翻訳と辞書 Words near each other ・ Light-front quantization applications ・ Light-gas gun ・ Light-gated ion channel ・ Light-harvesting complex ・ Light-harvesting complexes of green plants ・ Light-Hearted Isabel ・ Light-in-flight imaging ・ Light-independent reactions ・ Light-induced voltage alteration ・ Light-Life ・ Light-mantled albatross ・ Light-on-dark color scheme ・ Light-Oxygen-Voltage-sensing domain ・ Light-second ・ Light-sport aircraft ・ Light-time correction ・ Light-vented bulbul ・ Light-weight Combat Vehicle System ・ Light-Weight Identity ・ Light-weight process ・ Light-winged lesser house bat ・ Light-year ・ Lightbank ・ Lightbeam (software) ・ LightBike ・ Lightbody ・ Lightbot ・ Lightbournus ・ Lightbournus russjenseni ・ Lightbown Aspinall Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Light-time correction ： ウィキペディア英語版 Light-time correction Light-time correction is a displacement in the ''apparent position'' of a celestial object from its ''true position'' (or ''geometric position'') caused by the object's motion during the time it takes its light to reach an observer. Light-time correction occurs in principle during the observation of any moving object, because the speed of light is finite. The magnitude and direction of the displacement in position depends upon the distance of the object from the observer and the motion of the object, and is measured at the instant at which the object's light reaches the observer. It is ''independent'' of the motion of the observer. It should be contrasted with the aberration of light, which depends upon the instantaneous velocity of the observer at the time of observation, and is independent of the motion or distance of the object. Light-time correction can be applied to any object whose distance and motion are known. In particular, it is usually necessary to apply it to the motion of a planet or other Solar System object. For this reason, the combined displacement of the apparent position due to the effects of light-time correction and aberration is known as ''planetary aberration''. By convention, light-time correction is not applied to the positions of stars, because their motion and distance may not be known accurately. ==Calculation== A calculation of light-time correction usually involves an iterative process. An approximate light-time is calculated by dividing the object's geometric distance from Earth by the speed of light. Then the object's velocity is multiplied by this approximate light-time to determine its approximate displacement through space during that time. Its previous position is used to calculate a more precise light-time. This process is repeated as necessary. For planetary motions, a few (3–5) iterations are sufficient to match the accuracy of the underlying ephemerides. 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「Light-time correction」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.