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This is a list of numbered minor planets in the Solar System, in numerical order. there are 452,298 numbered minor planets, and 246,182 unnumbered.〔(【引用サイトリンク】 publisher=Minor Planet Center )〕 Most are not particularly noteworthy; only 19,513 minor planets have been given names〔 (the first nameless minor planet being number 3708).〔(【引用サイトリンク】 publisher=Minor Planet Center )〕 Five minor planets have been accepted as dwarf planets by the IAU, and hundreds more are likely to be dwarf planets. The following are lists of minor planets by physical properties, orbital properties, or discovery circumstances: * Asteroids and dwarf planets * * List of unnumbered minor planets – minor planets yet to receive a numbered designation (about 35% of minor planets as of November 2015) * * List of trans-Neptunian objects – objects whose orbit carries it beyond that of Neptune * * List of possible dwarf planets – minor planets suspected to be massive enough to pull themselves into a sphere. * * List of dwarf planets – Pluto, Ceres, Eris, Haumea, and Makemake * * List of exceptional asteroids – for example, asteroids with a highly inclined orbit, particularly large, fast or slowly rotating * * List of minor planets and comets visited by spacecraft – any minor planet or comet at one point observed or passed close to by a spacecraft * * Minor-planet moon – any astronomical body that orbits a minor planet as its natural satellite *Comets * * List of numbered comets – comets observed through multiple orbits around the Sun. * * List of periodic comets – comets with orbital periods shorter than 200 years * * List of hyperbolic comets – comets from the Oort cloud with enough orbital energy to escape the Sun's gravity == Numbering and naming conventions == After discovery, asteroids generally receive a provisional designation (such as "1989 AC"), then a sequential number (such as 4179), and finally (optionally) a name (such as "Toutatis"), in that order. In modern times, an asteroid receives a sequential number only after it has been observed several times over at least 4 oppositions. Asteroids whose orbits are not (yet) precisely known are known by their provisional designation. This rule was not necessarily followed in earlier times, and some asteroids received a number but became subsequently lost asteroid . All of these have now been recovered; the last "lost" numbered asteroid was 719 Albert. Only after a number is assigned is the asteroid eligible to receive a name. Usually the discoverer has up to 10 years to pick a name; some asteroids remain unnamed. Especially towards the end of the twentieth century, with large-scale automated asteroid discovery programs such as LINEAR, the pace of discoveries has increased so much that it seems likely that the vast majority of minor planets will never receive names. For the reasons mentioned above, the sequence of numbers only approximately matches the timeline of discovery. In extreme cases, such as lost asteroids, there may be a considerable mismatch: for instance the high-numbered 69230 Hermes was originally discovered in 1937, but it was a lost until 2003. Only after it was rediscovered could its orbit be established and a number assigned. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「List of minor planets」の詳細全文を読む スポンサード リンク
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