Agfdhyk

This is a list of gravitationally rounded objects of the Solar System, which are objects that have a rounded, ellipsoidal shape due to the forces of their own gravity (hydrostatic equilibrium). Their sizes range from dwarf planets and moons to the planets and the Sun. This list does not include any small Solar System bodies, but it does include a sample of planetary-mass objects whose shape has yet to be accurately determined. The Sun's orbital characteristics are listed in relation to the Galactic Center, while all other objects are listed in order of their distance from the Sun.

Sun

The Sun is a G-type main-sequence star. It contains almost 99.9 percent of all the mass in the Solar System.^[1]

		Sun^[2]

Astronomical symbol^[q]
Mean distance from the Galactic Center	km light years	~2.5×10¹⁷ ~26,000
Mean radius	km :E^[f]	696,342 109.3
Surface area	km² :E^[f]	6.0877×10¹² 11,990
Volume	km³ :E^[f]	1.4122×10¹⁸ 1,300,000
Mass	kg :E^[f]	1.9855×10³⁰ 332,978.9
Gravitational parameter	m^3/s²	1.327×10²⁰
Density	g/cm³	1.409
Equatorial gravity	m/s²	274.0
Escape velocity	km/s	617.7
Rotation period	days^[g]	25.38
Orbital period about Galactic Center^[3]	million years	225–250
Mean orbital speed^[3]	km/s	~220
Axial tilt^[i] to the ecliptic	deg.	7.25
Axial tilt^[i] to the galactic plane	deg.	67.23
Mean surface temperature	K	5,778
Mean coronal temperature^[4]	K	1–2×10⁶
Photospheric composition		H, He, O, C, Fe, S

Planets

Key
* Terrestrial planet	° Gas giant	† Ice giant

A planet is defined according to the 2006 International Astronomical Union (IAU) definition as a body in orbit around the Sun that was large enough to have achieved hydrostatic equilibrium and to have cleared the neighbourhood around its orbit.^[5] The practical meaning of "cleared the neighborhood" is that a planet is comparatively massive enough for its gravitation to control the orbits of all objects in its vicinity. By the IAU's definition, there are eight planets in the Solar System; four terrestrial planets (Mercury, Venus, Earth and Mars) and four giant planets, which can be divided further into two gas giants (Jupiter and Saturn) and two ice giants (Uranus and Neptune). When excluding the Sun, the four giant planets account for more than 99 percent of the mass of the Solar System.

		*Mercury^[6]	*Venus^[7]	*Earth^[8]	*Mars^[9]	°Jupiter^[10]	°Saturn^[11]	†Uranus^[12]	†Neptune^[13]

Astronomical symbol^[q]
Mean distance from the Sun	km AU	57,909,175 0.38709893	108,208,930 0.72333199	149,597,890 1.00000011	227,936,640 1.52366231	778,412,010 5.20336301	1,426,725,400 9.53707032	2,870,972,200 19.19126393	4,498,252,900 30.06896348
Equatorial radius	km :E^[f]	2,439.64 0.3825	6,051.59 0.9488	6,378.1 1	3,397.00 0.53260	71,492.68 11.209	60,267.14 9.449	25,557.25 4.007	24,766.36 3.883
Surface area	km² :E^[f]	75,000,000 0.1471	460,000,000 0.9020	510,000,000 1	140,000,000 0.2745	64,000,000,000 125.5	44,000,000,000 86.27	8,100,000,000 15.88	7,700,000,000 15.10
Volume	km³ :E^[f]	6.083×10¹⁰ 0.056	9.28×10¹¹ 0.857	1.083×10¹² 1	1.6318×10¹¹ 0.151	1.431×10¹⁵ 1,321.3	8.27×10¹⁴ 763.62	6.834×10¹³ 63.102	6.254×10¹³ 57.747
Mass	kg :E^[f]	3.302×10²³ 0.055	4.8690×10²⁴ 0.815	5.972×10²⁴ 1	6.4191×10²³ 0.107	1.8987×10²⁷ 318	5.6851×10²⁶ 95	8.6849×10²⁵ 14.5	1.0244×10²⁶ 17
Gravitational parameter	m^3/s²	2.203×10¹³	3.249×10¹⁴	3.986×10¹⁴	4.283×10¹³	1.267×10¹⁷	3.793×10¹⁶	5.794×10¹⁵	6.837×10¹⁵
Density	g/cm³	5.43	5.24	5.52	3.940	1.33	0.70	1.30	1.76
Equatorial gravity	m/s²	3.70	8.87	9.81	3.71	23.12	10.44	8.69	11.00
Escape velocity	km/s	4.25	10.36	11.18	5.02	59.54	35.49	21.29	23.71
Rotation period^[g]	days	58.646225	243.0187	0.99726968	1.02595675	0.41354	0.44401	0.71833	0.67125
Orbital period^[g]	years	0.2408467	0.61519726	1.0000174	1.8808476	11.862615	29.447498	84.016846	164.79132
Mean orbital speed	km/s	47.8725	35.0214	29.7859	24.1309	13.0697	9.6724	6.8352	5.4778
Eccentricity		0.20563069	0.00677323	0.01671022	0.09341233	0.04839266	0.05415060	0.04716771	0.00858587
Inclination^[f]	deg.	7.00	3.39	0^[8]	1.85	1.31	2.48	0.76	1.77
Axial tilt^[i]	deg.	0.0	177.3^[h]	23.44	25.19	3.12	26.73	97.86^[h]	28.32
Mean surface temperature	K	440–100	730	287	227	152 ^[j]	134 ^[j]	76 ^[j]	73 ^[j]
Mean air temperature^[k]	K			288		165	135	76	73
Atmospheric composition		He, Na⁺ P⁺	CO₂, N₂, SO₂	N₂, O₂, Ar, CO₂	CO₂, N₂ Ar	H₂, He	H₂, He	H₂, He CH₄	H₂, He CH₄
Number of known moons^[v]		0	0	1	2	79	62	27	14
Rings?		No	No	No	No	Yes	Yes	Yes	Yes
Planetary discriminant^[l]^[o]		9.1×10⁴	1.35×10⁶	1.7×10⁶	1.8×10⁵	6.25×10⁵	1.9×10⁵	2.9×10⁴	2.4×10⁴

