Planetang unano
(Idinirekta mula sa Planetang duwende)
Ang planetang unano (Kastila: planeta enano, Ingles: dwarf planet) ayon sa International Astronomical Union (IAU), ay isang bagay sa kalangitan na umiikot palibot sa Araw na may sapat na bigat upang maging mabilog na dulot ng sariling balani ngunit hindi nalinis ang kalapit na rehiyon nito ng mga planetesimal at hindi isang satelayt.
Kasalukuyang miyembro
baguhinMga katangiang orbital ng mga planeta unano[1] | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Pangalan | Rehiyon ng Sistemang Solar |
Laki ng orbital (AU) |
Tagal ng rebolusyon (years) |
Mean orbital speed (km/s) |
Inclination to ecliptic (°) |
Orbital eccentricity |
Planetary discriminant | ||||
Ceres | Sinturong asteroyd | 2.77 | 4.60 | 17.882 | 10.59 | 0.080 | 0.33 | ||||
Pluto | Kuiper belt | 39.48 | 248.09 | 4.666 | 17.14 | 0.249 | 0.077 | ||||
Haumea | Kuiper belt | 43.34 | 285.4 | 4.484 | 28.19 | 0.189 | ? | ||||
Makemake | Kuiper belt | 45.79 | 309.9 | 4.419 | 28.96 | 0.159 | ? | ||||
Eris | Scattered disc | 67.67 | 557 | 3.436 | 44.19 | 0.442 | 0.10 |
Mga katangiang pisikal ng mga planeta unano | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pangalan | Diyametrong Ekwitoryal na malapit sa Moon |
Diyametrong Ekwatoryal (km) |
Bigat na malapit sa Buwan |
Bigat (×1021 kg) |
Densidad (g/cm3) |
Harapang grabidad (m/s2) |
Belosidad ng pagtakas (km/s) |
Inklanasyong Aksiyal |
Tagal ng pag-ikot (days) |
Buwan | Pang-ibabaw na Temperatura (K) |
Atmospera | |
Ceres[2][3] | 28% | 974.6±3.2 | 1.3% | 0.95 | 2.08 | 0.27 | 0.51 | ~3° | 0.38 | 0 | 167 | wala | |
Pluto[4][5] | 69% | 2306±10 | 17.8% | 13.05 | 2.0 | 0.58 | 1.2 | 119.59° | -6.39 | 3 | 44 | transient | |
Haumea[6][7] | 33% | 1150+250−100 | 5.7% | 4.2 ± 0.1 | 2.6–3.3 | ~0.44 | ~0.84 | 2 | 32 ± 3 | ? | |||
Makemake[6][8] | 43% | 1500+400−200 | ~5%? | ~4? | ~2? | ~0.5 | ~0.8 | 0 | ~30 | transient? | |||
Eris[6][9] | 75% | <2340 | 22.7% | 16.7 | 2.3 | ~0.8 | 1.3 | ~0.3 | 1 | 42 | pansamantala? | ||
Talababa
baguhin- ↑ Bowell, Ted. "The Asteroid Orbital Elements Database". Lowell Observatory. Nakuha noong 2008-02-12.
{{cite web}}
: CS1 maint: date auto-translated (link)[patay na link] - ↑ Thomas, P.C; Parker J.Wm.; McFadden, L.A.; atbp. (2005). "Differentiation of the asteroid Ceres as revealed by its shape". Nature. 437 (7056): 224–26. Bibcode:2005Natur.437..224T. doi:10.1038/nature03938. PMID 16148926.
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(tulong)CS1 maint: date auto-translated (link) CS1 maint: multiple names: mga may-akda (link) - ↑ Calculated based on the known parameters. APmag and AngSize generated with Horizons (Ephemeris: Observer Table: Quantities = 9,13,20,29)
- ↑ Williams, D.R. (2006-09-07). "Pluto Fact Sheet". NASA. Nakuha noong 2007-03-24.
{{cite web}}
: CS1 maint: date auto-translated (link) - ↑ Buie, M. W.; Grundy, W.M.; Young, E.F.; Young, L.A.; Stern, S.A. (2006). "Orbits and photometry of Pluto's satellites: Charon, S/2005 P1, and S/2005 P2". Astronomical Journal. 132: 290. doi:10.1086/504422. arXiv:astro-ph/0512491.
{{cite journal}}
: CS1 maint: date auto-translated (link) CS1 maint: multiple names: mga may-akda (link) - ↑ 6.0 6.1 6.2 Stansberry, J.; Grundy, W.; Brown, M.; atbp. (2007). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope" (abstract). The Journal of Business. arXiv:astro-ph/0702538.
{{cite journal}}
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(tulong)CS1 maint: date auto-translated (link) CS1 maint: multiple names: mga may-akda (link) - ↑ Rabinowitz, David L.; Barkume, K.M.; Brown, E.M.; atbp. (2006). "Photometric Observations Constraining the Size, Shape, and Albedo of 2003 EL61, a Rapidly Rotating, Pluto-Sized Object in the Kuiper Belt". The Astrophysical Journal. 639 (2): 1238–1251. doi:10.1086/499575. arXiv:astro-ph/0509401.
{{cite journal}}
: Explicit use of et al. in:|author2=
(tulong)CS1 maint: date auto-translated (link) CS1 maint: multiple names: mga may-akda (link) - ↑ J. Licandro, N. Pinilla-Alonso, M. Pedani; atbp. (2006). "The methane ice rich surface of large TNO 2005 FY9: a Pluto-twin in the trans-neptunian belt?". Astronomy and Astrophysics. 445 (L35–L38): L35. doi:10.1051/0004-6361:200500219. Nakuha noong 2008-07-14.
{{cite journal}}
: Explicit use of et al. in:|author=
(tulong)CS1 maint: date auto-translated (link) CS1 maint: multiple names: mga may-akda (link) - ↑ Brown, Michael E.; Schaller, Emily L. (2007). "The Mass of Dwarf Planet Eris". Science. 316 (5831): 1585. doi:10.1126/science.1139415. PMID 17569855.
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: CS1 maint: date auto-translated (link)
Mga kawing panlabas
baguhin- NPR: Dwarf Planets May Finally Get Respect (David Kestenbaum)
- BBC News: Q&A New planets proposal, August 16, 2006
- Ottawa Citizen: The case against Pluto Naka-arkibo 2007-02-24 sa Wayback Machine. (P. Surdas Mohit) August 24, 2006
- James L. Hilton, When Did the asteroids Become Minor Planets?Naka-arkibo 2016-06-12 sa Wayback Machine.
- NASA: IYA 2009 Dwarf Planets Naka-arkibo 2010-02-11 sa Wayback Machine.
- How Many Dwarfs Are There? (Mike Brown Dec 15, 2010)
Ang lathalaing ito na tungkol sa Astronomiya ay isang usbong. Makatutulong ka sa Wikipedia sa pagpapalawig nito.