 | 3.9 | 0.115 + 0.047−0.033 | +105−88 | 58455.36 | 0.296 | 35.1 | 412 | SDO | 2002 |
(120347) Salacia | 2004 SB 60 | 3.9 | 0.035 +0.010−0.007 | 854 ± 45 | 41.88 | 0.108 | 23.9 | 271.00 | KBO | 2004 |
(278361) | 2007 JJ 43 | 3.9 | 0.13 +0.09−0.07 | +170−140 | 61048.27 | 0.163 | 12.0 | 335.40 | KBO | 2007 |
(90568) | 2004 GV 9 | 4.0 | 0.0770 + 0.0084−0.0077 | 680 ± 34 | 42.12 | 0.081 | 22.0 | 273.38 | CKBO? | 2004 |
2010 concentration camp 39 | 4.0 | 0.10 | 600 estimated | 45.11 | 0.056 | 26.1 | 302.97 | CKBO? | 2010 | |
2012 VP 113 | 4.0 | 0.2 estimated | 450 estimated | 261 | 0.691 | 24.0 | 4,200 | ANO | 2012 | |
(230965) | 2004 XA 192 | 4.2 | 0.26 + 0.34−0.15 | +120−95 | 33947.29 | 0.250 | 38.1 | 325.23 | KBO | 2004 |
See also
literature
- David C. Jewitt et al. a .: Trans-Neptunian objects and comets. Springer, Berlin 2008, ISBN 978-3-540-71957-1 .
- John K. Davies: Beyond Pluto - exploring the outer limits of the solar system. Cambridge Univ. Press, Cambridge 2001, ISBN 0-521-80019-6 .
- Alan Fitzsimmons et al. a .: Minor bodies in the outer solar system. Springer, Berlin 2001, ISBN 3-540-41152-6 .
Web links
- Astro Corner: Trans-Neptune Objects
- List Of Transneptunian Objects (English)
Individual evidence
- ↑ Pluto the problematic planet. In: David Baker, Todd Ratcliff: Extreme Places. Rowohlt, 2010, ISBN 978-3-498-00660-0 , pp. 198 f.
- ↑ List of classified objects in the MPC October 2008.
- ↑ Morbidelli, Alessandro; Levison, Harold F. (November 2004). Scenarios for the Origin of the Orbits of the Trans-Neptunian Objects 2000 CR105 and 2003 VB12 . The Astronomical Journal 128 (5): 2564-2576. arxiv : astro-ph / 0403358
- ↑ Rodney S. Gomes; Matese, J; Lissauer, J (2006). A distant planetary-mass solar companion may have produced distant detached objects . Icarus (Elsevier) 184 (2): 589-601. doi: 10.1016 / j.icarus.2006.05.026
- ^ K. Batygin, ME Brown: Evidence for a Distant Giant Planet in the Solar System. In: The Astronomical Journal. Volume 151, No. 2, 2016, pp. 22-34, doi: 10.3847 / 0004-6256 / 151/2/22
- ↑ Website of the Minor Planet Center (MPC), list of objects with q> 30 and a> 250. International Astronomical Union (IAU), accessed January 19, 2020 .
- ↑ a b Róbert Szabó et al .: Pushing the Limits of K2: Observing Trans-Neptunian Objects. S3K2: Solar System Studies with K2 ( Memento of the original from March 5, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF)
- ^ Chadwick A. Trujillo , Scott S. Sheppard , A Sedna-like body with a perihelion of 80 astronomical units. In: Nature , 507 (7493), 2014, p. 471, doi: 10.1038 / nature13156
- ↑ E. Vilenius, C. Kiss, T. Müller, M. Mommert, P. Santos-Sanz, A. Pál, J. Stansberry, M. Mueller, N. Peixinho, E. Lellouch, S. Fornasier, A. Delsanti , A. Thirouin, JL Ortiz, R. Duffard, D. Perna, F. Henry: TNOs are Cool: A survey of the trans-Neptunian region. X. Analysis of classical Kuiper belt objects from Herschel * and Spitzer observations . (PDF) 2014, p. 13 (English)