Dwarf planets

Key
^† asteroid	^‡ plutoid

The IAU, the internationally recognized authority for assigning designations to celestial bodies, defines dwarf planets as bodies that are large enough to have achieved hydrostatic equilibrium, but have not cleared their neighbourhoods of similar objects. Since 2008, there have been five dwarf planets recognized by the IAU. Ceres orbits in the asteroid belt, between the orbits of Mars and Jupiter. The others orbit beyond Neptune and are subclassified as plutoids.

		^†Ceres^[14]	^‡Pluto^[15]	^‡Haumea^[16]	^‡Makemake^[17]	^‡Eris^[18]

Astronomical symbol^[q]
Minor planet number		1	134340	136108	136472	136199
Mean distance from the Sun	km AU	413,700,000 2.766	5,906,380,000 39.482	6,484,000,000 43.335	6,850,000,000 45.792	10,210,000,000 67.668
Mean radius	km :E^[f]	473 0.0742	1,190^[19] 0.186	816 (1161×852×569) 0.13^[20]^[21]	715±7 0.11^[22]	1,163 0.18^[23]
Volume	km³ :E^[f]	4.21×10⁸ 0.00039^[b]	6.99×10⁹ 0.0065	1.5×10⁹ 0.001	1.5×10⁹ 0.001^[b]	6.59×10⁹ 0.0061^[b]
Surface area	km² :E^[f]	2,770,000 0.0054^[a]	17,700,000 0.035	6,800,000 0.0133^[z]	6,400,000 0.013^[a]	17,000,000 0.0333^[a]
Mass	kg :E^[f]	9.39×10²⁰ 0.00016	1.305×10²² 0.0022	4.01 ± 0.04×10²¹ 0.0007^[24]	< 4.4 ×10²¹ < 0.0007	1.7×10²² 0.0028^[25]
Gravitational parameter	m^3/s²	6.263 × 10¹⁰	8.710 × 10¹¹	2.674 × 10¹¹	< 2.9366 × 10¹¹	1.108 × 10¹²
Density	g/cm³	2.16	1.87	2.6^[20]	< 2.933	2.25^[c]
Equatorial gravity	m/s²	0.27^[d]	0.62	0.63^[d]	< 0.57	~0.8^[d]
Escape velocity	km/s^[e]	0.51	1.21	0.91	< 0.91	1.37
Rotation period^[g]	days	0.3781	6.38723	0.167	0.3238	1.0792
Orbital period^[g]	years	4.599	247.92065	285.4	309.9	557
Mean orbital speed	km/s	17.882	4.7490	4.484^[o]	4.4^[o]	3.436^[n]
Eccentricity		0.080	0.24880766	0.18874	0.159	0.44177
Inclination^[f]	deg.	10.587	17.14175	28.19	28.96	44.187
Axial tilt^[i]	deg.	4	119.59^[h]	?	?	?
Mean surface temperature^[w]	K	167^[26]	40^[27]	<50^[28]	30	30
Atmospheric composition		H₂O	N₂, CH_4, CO	?	N₂, CH₄^[29]	N₂, CH₄^[30]
Number of known moons^[v]		0	5	2^[31]	1^[32]	1^[33]
Planetary discriminant^[l]^[o]		0.33	0.077	0.023	0.02	0.10

Most-likely additional dwarf planets

These trans-Neptunian objects are theoretically large enough to be dwarf planets. Dozens more could have been included.^[34] Both Quaoar and Orcus have known moons that have allowed the mass of the systems to be determined. Both are more massive than the 5×10²⁰ kg recommendation of the IAU 2006 draft proposal as sufficient for classification as a dwarf planet.^[35]
However, it is possible that dark, low-density objects like Salacia retain internal porosity from their formation and are not planetary bodies.^[36] In this case, only 2007 OR₁₀, Quaoar, Orcus and Sedna are likely dwarf-planet candidates.

		Orcus^[37]	Ixion^[38]	2002 MS₄^[39]	Salacia^[40]	Varuna^[41]	2005 UQ₅₁₃^[42]	Quaoar^[43]	2007 OR₁₀^[44]	Gǃkúnǁ’hòmdímà^[45]	Sedna^[46]

