Light-day

A Light-day or lightday is a unit of measurement of length.

• It is an astrographic scale measurement.
• It is a standard Imperial metric.

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Please refer to the following AAB Library Data for more information:
Starship:

• Speed of Travel
  • Light Speed (c)
  • FTL
  • NAFAL (STL)
  • Astronomical Unit (AU)
  • Light-second (ls)
  • Light-minute (lm)
  • Light-hour (lh)
  • Light-day (ld)
  • Light-week (lw)
  • Light-year (ly)
  • Parsec (pc)

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Description (Specifications)

A light-day is specifically the distance light travels in a vacuum over a period of one day.

• The common abbreviation is ld.

One (Imperial) light-day is equal to:

1. About 2.590×10¹⁰ kilometers
2. About 173.1456 astronomical units
3. About 8.39428×10^-4 parsecs

It is based on the standard Imperial day of 24 hours.

Following the Solomani Rim War, the Imperium began to move away from Terranocentric metrics, instead adopting a set of universal scales and measures not specifically based on the physical parameters of the primary star system of an enemy state.

One (Solomani) light-day is equal to:

1. About 2.590x10¹⁰ kilometers
2. About 173.1456 astronomical units
3. About 8.39428×10^-4 parsecs

It is based on the Terran day of 24 hours.

History & Background (Dossier)

• The exact length of the light-day depends on the length of the reference day used in the calculation.
• The light-day is often used to measure distances between worlds within systems, especially in reference to distance relative to communication and/or sensor lag.
• The preferred unit of general measurement for such distances is the astronomical unit (AU).

References & Contributors (Sources)

This page uses content from Wikipedia. The original article was at Light-second#Use_in_astronomy. The list of authors can be seen in the page history. The text of Wikipedia is available under the Commons Attribution-ShareAlike 3.0 Unported License.

This list of sources was used by the Traveller Wiki Editorial Team and individual contributors to compose this article. Copyrighted material is used under license from Mongoose Publishing or by permission of the author. The page history lists all of the contributions.

• Wikipedia Table - Lightday
• Contributor: WHULorigan