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  2. Sidereal time - Wikipedia

    en.wikipedia.org/wiki/Sidereal_time

    Right: a few minutes later the Sun is on the local meridian again. A solar day is complete. Solar time is measured by the apparent diurnal motion of the Sun. Local noon in apparent solar time is the moment when the Sun is exactly due south or north (depending on the observer's latitude and the season). A mean solar day (what we normally measure ...

  3. Longitude by chronometer - Wikipedia

    en.wikipedia.org/wiki/Longitude_by_chronometer

    This variation must be added to or subtracted from the UTC of local apparent noon to improve the accuracy of the calculation. Using the Equation of time correction along with the time averaged ascending/descending noon sights can result in accuracies of 1 nautical mile (1.9 km) or less. Without time averaging, the difficulties in determining ...

  4. Solar time - Wikipedia

    en.wikipedia.org/wiki/Solar_time

    The apparent sun is the true sun as seen by an observer on Earth. [4] Apparent solar time or true solar time [a] is based on the apparent motion of the actual Sun. It is based on the apparent solar day, the interval between two successive returns of the Sun to the local meridian. [5] [6] Apparent solar time can be crudely measured by a sundial. [b]

  5. Noon - Wikipedia

    en.wikipedia.org/wiki/Noon

    Noon (also known as noontime or midday) is 12 o'clock in the daytime. It is written as 12 noon, 12:00 m. (for meridiem, literally 12:00 midday), 12 p.m. (for post meridiem, literally "after midday"), 12 pm, or 12:00 (using a 24-hour clock) or 1200 (military time). Solar noon is the time when the Sun appears to contact the local celestial meridian.

  6. Equation of time - Wikipedia

    en.wikipedia.org/wiki/Equation_of_time

    Animation showing equation of time and analemma path over one year.. The United States Naval Observatory states "the Equation of Time is the difference apparent solar time minus mean solar time", i.e. if the sun is ahead of the clock the sign is positive, and if the clock is ahead of the sun the sign is negative.

  7. Sunrise equation - Wikipedia

    en.wikipedia.org/wiki/Sunrise_equation

    J transit is the Julian date for the local true solar transit (or solar noon). 2451545.0 is noon of the equivalent Julian year reference. 0.0053 sin ⁡ M − 0.0069 sin ⁡ ( 2 λ ) {\displaystyle 0.0053\sin M-0.0069\sin \left(2\lambda \right)} is a simplified version of the equation of time .

  8. Wikipedia:Blank maps - Wikipedia

    en.wikipedia.org/wiki/Wikipedia:Blank_maps

    Image:Map of USA-bw.png – Black and white outlines for states, for the purposes of easy coloring of states. Image:BlankMap-USA-states.PNG – US states, grey and white style similar to Vardion's world maps. Image:Map of USA with county outlines.png – Grey and white map of USA with county outlines.

  9. Astronomical clock - Wikipedia

    en.wikipedia.org/wiki/Astronomical_clock

    The current time is indicated by a golden ball or a picture of the sun at the end of a pointer. Local noon is usually at the top of the dial, and midnight at the bottom. Minute hands are rarely used. The Sun indicator or hand gives an approximate indication of both the Sun's azimuth and altitude. For azimuth (bearing from the north), the top of ...