Minor-planet number		90482	28978	307261	120347	20000	202421	50000	225088	229762	90377
Semi-major axis	km AU	5,896,946,000 39.419	5,935,999,000 39.68	6,273,000,000 41.93	6,311,000,000 42.19	6,451,398,000 43.13	6,479,089,380 43.31	6,493,296,000 43.6	10,072,433,340 67.33	11,032,000,000 73.74	78,668,000,000 525.86
Mean radius^[s]	km :E^[f]	473 0.0742	402 0.063	467^[47] 0.073	427^[48] 0.067	~350 0.055	460 0.072^[aa]	422 0.066	~640 0.10	440 0.07^[aa]	~500 0.08
Surface area^[a]	km² :E^[f]	2,811,000 0.0055	2,031,000 0.00398	2,741,000 0.00537	2,291,000 0.00449	1,091,000 0.00214	2,659,000 0.0052	2,238,000 0.00439	6,160,000 0.012	2,430,000 0.005	3,000,000 0.006
Volume^[b]	km³ :E^[f]	443,000,000 0.0004	272,000,000 0.0003	427,000,000 0.0004	327,000,000 0.0003	549,000,000 0.0005	408,000,000 0.0004	315,000,000 0.0003	1,440,000,000 0.001	360,000,000 0.0003	500,000,000 0.0005
Mass^[t]	kg :E^[f]	6.32×10²⁰^[49] 0.0001	?	?	4.5×10²⁰^[50] 0.000075	5.5×10²⁰ 0.00009	?	(1.3–1.9)×10²¹^[51] 0.0003	1.75×10²¹ 0.0003	?	?
Density^[t]	g/cm³	1.5±0.3^[49]	?	?	1.16^[50]	0.9992^[52]	?	>2.8^[51]	1.76	?	?
Equatorial gravity^[d]	m/s²	0.27	?	?	0.11	0.14	?	0.24	0.285	?	?
Escape velocity^[e]	km/s	0.50	?	?	0.43	0.38	?	0.45	0.604	?	?
Rotation period^[g]	days	0.5495	0.51667	?	0.25	0.13216^[52]	0.29292	0.7366	1.86708	0.46	0.42^[53]
Orbital period^[g]	years	247.492	249.95	271.53	274.03	283.20	285.12	287.97	552.52	633.28	12,059.06
Mean orbital speed	km/s	4.68	4.66	4.58	4.58	4.53	4.52	4.52	3.63	3.25	1.04
Eccentricity		0.22552	0.242	0.148	0.10312	0.051	0.145	0.038	0.5	0.490	0.855
Inclination^[f]	deg.	22.5	19.6	17.693	23.9396	17.2	25.69	8	30.7	23.37	11.93
Mean surface temperature^[w]	K	~42	~43	~43	?	~43	~41	~41	~30	~32	~12
Number of known moons		1^[54]	0	0	1	0	0	1^[55]	1	1^[56]	0
Planetary discriminant^[l]^[o]		0.003	0.0027	<0.1	<0.1	0.0027	0.003	0.0015	<0.1	0.036^[x]	?^[x]
Absolute magnitude (H)		2.30	3.20	3.7	4.2	3.70	3.40	2.71	1.7	3.40	1.58

Satellites

Key
^🜨 Satellite of Earth	^♃ Satellite of Jupiter	^♄ Satellite of Saturn	^⛢ Satellite of Uranus	^♆ Satellite of Neptune	^♇ Satellite of Pluto

There are 19 natural satellites in the Solar System that are known to be massive enough to be close to hydrostatic equilibrium. Alan Stern calls these satellite planets, although the term major moon is more common.

Several of these were once in equilibrium but are no longer: these include all of the moons listed for Saturn apart from Titan and Rhea. Other moons that were once in equilibrium but are no longer very round, such as Saturn's Phoebe, are not included. Satellites are listed first in order from the Sun, and second in order from their parent body.

		^🜨Moon^[57]	^♃Io^[58]	^♃Europa^[59]	^♃Ganymede^[60]	^♃Callisto^[61]	^♄Mimas^[p]	^♄Enceladus^[p]	^♄Tethys^[p]	^♄Dione^[p]	^♄Rhea^[p]

Astronomical symbol^[q]
Mean distance from primary:	km	384,399	421,600	670,900	1,070,400	1,882,700	185,520	237,948	294,619	377,396	527,108
Mean radius	km :E^[f]	1,737.1 0.272	1,815 0.285	1,569 0.246	2,634.1 0.413	2,410.3 0.378	198.30 0.031	252.1 0.04	533 0.084	561.7 0.088	764.3 0.12
Surface area^[a]	km² :E^[f]	37,930,000 0.074	41,910,000 0.082	30,900,000 0.061	87,000,000 0.171	73,000,000 0.143	490,000 0.001	799,000 0.0016	3,570,000 0.007	3,965,000 0.0078	7,337,000 0.0144
Volume^[b]	km³ :E^[f]	2.2×10¹⁰ 0.02	2.53×10¹⁰ 0.02	1.59×10¹⁰ 0.015	7.6×10¹⁰ 0.07	5.9×10¹⁰ 0.05	3.3×10⁷ 0.00003	6.7×10⁷ 0.00006	6.3×10⁸ 0.0006	7.4×10⁸ 0.0007	1.9 ×10⁹ 0.0018
Mass	kg :E^[f]	7.3477×10²² 0.0123	8.94×10²² 0.015	4.80×10²² 0.008	1.4819×10²³ 0.025	1.0758×10²³ 0.018	3.75×10¹⁹ 0.000006	1.08×10²⁰ 0.000018	6.174×10²⁰ 0.00010	1.095×10²¹ 0.00018	2.306×10²¹ 0.0004
Density^[c]	g/cm³	3.3464	3.528	3.01	1.936	1.83	1.15	1.61	0.98	1.48	1.23
Equatorial gravity^[d]	m/s²	1.622	1.796	1.314	1.428	1.235	0.0636	0.111	0.145	0.231	0.264
Escape velocity^[e]	km/s	2.38	2.56	2.025	2.741	2.440	0.159	0.239	0.393	0.510	0.635
Rotation period	days^[g]	27.321582 (sync)^[m]	1.7691378 (sync)	3.551181 (sync)	7.154553 (sync)	16.68902 (sync)	0.942422 (sync)	1.370218 (sync)	1.887802 (sync)	2.736915 (sync)	4.518212 (sync)
Orbital period about primary	days^[g]	27.32158	1.769138	3.551181	7.154553	16.68902	0.942422	1.370218	1.887802	2.736915	4.518212
Mean orbital speed^[o]	km/s	1.022	17.34	13.740	10.880	8.204	14.32	12.63	11.35	10.03	8.48
Eccentricity		0.0549	0.0041	0.009	0.0013	0.0074	0.0202	0.0047	0.02	0.002	0.001
Inclination to primary's equator	deg.	18.29–28.58	0.04	0.47	1.85	0.2	1.51	0.02	1.51	0.019	0.345
Axial tilt^[i]^[u]	deg.	6.68	0	0	0–0.33^[62]	0	0	0	0	0	0
Mean surface temperature^[w]	K	220	130	102	110^[63]	134	64	75	64	87	76
Atmospheric composition		Ar, He Na, K, H	SO₂^[64]	O₂^[65]	O₂^[66]	O₂, CO₂^[67]		H₂O, N₂ CO₂, CH₄^[68]
Rings?		No	No	No	No	No	No	No	No	No	Yes?

