Yards to Light-years (yd to ly)
1 yard equals 9.665215626×10⁻¹⁷ light-years (rounded).
How to convert yards to light-years
To convert yards to light-years, multiply the number of yards by 9.665215626×10⁻¹⁷. The factor is rounded to 10 significant digits. To go the other way, multiply light-years by 1.034638066×10¹⁶ (rounded).
light-years = yards × 9.665215626×10⁻¹⁷
Example: 10 yards = 9.665215626×10⁻¹⁶ light-years.
About these units
Yard (yd)
3 feet or 36 inches, exactly 0.9144 meters. Used for sports fields, fabric and short distances in the US and UK.
Yard descends from the Old English gerd or gyrd, meaning a branch, stave or measuring rod. It first appears in the late seventh-century laws of Ine of Wessex, though there it names a tax unit, the yardland. Around 959 to 963 King Edgar ordered that the measure held at Winchester be used throughout his realm, the earliest record of a prototype. A story that Henry I fixed the yard as the distance from his nose to his thumb is later folklore, and the true origin, whether pace, cubit or waist, remains speculative.
Britain defined the Imperial Standard Yard in 1824 as the distance between two marks on a brass rod at 62 degrees Fahrenheit. A fire in 1834 damaged the standard, a replacement was made in 1845, and the Weights and Measures Act 1855 recognized it. The 1959 international agreement then fixed the yard at exactly 0.9144 meter. Today it measures American and Canadian football fields, association football pitches and cricket pitches, appears on UK road signs for short distances, and is still used to sell fabric in the US and UK.
1 yard = 0.9144 meters (exactly).
Sources: Wikipedia: Yard; Wikipedia: Inch; NIST Guide to the SI, Appendix B.8: conversion factors
Light-year (ly)
The distance light travels in one Julian year: exactly 9,460,730,472,580,800 meters (about 9.46 trillion km).
Despite the name, a light-year measures distance rather than time, and its coinage is a little later than most people assume. Friedrich Bessel measured the distance to the star 61 Cygni in 1838 but did not use the unit himself. The light-year appeared in print in 1851, in a German article by Otto Ule, who explained its odd use of a time word by comparing it to saying that a place is an hour's walk away.
The International Astronomical Union defines it as the distance light travels in a vacuum in one Julian year of 365.25 days, about 9.46 trillion kilometers. NIST lists it as 9.460 73 times 10 to the 15th meters. Light-years dominate popular science, while professional astronomers mostly prefer the parsec, about 3.26 light-years. For scale, Proxima Centauri, the nearest star to the Sun, is about 4.24 light-years away, and the Milky Way is roughly 100,000 light-years across.
1 light-year = 9.460730473×10¹⁵ meters (approximately).
Sources: Wikipedia: Light-year; NIST Guide to the SI, Appendix B.8: conversion factors
Related conversions
- Light-years to yards (reverse)
- Yards to meters
- Yards to kilometers
- Yards to centimeters
- Yards to millimeters
- Yards to inches
- Yards to feet
- Yards to miles
- Yards to micrometers
- Yards to nanometers
- Yards to nautical miles
- Yards to pixels (CSS)
- Yards to picometers
- Meters to light-years
- Kilometers to light-years
- Centimeters to light-years
- Millimeters to light-years
- Inches to light-years
- Feet to light-years
- Miles to light-years
- Micrometers to light-years
- Nanometers to light-years
- Nautical miles to light-years
- Pixels (CSS) to light-years
See all length units.