| light-year | 1 ly | 2 ly | 3 ly | 4 ly | 5 ly | 6 ly | 7 ly | 8 ly | 9 ly | 10 ly | 11 ly | 12 ly | 13 ly | 14 ly | 15 ly | 16 ly | 17 ly | 18 ly | 19 ly | 20 ly | 21 ly | 22 ly | 23 ly | 24 ly | 25 ly | 26 ly | 27 ly | 28 ly | 29 ly | 30 ly | 31 ly | 32 ly | 33 ly | 34 ly | 35 ly | 36 ly | 37 ly | 38 ly | 39 ly | 40 ly | 41 ly | 42 ly | 43 ly | 44 ly | 45 ly | 46 ly | 47 ly | 48 ly | 49 ly | 50 ly | 51 ly | 52 ly | 53 ly | 54 ly | 55 ly | 56 ly | 57 ly | 58 ly | 59 ly | 60 ly | 61 ly | 62 ly | 63 ly | 64 ly | 65 ly | 66 ly | 67 ly | 68 ly | 69 ly | 70 ly | 71 ly | 72 ly | 73 ly | 74 ly | 75 ly | 76 ly | 77 ly | 78 ly | 79 ly | 80 ly | 81 ly | 82 ly | 83 ly | 84 ly | 85 ly | 86 ly | 87 ly | 88 ly | 89 ly | 90 ly | 91 ly | 92 ly | 93 ly | 94 ly | 95 ly | 96 ly | 97 ly | 98 ly | 99 ly | 100 ly |
| inch | 3.724617482236 × 1017 in | 7.449234964472 × 1017 in | 1.1173852446708 × 1018 in | 1.4898469928944 × 1018 in | 1.862308741118 × 1018 in | 2.2347704893416 × 1018 in | 2.6072322375652 × 1018 in | 2.9796939857888 × 1018 in | 3.3521557340124 × 1018 in | 3.724617482236 × 1018 in | 4.0970792304596 × 1018 in | 4.4695409786832 × 1018 in | 4.8420027269068 × 1018 in | 5.2144644751304 × 1018 in | 5.586926223354 × 1018 in | 5.9593879715776 × 1018 in | 6.3318497198012 × 1018 in | 6.7043114680248 × 1018 in | 7.0767732162484 × 1018 in | 7.449234964472 × 1018 in | 7.8216967126956 × 1018 in | 8.1941584609192 × 1018 in | 8.5666202091428 × 1018 in | 8.9390819573664 × 1018 in | 9.31154370559 × 1018 in | 9.6840054538136 × 1018 in | 1.0056467202037 × 1019 in | 1.0428928950261 × 1019 in | 1.0801390698484 × 1019 in | 1.1173852446708 × 1019 in | 1.1546314194932 × 1019 in | 1.1918775943155 × 1019 in | 1.2291237691379 × 1019 in | 1.2663699439602 × 1019 in | 1.3036161187826 × 1019 in | 1.340862293605 × 1019 in | 1.3781084684273 × 1019 in | 1.4153546432497 × 1019 in | 1.452600818072 × 1019 in | 1.4898469928944 × 1019 in | 1.5270931677168 × 1019 in | 1.5643393425391 × 1019 in | 1.6015855173615 × 1019 in | 1.6388316921838 × 1019 in | 1.6760778670062 × 1019 in | 1.7133240418286 × 1019 in | 1.7505702166509 × 1019 in | 1.7878163914733 × 1019 in | 1.8250625662956 × 1019 in | 1.862308741118 × 1019 in | 1.8995549159404 × 1019 in | 1.9368010907627 × 1019 in | 1.9740472655851 × 1019 in | 2.0112934404074 × 1019 in | 2.0485396152298 × 1019 in | 2.0857857900522 × 1019 in | 2.1230319648745 × 1019 in | 2.1602781396969 × 1019 in | 2.1975243145192 × 1019 in | 2.2347704893416 × 1019 in | 2.272016664164 × 1019 in | 2.3092628389863 × 1019 in | 2.3465090138087 × 1019 in | 2.383755188631 × 1019 in | 2.4210013634534 × 1019 in | 2.4582475382757 × 1019 in | 2.4954937130981 × 1019 in | 2.5327398879205 × 1019 in | 2.5699860627428 × 1019 in | 2.6072322375652 × 1019 in | 2.6444784123875 × 1019 in | 