		^♄Titan^[p]	^♄Iapetus^[p]	^⛢Miranda^[r]	^⛢Ariel^[r]	^⛢Umbriel^[r]	^⛢Titania^[r]	^⛢Oberon^[r]	^♆Triton^[69]	^♇Charon^[15]

Mean distance from primary:	km	1,221,870	3,560,820	129,390	190,900	266,000	436,300	583,519	354,759	17,536
Mean radius	km :E^[f]	2,576 0.404	735.60 0.115	235.8 0.037	578.9 0.091	584.7 0.092	788.9 0.124	761.4 0.119	1353.4 0.212	603.5 0.095
Surface area^[a]	km² :E^[f]	83,000,000 0.163	6,700,000 0.013	700,000 0.0014	4,211,300 0.008	4,296,000 0.008	7,820,000 0.015	7,285,000 0.014	23,018,000 0.045	4,580,000 0.009
Volume^[b]	km³ :E^[f]	7.16×10¹⁰ 0.066	1.67×10⁹ 0.0015	5.5×10⁷ 0.00005	8.1×10⁸ 0.0007	8.4×10⁸ 0.0008	2.06×10⁹ 0.0019	1.85×10⁹ 0.0017	1×10¹⁰ 0.00923	9.2×10⁸ 0.00085
Mass	kg :E^[f]	1.3452×10²³ 0.023	1.8053×10²¹ 0.0003	6.59×10¹⁹ 0.00001	1.35×10²¹ 0.00023	1.2×10²¹ 0.0002	3.5×10²¹ 0.0006	3.014×10²¹ 0.00051	2.14×10²² 0.00358	1.52×10²¹ 0.00025
Density^[c]	g/cm³	1.88	1.08	1.20	1.67	1.40	1.72	1.63	2.061	1.65
Equatorial gravity^[d]	m/s²	1.35	0.22	0.08	0.27	0.23	0.39	0.35	0.78	0.28
Escape velocity^[e]	km/s	2.64	0.57	0.19	0.56	0.52	0.77	0.73	1.46	0.58
Rotation period	days^[g]	15.945 (sync)^[m]	79.322 (sync)	1.414 (sync)	2.52 (sync)	4.144 (sync)	8.706 (sync)	13.46 (sync)	5.877 (sync)	6.387 (sync)
Orbital period about primary	days	15.945	79.322	1.4135	2.520	4.144	8.706	13.46	5.877	6.387
Mean orbital speed^[o]	km/s	5.57	3.265	6.657	5.50898	4.66797	3.644	3.152	4.39	0.2
Eccentricity		0.0288	0.0286	0.0013	0.0012	0.005	0.0011	0.0014	0.00002	0.0022
Inclination to primary's equator	deg.	0.33	14.72	4.22	0.31	0.36	0.14	0.10	157^[h]	0.001
Axial tilt^[i]^[u]	deg.	0	0	0	0	0	0	0	0	?
Mean surface temperature^[w]	K	93.7^[70]	130	59	58	61	60	61	38^[71]	53
Atmospheric composition		N₂, CH₄^[72]							N₂, CH₄^[73]

Notes

.mw-parser-output .refbegin{font-size:90%;margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{list-style-type:none;margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li,.mw-parser-output .refbegin-hanging-indents>dl>dd{margin-left:0;padding-left:3.2em;text-indent:-3.2em;list-style:none}.mw-parser-output .refbegin-100{font-size:100%}

Unless otherwise cited:^[ac]

^{^} The planetary discriminant for the planets is taken from material published by Stephen Soter.^[74] Planetary discriminants for Ceres, Pluto and Eris taken from Soter, 2006. Planetary discriminants of all other bodies calculated from the Kuiper belt mass estimate given by Lorenzo Iorio.^[75]

^{^} Saturn satellite info taken from NASA Saturnian Satellite Fact Sheet.^[76]

^{^} Astronomical symbols for all listed objects except Ceres taken from NASA Solar System Exploration.^[77] Symbol for Ceres was taken from material published by James L. Hilton.^[78] The Moon is the only natural satellite with an astronomical symbol, and Pluto and Ceres the only dwarf planets.

^{^} Uranus satellite info taken from NASA Uranian Satellite Fact Sheet.^[79]

^{^} Radii for plutoid candidates taken from material published by John A. Stansberry et al.^[23]

^{^} Axial tilts for most satellites assumed to be zero in accordance with the Explanatory Supplement to the Astronomical Almanac: "In the absence of other information, the axis of rotation is assumed to be normal to the mean orbital plane."^[80]

^{^} Natural satellite numbers taken from material published by Scott S. Sheppard.^[81]

Manual calculations (unless otherwise cited)

^{^} Surface area A derived from the radius using ${begin{smallmatrix}A=4pi r^{2}end{smallmatrix}}$ , assuming sphericity.

^{^} Volume V derived from the radius using ${begin{smallmatrix}V={frac {4}{3}}pi r^{3}end{smallmatrix}}$ , assuming sphericity.

^{^} Density derived from the mass divided by the volume.

^{^} Surface gravity derived from the mass m, the gravitational constant G and the radius r: G*m/r².

^{^} Escape velocity derived from the mass m, the gravitational constant G and the radius r: sqrt((2*G*m)/r) .

