What is 690em in Light Years?

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What is 690 Ems (690em) in Light Years (ly)?

What is 690em in ly? Convert 690 Ems (690em) to Light Years (ly) and show formula, brief history on the units and quick maths for the conversion.

Enter Ems to convert to Light Years


Quick Reference for Converting Ems to Light Years

Formula
ly = em / 2.2353212201403E+18
Quick Rough Maths
To get the Light Years, divide the number of Ems by 2235321.2 trillion
Ems (em) in 1 Light Year
There are 2.2353212201403E+18 Ems in 1 Light Year
Light Years (ly) in 1 Em
There are 0 Light Years in 1 Em

Unit Information

Em
/ɛm/
Symbol: em
Unit System: Typography

What is the Em?

The em is a unit of length in the field of typography and uses the symbol em.

It is a "relative" unit and equals the currently specified point size. For example, 1 em in a 24-point typeface is equal to 24 points. This allows a typographer to specify text size relative to a base figure.

In metal type, the em was equal to the line height of the metal body. This meant the physical size of the letter could not exceed the em. In digital type, the em is a grid of arbitrary resolution so can be scaled to any point size for screen or print.

Light Year
/lʌɪt jɪə,jəː/
Symbol: ly
Unit System: Astronomical System of Units

What is the Light Year?

The light year is a unit of length in the Astronomical system of units. It uses the symbol ly.

Often confused with a unit of time as it contains the word "year", it is actually defined by the International Astronomical Union (IAU) as the amount of distance that light travels in a vacuum in one Julian year (365.25 days).

Using the speed of light (299,792,458 m/s or 'c') and the Julian year (as apposed to the Gregorian year which is 365.2425 days), we can equivalate 1 light year as 9,460,730,472,580,800 metres or ≈ 9.46 trillion kilometres.


Conversion Tables for Ems (em) to Light Years (ly)