How many light-day in 1 ly? The answer is 365.25. We assume you are converting between light day and light year. You can view more details on each measurement unit: light-day or ly The SI base unit for length is the metre. 1 metre is equal to 3.8606955462749E-14 light-day, or 1.0570008340246E-16 ly. Note that rounding errors may occur, so always check the results. Use this page to learn how to convert between light days and light years. Type in your own numbers in the form to convert the units!
1 light-day to ly = 0.00274 ly
10 light-day to ly = 0.02738 ly
50 light-day to ly = 0.13689 ly
100 light-day to ly = 0.27379 ly
200 light-day to ly = 0.54757 ly
500 light-day to ly = 1.36893 ly
1000 light-day to ly = 2.73785 ly
You can do the reverse unit conversion from ly to light-day, or enter any two units below:
A light day (also written light-day) is a unit of length. It is defined as the distance light travels in an absolute vacuum in one day (of 86,400 seconds) or 25,902,068,371,200 metres (~26 Tm).
Note that this value is exact, since the metre is actually defined in terms of the speed of light. The light day isn't very frequently used at all since there are few astronomical objects or distances of that magnitude; the Oort cloud, for example, is thought to extend between 290 and 580 light-days out from the Sun.
A light year, abbreviated ly, is the distance light travels in one year: roughly 9.46 × 1012 kilometres (9.46 petametres, or about 5.88 × 1012 (nearly six trillion) miles). More specifically, a light year is defined as the distance that a photon would travel, in free space and infinitely far away from any gravitational or magnetic fields, in one Julian year (365.25 days of 86400 seconds each).
ConvertUnits.com provides an online conversion calculator for all types of measurement units. You can find metric conversion tables for SI units, as well as English units, currency, and other data. Type in unit symbols, abbreviations, or full names for units of length, area, mass, pressure, and other types. Examples include mm, inch, 70 kg, 150 lbs, US fluid ounce, 6'3", 10 stone 4, cubic cm, metres squared, grams, moles, feet per second, and many more!