apparent solar time
91Apparent Day — A solar day; an interval between successive transits of the sun s center across an observer s meridian; the time thus measured is not equal to clock time …
92Solar Noon — The time of the day, at a specific location, when the sun reaches its highest, apparent point in the sky; equal to true or due, geographic south …
93Sidereal time — is a measure of the position of the Earth in its rotation around its axis, or time measured by the apparent diurnal motion of the vernal equinox, which is very close to, but not identical to, the motion of stars. They differ by the precession of… …
94Coordinated Universal Time — UTC redirects here. For other uses, see UTC (disambiguation). Coordinated Universal Time (abbreviated UTC) is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich… …
95Daylight saving time — This article is about daylight saving time in general. For DST in a specific location, see Daylight saving time by country. Summer time and DST redirect here. For other uses, see Summer time (disambiguation) and DST (disambiguation) …
96sidereal time — Astron. time measured by the diurnal motion of stars. A sidereal day is about four minutes shorter than a solar day, with hours, minutes, and seconds all proportionally shorter. [1805 15] * * * ▪ astronomy time as measured by the apparent… …
97Mean solar day — Day Day (d[=a]), n. [OE. day, dai, dei, AS. d[ae]g; akin to OS., D., Dan., & Sw. dag, G. tag, Icel. dagr, Goth. dags; cf. Skr. dah (for dhagh ?) to burn. [root]69. Cf. {Dawn}.] 1. The time of light, or interval between one night and the next; the …
98Alaska Time Zone — The Alaska Time Zone observes standard time by subtracting nine hours from Coordinated Universal Time (UTC 9). During daylight saving time its time offset is only eight hours (UTC 8). The clock time in this zone is based on the mean solar time of …
99Local mean time — is a form of solar time that corrects the variations of local apparent time, forming a uniform time scale at a specific longitude. Its uniformity depends only on the accuracy of the clocks used to measure it.Local mean time was used from the… …
100Dynamical time scale — has two distinct meanings and usages, both related to astronomy: In one use, which occurs in stellar physics, the dynamical time scale is alternatively known as the freefall time scale, and is in general, the length of time over which changes in… …
