HOW LONG WOULD IT TAKE TO REACH THESE , IF WE TRAVEL IN THE SPEED OF LIGHT ? 👇🏼

An image of the Andromeda galaxy, as seen by NASA's GALEX observatory. Credit: NASA/JPL-Caltech

The LIGHT- YEAR is a unit of length used to express astronomical distances and measure about 9.46 trillion kilometres ( 3,00,000 x 60 x 60 x 24 x 365 = 9.46 x 10¹² km ) or 5.88 trillion miles ( 5.88 x 10¹² mi )

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).”

How many light years away ?

Earth is approximately …..

•     8.3 light-minutes from the sun
•     4.3 light-years away from proxima Centauri, our closest neighbouring star
•     320 light-years from the North star, Polaris
•     26000 light-years away from the centre of our galaxy , milky-way
•     2.5 million light-years from Andromeda , our closest neighbouring galaxy.
•     13.4 billion light-years away from one of the oldest galaxies ever found , called GN-z11

Why use light years?

Measuring in light-years allows astronomers to determine how far back in time they are viewing .Because light takes time to travel to our eyes ,everything we view in the night sky has already happened . In otherwords ,when you observe something 1 light years away , you see it appeared exactly one years ago.

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HOW LONG WOULD IT TAKE TO REACH THESE , IF WE TRAVEL IN THE SPEED OF LIGHT ? 👇🏼

https://pvgspace.blogspot.com/2020/02/how-long-would-it-take-to-reach-these.html

source : Wikipedia