请输入您要查询的英文单词:

 

单词 sidereal day
释义

sidereal day


sidereal day

n. The time required for a single rotation of the earth on its axis in reference to any star or to the vernal equinox at the meridian, equal to 23 hours, 56 minutes, 4.09 seconds in units of mean solar time.

sidereal day

n (Astronomy) See day5

side′real day′



n. the interval between two successive passages of the vernal equinox over the meridian, being about four minutes shorter than a mean solar day. [1785–95]

sidereal day

A measure of time approximately equal to 23 hr, 56 min, 4.09 sec. A sidereal day represents the time needed for one complete rotation of the Earth on its axis.
Thesaurus
Noun1.sidereal day - the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar daydaytime unit, unit of time - a unit for measuring time periodssidereal time - measured by the diurnal motion of stars

sidereal day


sidereal day:

see sidereal timesidereal time
(ST), time measured relative to the fixed stars; thus, the sidereal day is the period during which the earth completes one rotation on its axis so that some chosen star appears twice on the observer's celestial meridian.
..... Click the link for more information.
.

sidereal day

The interval between two successive passages of a catalog equinox across a given meridian. It is divided into 24 sidereal hours. The sidereal day is 3 minutes 56 seconds shorter than the mean solar day.

Sidereal day

(religion, spiritualism, and occult)

A sidereal day is the period of time it takes for Earth to complete one rotation on its axis with respect to a fixed point in space. Specifically, a sidereal day begins and ends when the local meridian for any given location on Earth passes through 0° Aries (the vernal point). Because of the motion of Earth around the Sun, sidereal days are slightly shorter than ordinary solar days. A sidereal day is 23 hours 56 minutes and 4.09 seconds in length; a sidereal hour is ½4 the length of a sidereal day.

sidereal day

[sī′dir·ē·əl ′dā] (astronomy) The time between two successive upper transits of the vernal equinox; this period measures one sidereal day.

sidereal day

sidereal dayThe period between two successive transits of a particular meridian on the earth by the first point of Aries or successive transits of the vernal equinox. Because the first point of Aries is not fixed in space and it precesses along the equinoctial 11.26” of ecliptic by arc each year, the sidereal day measured relative to Aries is minutely shorter than that measured relative to a fixed point in space. These two days are known as practical and theoretical sidereal days, respectively. The time over the upper branch of any meridian is equal to 24 h of mean sidereal time or 23 h 56 min 4.09054 s of mean solar time.

sidereal day

Slightly less than the 24 hours of a solar day (23 hours, 56 minutes, 4.1 seconds). Used in astronomy, sidereal means "when a star crosses the meridian" (the meridian is an imaginary circle around the earth). For example, at noon, the sun and stars are overhead, but 23 hours, 56 minutes and 4.1 seconds later, the earth is back in relation to the stars, but not the sun, which takes approximately four minutes longer.
AcronymsSeeSD

sidereal day


Related to sidereal day: synodic month
  • noun

Synonyms for sidereal day

noun the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day

Synonyms

  • day

Related Words

  • time unit
  • unit of time
  • sidereal time
随便看

 

英语词典包含2567994条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
更新时间:2025/2/1 7:52:58