^{^} Orbital speed is calculated using the mean orbital radius and the orbital period, assuming a circular orbit.

^{^} Assuming a density of 2.0

^{^} Calculated using the formula ${begin{smallmatrix}T = {frac {T_{{{textrm {eff}}}}(1-qp_{{nu }})^{{1/4}}}{{sqrt {2}}}}{sqrt {52/r}},end{smallmatrix}}$ where T_eff =54.8 K at 52 AU, $p_{{nu }}$ is the geometric albedo, q=0.8 is the phase integral, and $r$ is the distance from the Sun in AU. This formula is a simplified version of that in section 2.2 of Stansberry et al., 2007,^[23] where emissivity and beaming parameter were assumed equal unity, and $pi$ was replaced with 4 accounting for the difference between circle and sphere. All parameters mentioned above were taken from the same paper.

^{^} Calculated using the formula ${begin{smallmatrix}D={frac {1329}{{sqrt {p}}}}10^{{-0.2H}}end{smallmatrix}}$ , where H is the absolute magnitude, p is the geometric albedo and D is the diameter in km, and assuming an albedo of 0.15, as per Dan Bruton.^[82]

^{^} Mass derived from the density multipied by the volume.

Individual calculations

^{^} Derived from density

^{^} Surface area was calculated using the formula for a scalene ellipsoid:

${begin{smallmatrix}2pi left(c^{2}+b{sqrt {a^{2}-c^{2}}}E(alpha ,m)+{frac {bc^{2}}{{sqrt {a^{2}-c^{2}}}}}F(alpha ,m)right),,!end{smallmatrix}}$ where ${begin{smallmatrix}alpha =arccos left({frac {c}{a}}right),,!end{smallmatrix}}$ is the modular angle, or angular eccentricity; ${begin{smallmatrix}m={frac {b^{2}-c^{2}}{b^{2}sin(alpha )^{2}}},!end{smallmatrix}}$ and ${begin{smallmatrix}F(alpha ,m),!end{smallmatrix}}$ , ${begin{smallmatrix}E(alpha ,m),!end{smallmatrix}}$ are the incomplete elliptic integrals of the first and second kind, respectively. The values 980 km, 759 km, and 498 km were used for a, b, and c respectively.

Other notes

^{^} Relative to Earth

^{^} Sidereal

^{^} Retrograde

^{^} The inclination of the body's equator from its orbit.

^{^} At pressure of 1 bar

^{^} At sea level

^{^} The ratio between the mass of the object and those in its immediate neighborhood. Used to distinguish between a planet and a dwarf planet.

^{^} This object's rotation is synchronous with its orbital period, meaning that it only ever shows one face to its primary.

^{^} Objects' planetary discriminants based on their similar orbits to Eris. Sedna's population is currently too little-known for a planetary discriminant to be determined.

^{^} Proteus average diameter: 210 km;^[69] Mimas average diameter: 199 km^[76]

^{^} "Unless otherwise cited" means that the information contained in the citation is applicable to an entire line or column of a chart, unless another citation specifically notes otherwise.

References

^ Woolfson, Michael Mark (2000). "The Origin and Evolution of the Solar System". Astronomy & Geophysics. 41 (1): 1.12–1.19. Bibcode:2000A&G....41a..12W. doi:10.1046/j.1468-4004.2000.00012.x..mw-parser-output cite.citation{font-style:inherit}.mw-parser-output .citation q{quotes:"""""""'""'"}.mw-parser-output .citation .cs1-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Lock-green.svg/9px-Lock-green.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Lock-gray-alt-2.svg/9px-Lock-gray-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .citation .cs1-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Lock-red-alt-2.svg/9px-Lock-red-alt-2.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Wikisource-logo.svg/12px-Wikisource-logo.svg.png")no-repeat;background-position:right .1em center}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-maint{display:none;color:#33aa33;margin-left:0.3em}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}

^ NASA Solar System exploration Sun factsheet Archived 2008-01-02 at the Wayback Machine and NASA Sun factsheet Archived 2010-07-15 at the Wayback Machine NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ ^a^b Leong, Stacy (2002). Elert, Glenn, ed. "Period of the Sun's Orbit around the Galaxy (Cosmic Year)". The Physics Factbook (self-published). Retrieved 2008-06-26.

^ Aschwanden, Markus J. (2007). "The Sun". In McFadden, Lucy Ann; Weissman, Paul R.; Johnsson, Torrence V. Encyclopedia of the Solar System. Academic Press. p. 80.

^ "IAU 2006 General Assembly: Result of the IAU Resolution votes" (Press release). International Astronomical Union (News Release – IAU0603). 2006-08-24. Retrieved 2007-12-31. (orig link Archived 2007-01-03 at the Wayback Machine)

^ NASA Mercury Fact Sheet Archived 2015-11-06 at the Wayback Machine and NASA Solar System Exploration Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ NASA Venus Factsheet Archived 2016-03-10 at WebCite and NASA Solar System Exploration Factsheet Archived 2006-09-29 at the Wayback Machine NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ ^a^b
NASA Earth factsheet and NASA Solar System Exploration Factsheet Archived 2009-08-27 at the Wayback Machine Archived 2009-08-27 at the Wayback Machine NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ NASA Mars Factsheet Archived 2010-06-12 at the Wayback Machine and NASA Mars Solar System Exploration Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^
NASA Jupiter factsheet Archived 2011-10-05 at WebCite Archived 2011-10-05 at WebCite and NASA Solar System Exploration Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^
NASA Saturn factsheet Archived 2011-08-21 at WebCite Archived 2011-08-21 at WebCite and NASA Solar System Exploration Saturn Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ NASA Uranus factsheet Archived 2011-08-11 at WebCite and NASA Solar System Exploration Uranus Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ NASA Neptune factsheet and NASA Solar System Exploration Neptune Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ "NASA Asteroid Factsheet". NASA. Archived from the original on 2010-01-18. Retrieved 2008-11-17.

