Question

write a note on light year​

Answer 1

Answer:

A light-year is a unit of distance. It is the distance that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 trillion km

Answer 2

Answer:

Explanation:

The light-year is a unit of length used to express astronomical distances and measures about 9.46 trillion kilometres (9.46 x 1012 km) or 5.88 trillion miles (5.88 x 1012 mi).[note 1] As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days).[2] Because it includes the word "year", the term light-year may be misinterpreted as a unit of time.[3]

The light-year is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist and popular science publications.[3] The unit most commonly used in professional astrometry is the parsec (symbol: pc, about 3.26 light-years; the distance at which one astronomical unit subtends an angle of one second of arc).