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(Units should be in kilometers, not meters, since km's are SI counterparts to imperial miles. Meters are SI counterparts to imperial feet.)
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One '''light year''' is the distance that [[light]] travels in one [[Earth]] [[year]]. It is approximately equal to 9.46 {{exp|15}} [[meter]]s, or 5.88 {{exp|12}} [[mile]]s.
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One '''light year''' is the distance that [[light]] travels in one [[Earth]] [[year]]. It is approximately equal to 9.46 {{exp|12}} [[kilometer]]s, or 5.88 {{exp|12}} [[mile]]s.
   
 
Light years are common units of measurement used in [[starship]] navigation.
 
Light years are common units of measurement used in [[starship]] navigation.
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! Source
 
! Source
 
! year (days)
 
! year (days)
! light year (meters)
+
! light year (kilometers)
 
! light year (miles)
 
! light year (miles)
 
|-
 
|-
 
| IAU || 365.25
 
| IAU || 365.25
| 9,460,730,472,580,800
+
| 9,460,730,472,581
 
| 5,878,625,373,184
 
| 5,878,625,373,184
 
|-
 
|-
 
| Gregorian || 365.2425
 
| Gregorian || 365.2425
| 9,460,536,207,068,020
+
| 9,460,536,207,068
 
| 5,878,504,662,190
 
| 5,878,504,662,190
 
|-
 
|-
 
| Google || 365.242199
 
| Google || 365.242199
| 9.460 528 4 {{exp|15}}
+
| 9.460 528 4 {{exp|12}}
 
| 5.878 499 81 {{exp|12}}
 
| 5.878 499 81 {{exp|12}}
 
|-
 
|-
 
| Yahoo || 365.2411<sup>&Dagger;</sup>
 
| Yahoo || 365.2411<sup>&Dagger;</sup>
| 9.460 5 {{exp|15}}
+
| 9.460 5 {{exp|12}}
 
| 5,878,482,164,161
 
| 5,878,482,164,161
 
|}
 
|}

Revision as of 05:20, 10 July 2010

One light year 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.

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