^ ^a^b NASA Pluto factsheet and NASA Solar System Exploration Pluto Factsheet Retrieved on 2008-11-17 (unless otherwise cited)

^ (i) Lockwood, Alexandra C.; Brown, Michael (Mike) E.; Stansberry, John A. (2014). "The Size and Shape of the Oblong Dwarf Planet Haumea". Earth, Moon, and Planets. 111 (3–4): 127–137. arXiv:1402.4456. Bibcode:2014EM&P..111..127L. doi:10.1007/s11038-014-9430-1.

(ii) Rabinowitz, David L.; Barkume, Kristina M.; Brown, Michael (Mike) E.; et al. (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. arXiv:astro-ph/0509401. Bibcode:2006ApJ...639.1238R. doi:10.1086/499575.

(iii) "Jet Propulsion Laboratory Small-Body Database Browser: 136108 Haumea". NASA's Jet Propulsion Laboratory (2008-05-10 last obs). Retrieved 2008-11-13. (unless otherwise cited)

^ (i) Buie, Marc W. (2008-04-05). "Orbit Fit and Astrometric record for 136472". SwRI (Space Science Department). Retrieved 2008-07-13.

(ii) "NASA Small Bodies Database Browser: 136472 Makemake (2005 FY₉)". NASA JPL. Retrieved 2008-10-03. (unless otherwise cited)

^ "NASA Small Body Database Browser: Eris". NASA JPL. Retrieved 2008-11-13. (unless otherwise cited)

^ https://www.youtube.com/watch?v=dWr29KIs2Ns NASA. 24 July 2015. Event occurs at 52:30. Retrieved 30 July 2015. We had an uncertainty that ranged over maybe 70 kilometers, we've collapsed that to plus and minus two, and it's centered around 1186

^ ^a^b Lockwood, Alexandra C.; Brown, Michael (Mike) E.; Stansberry, John A. (2014). "The Size and Shape of the Oblong Dwarf Planet Haumea". Earth, Moon, and Planets. 111 (3–4): 127–137. arXiv:1402.4456. Bibcode:2014EM&P..111..127L. doi:10.1007/s11038-014-9430-1.

^ Lellouch, Emmanuel; Kiss, Csaba; Santos-Sanz, Pablo; et al. (2010). ""TNOs are cool": A survey of the trans-Neptunian region II. The thermal lightcurve of (136108) Haumea". Astronomy and Astrophysics. 518: L147. arXiv:1006.0095. Bibcode:2010A&A...518L.147L. doi:10.1051/0004-6361/201014648.

^ Brown, Michael (Mike) E. (2013). "On the size, shape, and density of dwarf planet Makemake". The Astrophysical Journal. 767: L7. arXiv:1304.1041. doi:10.1088/2041-8205/767/1/L7.

^ ^a^b^c Stansberry, John A.; Grundy, Will M.; Brown, Michael (Mike) E.; et al. (2007). "Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope". The Solar System Beyond Neptune: 161. arXiv:astro-ph/0702538. Bibcode:2008ssbn.book..161S.

^ Brown, Michael (Mike) E.; Bouchez, Antonin H.; Rabinowitz, David L.; et al. (October 2005). "Keck Observatory laser guide star adaptive optics discovery and characterization of a satellite to large Kuiper belt object 2003 EL₆₁". The Astrophysical Journal Letters. 632 (L45): L45. Bibcode:2005ApJ...632L..45B. doi:10.1086/497641.

^ Brown, Michael (Mike) E.; Schaller, Emily L. (15 June 2007). "The Mass of Dwarf Planet Eris". Science. 316 (5831): 1585. Bibcode:2007Sci...316.1585B. doi:10.1126/science.1139415. PMID 17569855.

^ Saint-Pé, Olivier; Combes, Michel; Rigaut, François J. (1993). "Ceres surface properties by high-resolution imaging from Earth". Icarus. 105 (2): 271–281. Bibcode:1993Icar..105..271S. doi:10.1006/icar.1993.1125.

^ Than, Ker (2006). "Astronomers: Pluto colder than expected". Space.com (via CNN.com). Retrieved on 2006-03-05.

^ Trujillo, Chadwick A.; Brown, Michael (Mike) E.; Barkume, Kristina M.; et al. (February 2007). "The Surface of 2003 EL₆₁ in the Near Infrared". The Astrophysical Journal. 655 (2): 1172–1178. arXiv:astro-ph/0601618. Bibcode:2007ApJ...655.1172T. doi:10.1086/509861.

^ Brown, Michael (Mike) E.; Barkume, Kristina M.; Blake, Geoffrey A.; et al. (2007). "Methane and Ethane on the Bright Kuiper Belt Object 2005 FY₉". The Astronomical Journal. 133 (1): 284–289. Bibcode:2007AJ....133..284B. doi:10.1086/509734.

^ Licandro, Javier; Grundy, Will M.; Pinilla-Alonso, Noemi; de Leon, Jerome P. (2006). "Visible spectroscopy of 2003 UB₃₁₃: evidence for N₂ ice on the surface of the largest TNO?" (PDF). Astronomy and Astrophysics. 458 (1): L5–L8. arXiv:astro-ph/0608044. Bibcode:2006A&A...458L...5L. CiteSeerX 10.1.1.257.1298. doi:10.1051/0004-6361:20066028.

^ Ragozzine, Darin; Brown, Michael (Mike) E.; Trujillo, Chadwick A.; Schaller, Emily L. "Orbits and Masses of the 2003 EL₆₁ Satellite System". AAS DPS conference 2008. Archived from the original on 2013-07-18. Retrieved 2008-10-17.

