Convert astronomical units to light-years

Explanation

From this page you can convert astronomical units to light-years (or au to ly) simply, by using the application above.

In case you are wondering, to convert from astronomical units to light-years you need to multiply by 0.00001581. This factor is calculated using the respective definitions of the two units you can find below.

Formula

1 au≈0.00001581 ly

astronomical unitsau

dimension	length
symbol	au

The astronomical unit (au) is a unit of length used in astronomy.

One astronomical unit is roughly equal to the distance between Earth and the Sun.

The unit is used to measure distances at the scale of solar systems. For example, Jupiter is approximately 5 au from the Sun.

Definition of the astronomical unit

The astronomical unit is defined as exactly 149597870700 meters.

International Astronomical Union

Equivalences

One astronomical unit is approximately equal to:

Some Facts

If the Sun were to be erased from reality, we would realise it 8 minutes and 20 seconds later, it is the time that light and gravity from the Sun take to reach us. During all that time, the Earth would continue on its orbit around an empty part of space as if nothing happened.

light-yearsly

dimension	length
symbol	ly

The light-year (ly) is a unit of length.

It is used to measure astronomical distances like the one between stars or the size of galaxies in popular science publications. It is superseded by the parsec in scientific contexts.

Definition of the light-year

A light-year is the distance that light travels in vacuum in one julian year (i.e. 365.25 days of 86400 seconds each).

Value in terms of the SI

One light-year is equivalent to 9460730472580800 meters.

Equivalences

One light-year is also equivalent to:

Some Facts

After the Sun, Proxima Centauri is the nearest star. Nearest and yet extremely far away, 4.244 light-years (25 trillion miles) from Earth. We have to agree that in a first approximation, the universe is almost empty. And yet, here we are, converting things to light-years.

astronomical unit	au
parsec	pc
kiloparsec	kpc
megaparsec	Mpc
gigaparsec	Gpc

light-nanosecond	lns	0.000 000 001
light-microsecond	lµs	0.000 001
light-millisecond	lms	0.001
light-second	ls	1
light-minute	lmin	60
light-hour	lh	3600
light-day	ld	86 400
light-year	ly	31 557 600
kilolight-year	kly	31 557 600 000
megalight-year	Mly	31 557 600 000 000
gigalight-year	Gly	31 557 600 000 000 000