universal time coordinate
31Longitude — For Dava Sobel s book about John Harrison, see Longitude (book). For the adaptation of Sobel s book, see Longitude (TV series). Map of Earth Longitude (λ) Lines of longitude appear vertical with varying curvature in this projection, but are… …
32Spacetime — For other uses of this term, see Spacetime (disambiguation). Two dimensional analogy of spacetime distortion. Matter changes the geometry of spacetime, this (curved) geometry being interpreted as gravity. White lines do not represent the… …
33Minkowski diagram — In the theory of relativity each observer assigns the event at A to a different time and location. The Minkowski diagram was developed in 1908 by Hermann Minkowski and provides an illustration of the properties of space and time in the special… …
34Declination — For other uses, see Declination (disambiguation). In astronomy, declination (abbrev. dec or δ) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. Declination in astronomy is… …
35Day — For other uses, see Day (disambiguation). Water, Rabbit, and Deer: three of the 20 day symbols in the Aztec calendar, from the Aztec calendar stone. A day is a unit of time, commonly defined as an interval equal to 24 hours …
36General relativity — For a generally accessible and less technical introduction to the topic, see Introduction to general relativity. General relativity Introduction Mathematical formulation Resources …
37UTC offset — The UTC offset is the time offset from Coordinated Universal Time (UTC). It is mostly given as hour or hour and minute. Many time zones employ two time offsets, one for standard time and one for daylight saving time. Before the introduction of… …
38Metric tensor — In the mathematical field of differential geometry, a metric tensor is a type of function defined on a manifold (such as a surface in space) which takes as input a pair of tangent vectors v and w and produces a real number (scalar) g(v,w) in a… …
39ΔT — This article is about the time difference. For the temperature difference, see psychrometrics. ΔT vs. time from 1657 to 1984[1] ΔT, Delta T, delta T, deltaT, or DT is the time difference obtained by subtracting Universal Time (UT) from… …
40Global Positioning System — GPS redirects here. For other uses, see GPS (disambiguation). Geodesy Fundamentals …