^ Chang, Kenneth (26 April 2016). "Makemake, the Moonless Dwarf Planet, Has a Moon, After All". New York Times. Retrieved 26 April 2016.

^ Brown, Michael (Mike) E.; van Dam, Marcos A.; Bouchez, Antonin H.; et al. (2006). "Satellites of the largest Kuiper belt objects". The Astrophysical Journal. 639 (1): L43–L46. arXiv:astro-ph/0510029. Bibcode:2006ApJ...639L..43B. doi:10.1086/501524.

^ Brown, Michael (Mike) E. "The Dwarf Planets". Caltech. Retrieved 2008-09-25.

^ Gingerich, Owen (2006-08-16). "The Path to Defining Planets" (PDF). Harvard-Smithsonian Center for Astrophysics and IAU EC Planet Definition Committee chair. 3. p. 4. Retrieved 2007-03-13.

^ W.M. Grundy, K.S. Noll, M.W. Buie, S.D. Benecchi, D. Ragozzine & H.G. Roe, 'The Mutual Orbit, Mass, and Density of Transneptunian Binary Gǃkúnǁ’hòmdímà ((229762) 2007 UK₁₂₆)', Icarus (forthcoming)

^ "JPL Small-Body Database Browser: 90482 Orcus (2004 DW)" (2008-02-10 last obs). NASA JPL. Retrieved 2008-07-02. (unless otherwise cited)

^ "JPL Small-Body Database Browser: 28978 Ixion (2001 KX₇₆)" (2007-07-12 last obs). NASA JPL. Retrieved 2008-10-04. (unless otherwise cited)

^ "JPL Small-Body Database Browser: 307261 (2002 MS₄)" (2009-09-19 last obs). Retrieved 2013-12-23. (unless otherwise cited)

^ "JPL Small-Body Database Browser: 120347 Salacia" (2010-11-05 last obs). Retrieved 2013-12-23. (unless otherwise cited)

^ "JPL Small-Body Database Browser: 20000 Varuna (2000 WR₁₀₆)" (2007-11-17 last obs). NASA JPL. Retrieved 2008-07-02. (unless otherwise cited)

^ "JPL Small-Body Database Browser: (2005 UQ₅₁₃)" (2008-11-29 last obs). Retrieved 2008-07-31.(unless otherwise cited)

^ "NASA JPL Database Browser: 50000 Quaoar". NASA JPL. Retrieved 2008-12-19. (unless otherwise cited)

^ "NASA Small Bodies Database Browser: 2007 OR₁₀". NASA JPL. Retrieved 2008-12-20. (unless otherwise cited)

^ "JPL Small-Body Database Browser: 229762 (2007 UK₁₂₆)" (2009-12-20 last obs). Retrieved 2010-05-02. (unless otherwise cited)

^ Buie, Marc W. (2007-08-13). "Orbit Fit and Astrometric record for 90377". Deep Ecliptic Survey. Retrieved 2006-01-17. (unless otherwise cited)

^ Vilenius, Esa; Kiss, Csaba; Mommert, Michael; et al. (April 4, 2012). ""TNOs are Cool": A survey of the trans-Neptunian region VI. Herschel/PACS observations and thermal modeling of 19 classical Kuiper belt objects". Astronomy & Astrophysics. 541: A94. arXiv:1204.0697. Bibcode:2012A&A...541A..94V. doi:10.1051/0004-6361/201118743.

^ Fornasier, Sonia; Lellouch, Emmanuel; Müller, Thomas G.; et al. (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". Astronomy & Astrophysics. 555: A15. arXiv:1305.0449v2. doi:10.1051/0004-6361/201321329.

^ ^a^b Brown, Michael (Mike) E.; Ragozzine, Darin; Stansberry, John A.; Fraser, Wesley C. (2009). "The size, density, and formation of the Orcus-Vanth system in the Kuiper belt". Astronomical Journal. 139 (6): 2700. arXiv:0910.4784. Bibcode:2010AJ....139.2700B. doi:10.1088/0004-6256/139/6/2700.

^ ^a^b Stansberry, John A. (2012). "Physical Properties of Trans-Neptunian Binaries (120347) Salacia–Actaea and (42355) Typhon–Echidna". Icarus. 219 (2): 676–688. Bibcode:2012Icar..219..676S. doi:10.1016/j.icarus.2012.03.029.

^ ^a^b Brown, Michael (Mike) E.; Fraser, Wesley C. (2009). Quaoar: A Rock in the Kuiper Belt. DPS meeting #41. American Astronomical Society. Bibcode:2009DPS....41.6503F.
(Backup reference)

^ ^a^b Jewitt, David C. & Sheppard, Scott S. (2002). "Physical Properties of Trans-Neptunian Object (20000) Varuna". The Astronomical Journal. 123 (4): 2110–2120. arXiv:astro-ph/0201082. Bibcode:2002AJ....123.2110J. doi:10.1086/339557. Retrieved on 2008-12-19.

^ "Case of Sedna's Missing Moon Solved". Harvard Smithsonian Center for Astrophysics. 2005. Retrieved 2011-07-05.

^ Distant EKO The Kuiper Belt Electronic newsletter, March 2007 Retrieved on 2008-11-17

^ "IAUC 8812: Sats OF 2003 AZ_84, (50000), (55637), (90482); V1281 Sco; V1280 Sco". International Astronomical Union. Retrieved 2011-07-05.

^ (229762) 2007 UK₁₂₆, Johnston's Archive. Last updated 20 September 2011

^ NASA Moon factsheet and NASA Solar System Exploration Moon Factsheet NASA Retrieved on 2008-11-17 (unless otherwise cited)

^ "NASA Io Factsheet". NASA. Retrieved 2008-11-16. (unless otherwise cited)

^ "NASA Europa Factsheet". NASA. Retrieved 2008-11-16. (unless otherwise cited)

^ "NASA Ganymede Factsheet". NASA. Retrieved 2008-11-16. (unless otherwise cited)

^ "NASA Callisto Factsheet". NASA. Retrieved 2008-11-16.

^ Bills, Bruce G. (2005). "Free and forced obliquities of the Galilean satellites of Jupiter". Icarus. 175 (1): 233–247. Bibcode:2005Icar..175..233B. doi:10.1016/j.icarus.2004.10.028.

^ Orton, Glenn S.; Spencer, John R.; Travis, Larry D.; et al. (1996). "Galileo Photopolarimeter-radiometer observations of Jupiter and the Galilean Satellites". Science. 274 (5286): 389–391. Bibcode:1996Sci...274..389O. doi:10.1126/science.274.5286.389.

^ Pearl, John C.; Hanel, Rudolf A.; Kunde, Virgil G.; et al. (1979). "Identification of gaseous SO₂ and new upper limits for other gases on Io". Nature. 288 (5725): 755. Bibcode:1979Natur.280..755P. doi:10.1038/280755a0.

^ Hall, Doyle T.; et al.; Detection of an oxygen atmosphere on Jupiter's moon Europa, Nature, Vol. 373, 1995, pp. 677–679 (accessed 2006-15-04)

^ Hall, Doyle T.; Feldman, Paul D.; McGrath, Melissa A.; Strobel, Darrell F. (1998). "The Far-Ultraviolet Oxygen Airglow of Europa and Ganymede". The Astrophysical Journal. 499 (1): 475–481. Bibcode:1998ApJ...499..475H. doi:10.1086/305604. Retrieved on 2008-11-17.

^ Liang, Mao-Chang; Lane, Benjamin F.; Pappalardo, Robert T.; et al. (2005). "Atmosphere of Callisto" (PDF). Journal of Geophysical Research. 110 (E02003): E02003. Bibcode:2005JGRE..11002003L. doi:10.1029/2004JE002322. Archived from the original (PDF) on 2009-02-25. Retrieved on 2008-11-17.

^ Waite, J. Hunter, Jr.; Combi, Michael R.; Ip, Wing-Huen; et al. (2006). "Cassini Ion and Neutral Mass Spectrometer: Enceladus Plume Composition and Structure". Science. 311 (5766): 1419–1422. Bibcode:2006Sci...311.1419W. doi:10.1126/science.1121290. PMID 16527970. Retrieved on 2008-11-17.

^ ^a^b Triton info taken from NASA Neptunian Satellite Fact Sheet Archived 2011-10-05 at WebCite NASA Retrieved on 2009-01-18 (unless otherwise cited)

^ Hasenkopf, Christa A.; Beaver, Melinda R.; Tolbert, Margaret A.; et al. (2007). "Optical Properties of Titan Haze Laboratory Analogs Using Cavity Ring Down Spectroscopy" (PDF). Workshop on Planetary Atmospheres (1376): 51. Bibcode:2007plat.work...51H. Archived from the original (PDF) on 2014-05-26. Retrieved 2007-10-16.

^ Tryka, Kimberly; Brown, Robert H.; Anicich, Vincent; et al. (August 1993). "Spectroscopic Determination of the Phase Composition and Temperature of Nitrogen Ice on Triton". Science. 261 (5122): 751–754. Bibcode:1993Sci...261..751T. doi:10.1126/science.261.5122.751. PMID 17757214.

^ Niemann, Hasso B.; Atreya, Sushil K.; Bauer, Sven J.; et al. (2005). "The abundances of constituents of Titan's atmosphere from the GCMS instrument on the Huygens probe". Nature. 438 (7069): 779–784. Bibcode:2005Natur.438..779N. doi:10.1038/nature04122. PMID 16319830.

^ Broadfoot, A. Lyle; Atreya, Sushil K.; Bertaux, Jean-Loup; et al. (1989-12-15). "Ultraviolet Spectrometer Observations of Neptune and Triton". Science. 246 (4936): 1459–1466. Bibcode:1989Sci...246.1459B. doi:10.1126/science.246.4936.1459. PMID 17756000.

^ Soter, Stephen (2006-08-16). "What is a Planet?". The Astronomical Journal. 132 (6): 2513–2519. arXiv:astro-ph/0608359. Bibcode:2006AJ....132.2513S. doi:10.1086/508861.

^ Iorio, Lorenzo (March 2007). "Dynamical determination of the mass of the Kuiper Belt from motions of the inner planets of the Solar system". Monthly Notices of the Royal Astronomical Society. 375 (4): 1311–1314. arXiv:gr-qc/0609023. Bibcode:2007MNRAS.375.1311I. doi:10.1111/j.1365-2966.2006.11384.x.

^ ^a^b NASA Saturnian Satellite Fact Sheet NASA Retrieved on 2008-11-17

^ "NASA Solar System Exploration: Planet Symbols". NASA. Retrieved 2009-01-26.

^ Hilton, James L. "When did asteroids become minor planets?" (PDF). U.S. Naval Observatory. Retrieved 2008-10-25.

^ "NASA Uranian Satellite Fact Sheet". NASA. Archived from the original on 2010-01-18. Retrieved 2008-11-17.

^ Seidelmann, P. Kenneth, ed. (1992). Explanatory Supplement to the Astronomical Almanac. University Science Books. p. 384.

^ Sheppard, Scott S. "The Jupiter Satellite Page". Carnegie Institution for Science, Department of Terrestrial Magnetism. Retrieved 2008-04-02.

^ Bruton, Dan. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics & Astronomy (Stephen F. Austin State University). Archived from the original on 2010-03-23. Retrieved 2009-01-20.

搜尋此網誌

Agfdhyk

List of gravitationally rounded objects of the Solar System

Contents

Sun

Planets