2.6817245872099 × 1019 in | 2.7189707620323 × 1019 in | 2.7562169368546 × 1019 in | 2.793463111677 × 1019 in | 2.8307092864993 × 1019 in | 2.8679554613217 × 1019 in | 2.9052016361441 × 1019 in | 2.9424478109664 × 1019 in | 2.9796939857888 × 1019 in | 3.0169401606111 × 1019 in | 3.0541863354335 × 1019 in | 3.0914325102559 × 1019 in | 3.1286786850782 × 1019 in | 3.1659248599006 × 1019 in | 3.2031710347229 × 1019 in | 3.2404172095453 × 1019 in | 3.2776633843677 × 1019 in | 3.31490955919 × 1019 in | 3.3521557340124 × 1019 in | 3.3894019088347 × 1019 in | 3.4266480836571 × 1019 in | 3.4638942584795 × 1019 in | 3.5011404333018 × 1019 in | 3.5383866081242 × 1019 in | 3.5756327829465 × 1019 in | 3.6128789577689 × 1019 in | 3.6501251325913 × 1019 in | 3.6873713074136 × 1019 in | 3.724617482236 × 1019 in |
The light-year is a unit of length used to express astronomical distances. It is about 9.5 quadrillion metres or 5.9 trillion miles. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days). Because it includes the word "year", the term light-year is sometimes misinterpreted as a unit of time.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| light-year | ly | ≡ Distance light travels in vacuum in 365.25 days | = 9.4607304725808×1015 m | Science - Astronomy (Length) |
| light-years | inches | light-years | inches |
|---|---|---|---|
| 1 | = 3.724617482236E+17 | 4 | = 1.4898469928944E+18 |
| 1.5 | = 5.586926223354E+17 | 4.5 | = 1.6760778670062E+18 |
| 2 | = 7.449234964472E+17 | 5 | = 1.862308741118E+18 |
| 2.5 | = 9.31154370559E+17 | 5.5 | = 2.0485396152298E+18 |
| 3 | = 1.1173852446708E+18 | 6 | = 2.2347704893416E+18 |
The inch (abbreviation: in or ″) is a unit of length in the (British) imperial and United States customary systems of measurement now formally equal to 1⁄36 yard but usually understood as 1⁄12 of a foot. Derived from the Roman uncia ("twelfth"), inch is also sometimes used to translate related units in other measurement systems, usually understood as deriving from the width of the human thumb.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| inch | in | ≡ 2.54 cm ≡ 1⁄36 yd ≡ 1⁄12 ft | ≡ 0.0254 m | Imperial/US |
| inches | light-years | inches | light-years |
|---|---|---|---|
| 1 | = 2.6848394627619E-18 | 4 | = 1.0739357851048E-17 |
| 1.5 | = 4.0272591941428E-18 | 4.5 | = 1.2081777582429E-17 |
| 2 | = 5.3696789255238E-18 | 5 | = 1.3424197313809E-17 |
| 2.5 | = 6.7120986569047E-18 | 5.5 | = 1.476661704519E-17 |
| 3 | = 8.0545183882857E-18 | 6 | = 1.6109036776571E-17 |
| light-years | inches |
|---|---|
| 1 | = 3.724617482236 × 1017 |
| 2.6848394627619 × 10-18 | = 1 |
| Symbol | Definition |
|---|---|
| ≡ | exactly equal |
| ≈ | approximately equal to |
| = | equal to |
| digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |