Memory Alpha
Register
Advertisement
Memory Alpha

One light year (abbr. l.y.) is the distance that light travels in one Earth year. It is approximately equal to 9.46 e12×1012 kilometers, or 5.88 e12×1012 miles.

Light years are common units of measurement used in starship navigation. (TNG: "The Naked Now")

When Commander Benjamin Sisko welcomed the first guest from the Gamma Quadrant in the Alpha Quadrant, a Tosk, he told him that he traveled almost ninety thousand light years through the wormhole. (DS9: "Captive Pursuit")

In 2369, a Vanoben transport was raided two light years away from Deep Space 9. (DS9: "Vortex")

The same year, Sisko told Kai Opaka that the Gamma Quadrant is seventy thousand light years away from Bajor. (DS9: "Battle Lines")

Related links

Background

The exact length of a light year depends on the exact length used for one "Earth year". The IAU uses a Julian year of 365.25 days, while other sources may use a Gregorian year of 365.2425 days, or another year altogether.

Source year (days) light year (kilometers) light year (miles)
IAU 365.25 9,460,730,472,581 5,878,625,373,184
Gregorian 365.2425 9,460,536,207,068 5,878,504,662,190
Google 365.242199 9.460 528 4 e12×1012 5.878 499 81 e12×1012
Yahoo 365.2411 9.460 5 e12×1012 5,878,482,164,161

Note that while Yahoo separately reports a year length of 365.24220 days, its rounding of the light year length to five digits works out to a year length of ~365.2411 days.

External link

Advertisement