What is a league? – World Atlas

Objects in outer space Located at huge distances from our site Solar System. Daily units, such as miles or kilometers, become too large and complex to use when things are trillions or trillions of miles away. To simplify things, astronomers generally use it light years, which is the distance light travels over the course of one year. For example, a star Which is located 500 light years away will take 500 years to reach travel in light’s speed. There is actually another form of measurement often used in calculating vast distances: parsecs.

What is the size of a sea horse?

Proxima Centauri is the closest star to the Sun at a distance of 4.2 light years or 1.3 parsecs. Image credit: NASA/ESA

One parsec equals 3.26 light years. our nearest star, Next to CentauriIt is located 4.2 light years or 1.3 parsecs away. Going from a light year to a parsec is fairly simple, and all it takes is dividing the number of light years by 3.26. However, why does one parsec equal 3.26 light years? After all, this number seems rather specific. The parsec is calculated using parallax, a form of distance measurement used in astronomical observations. Using parallax, astronomers calculate the distance it takes one astronomical unit to meet one arcsecond. One astronomical unit is distance: after between the a land and the sun, while arcseconds are a unit of angle measurement (an arcsecond equals 1/3600 degrees). So a parsec is the calculated distance taken by an astronomical unit of distance to cover an angle of 1/3600 degrees. This distance is 3.26 light years or one parsec.

Units greater than a league

tadpole galaxy
Astronomers will generally use megafrecks or gigaparsecs to measure distances to the farthest galaxies. Image credit: NASA/ESA

To simplify larger distances, astronomers also use Kilobarsk, Megabarsk, and Gigabarsk. A kiloparsec is equal to 1,000 parsecs, and is generally used to measure distances to objects in and around Milky Way. Megaparsecs are equal to one million parsecs, and are used to measure distances to others galaxies. The largest unit, gigaparsecs, is equal to one billion parsecs and is therefore used to measure the furthest distances in space.

Units of distance in astronomy

lonliness Amount / Definition

astronomical unit

93 million miles (150 million kilometers), or the distance between the Earth and the sun

Light year

The distance light travels in one year is 5.88 trillion miles (9.46 trillion km).


The distance it takes one astronomical unit to cover an angle of one arcsecond, is 3.26 light years


1000 parsecs


million leagues


billion leagues