| Name of Planetary Body | Orbital Elements | Orbital Period (years) | Mass (ME) | Number of Known Satellites | Discovery | ||
|---|---|---|---|---|---|---|---|
| Semimajor Axis (AU) | Eccentricity | Discoverer Name | Announcement Date | ||||
| Mercury | 0.3870993 | 0.20564 | 0.2408467 | 0.05527 | 0 | ? | Prehistoric |
| Venus | 0.723336 | 0.00678 | 0.61519726 | 0.81500 | 0 | ? | Prehistoric |
| Earth | 1.000003 | 0.01671 | 1.0000174 | 1.0000 | 1 | - | - |
| Mars | 1.52371 | 0.09339 | 1.8808158 | 0.10745 | 2 | ? | Prehistoric |
| Jupiter | 5.2029 | 0.0484 | 11.862615 | 317.83 | 63 | ? | Prehistoric |
| Saturn | 9.537 | 0.0539 | 29.447498 | 95.159 | 61 | ? | Prehistoric |
| Uranus | 19.189 | 0.04726 | 84.016846 | 14.500 | 27 | W. Herschel | 1781 Mar 13 |
| Neptune | 30.0699 | 0.00859 | 164.79132 | 17.204 | 13 | J.C. Adams & U.J. LeVerrier | 1846 Sep 23 |
| Name of Planetary Body | Orbital Elements | Orbital Period (years) | Mass (ME) | Number of Known Satellites | Discovery | ||
|---|---|---|---|---|---|---|---|
| Semimajor Axis (AU) | Eccentricity | Discoverer Name | Announcement Date | ||||
| Ceres | 2.7658 | 0.078 | 4.59984 | 0.00016 | 0 | G. Piazzi | 1801 Jan 1 |
| Plutoids3 | |||||||
| Pluto | 39.4821 | 0.24883 | 248.0208 | 0.00220 | 5 | C. Tombaugh | 1930 Mar 13 |
| Haumea | 43.34 | 0.189 | 285.4 | 0.00070 | 2 | J. Ortiz, et al. | 2005 Jul 27 |
| Makemake | 45.79 | 0.159 | 309.9 | 0.0007 | 0 | M. Brown, et al. | 2005 Jul 29 |
| Eris | 67.67 | 0.44177 | 557.2 | 0.00278 | 1 | M. Brown, et al. | 2003 Oct 21 |
333273 Numbered, 17301 Named
| Asteroids | ||||
|---|---|---|---|---|
| Rocky composition with few volatiles | ||||
| Type of Asteroid | Distinguishing Orbital Characteristics | Number of Known Bodies | ||
| Atens | a <1.0 AU | Near-Earth Asteroids (NEAs): q < 1.017 AU and Q > 0.983 AU |
720 | |
| Apollos | q < 1.0 AU | 4484 | ||
| Amors | a < 1.3 AU | Mars-Crossers: q <1.617 AU and Q > 1.431 AU |
3767 | |
| Main Belt and other sub-categories | 1.78 AU < a < 3.70 AU (Main Belt: 2.1 AU < a < 3.27 AU) |
317518 | ||
| Trojans | 1:1 Resonance with a major planet; orbiting 60° ahead or behind the planet | Martian: | a = 1.524 AU | 3 |
| Jovian: | a = 5.20 AU; e < 0.15 | 5162 | ||
| Neptunian: | a = 30.17 AU; e = 0.02 | 8 | ||
| Centaurs and Scattered-Disk Objects | |
|---|---|
| Kuiper belt objects that have migrated Sunward; Some cometary features | |
| 6.8 AU < q < 41 AU; Q > 8.7 AU | 356 Known |
| Trans-Neptunian Objects | |
|---|---|
| Kuiper Belt; Source of short-period comets | |
| Some TNOs are in orbital resonance with Neptune | |
| q > 30.1 AU; Q < ~70 AU | 1251 Known |
| Oort Cloud | |
|---|---|
| Source of long-period comets | |
| q > ~70 AU; Q < ~105 AU | 4 Known |
| Comets | ||
|---|---|---|
| Icy composition; mostly frozen volatiles; sublimating volatiles form gas and dust tails when near the Sun | ||
| Type of Comet | Distinguishing Orbital Characteristics | Number of Known Bodies |
| Short-Period | P < 200 years; Small i | More than 250 (At least seven have disappeared or been destroyed) |
| Long-Period | P > 200 years, or Aperiodic; 0° < i < 180° | More than 2000 (At least 127 have disappeared or been destroyed) |
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