Why is the galaxy measured in light years rather than kilometers or miles?

Answer 1

Mostly because of the sheer number of digits it would take to write down the numbers in Kilometers or miles. A light year is 9,460,730,472,580.8 km or 5,878,630,000,000 miles.

What is simpler, writing 236,518,261,814,520 kilometers or simply 25 light years?

Also the speed of light is generally accepted as a constant speed, and precise way of measuring distance. (The question of why it ISN'T actually constant is a whole other issuer)

Answer 2

The distances in kilometers or meters are very big numbers; the distance to Toliman is about 4.3 light-years, each light-year is about 9,500,000,000,000 kilometers. A light-year gives smaller numbers - it also tells how long it will take to travel to Toliman, at the fastest-possible speed (it seems the speed of light is the speed limit in the Universe). However, astronomers also like to use another unit: the parsec.

The distances in kilometers or meters are very big numbers; the distance to Toliman is about 4.3 light-years, each light-year is about 9,500,000,000,000 kilometers. A light-year gives smaller numbers - it also tells how long it will take to travel to Toliman, at the fastest-possible speed (it seems the speed of light is the speed limit in the Universe). However, astronomers also like to use another unit: the parsec.

The distances in kilometers or meters are very big numbers; the distance to Toliman is about 4.3 light-years, each light-year is about 9,500,000,000,000 kilometers. A light-year gives smaller numbers - it also tells how long it will take to travel to Toliman, at the fastest-possible speed (it seems the speed of light is the speed limit in the Universe). However, astronomers also like to use another unit: the parsec.

The distances in kilometers or meters are very big numbers; the distance to Toliman is about 4.3 light-years, each light-year is about 9,500,000,000,000 kilometers. A light-year gives smaller numbers - it also tells how long it will take to travel to Toliman, at the fastest-possible speed (it seems the speed of light is the speed limit in the Universe). However, astronomers also like to use another unit: the parsec.

Answer 3

We use the appropriate measure for every type of measurement. For example, we use feet or meters to measure distances around the house, and we use kilometers or miles to measure distances around town. For distances off the Earth, we use Astronomical Units to measure the distances between planets, and light years to measure the distances between stars. That's because the distance to the various stars are all so enormously far away that the numbers would need to be huge, and we'd lose our ability to make easy comparisons.

Answer 4

The distances in kilometers or meters are very big numbers; the distance to Toliman is about 4.3 light-years, each light-year is about 9,500,000,000,000 kilometers. A light-year gives smaller numbers - it also tells how long it will take to travel to Toliman, at the fastest-possible speed (it seems the speed of light is the speed limit in the Universe). However, astronomers also like to use another unit: the parsec.

Answer 5

Galaxies are measured in light years because they are incredibly vast, and light years are more useful for expressing these immense distances. A light year is the distance light travels in one year, which is a more convenient unit than kilometers or miles when dealing with astronomical scales.

Answer 6

A light-year is a measurement of how fast light can travel in one year. All other measurements are simply too small to measure interstellar distances.

Answer 7

The distances in space are much too big to be measured in kilometres, the numbers would be impractical to say and read.

Answer 8

Because a lightyear equals to just under 10 trillion kilometres :)