Did You Know How Unimaginably Long 1 Light-year Is? – News18

A light-year is the unit of length which is used to express the astronomical distances between the stars and other celestial objects in the universe. It is a standard measuring unit for scientists to calculate distances on the galactic scale. This knowledge is available to all but most people are still unaware about the significance of this measuring unit and why it is used for astronomical space only. This curiosity led them to the public interactive platform Quora, where they posted their query which was answered by a few of its users. Ligh-year is also called Prakashvarsh in Hindi.

The light-year is not a simple measuring unit like kilometres and metres. It carries a much higher distance in its one unit. There are innumerable stars present in the universe but they are not at equal distances. Most of the stars form a group which is popularly known as a galaxy. Now, to measure the distance between the stars in a galaxy, the light-year astronomical unit is used. We often feel stars are extremely close to each other when seen from the ground but the reality is exactly opposite. One light-year is equal to the distance light travels in one year.

Light travels at a speed of 3 lakh kilometres per second. It travels around 18 million kilometres in one minute. In a year, it covers a distance of 9.46 trillion kilometres. According to scientists, if someone travels at the speed of light, then they can circle the Earth’s equator 7.5 times in one second. There are other astronomical units as well such as Parsec. 1 parsec equals 3.26 light-years. In this way, you can also measure the distance between the celestial objects in parsecs. It is estimated that there are 400 billion stars in the Milky Way galaxy. Some of these stars are at the length of one lakh light-years from each other.

Other astronomical units are also used to measure distance within a star system. Ligh-second, Light-minute, Light-hour and Light-day.