many people thinks that the light has an unlimited speed, however, the light have, in the space, a measurable speed, it's about 300,000 km/s or 186,411 mi/s
Do you know that in a single second light crosses a space equal to eight times the circumference of the earth? in three seconds light can reach the moon, and in eight minutes can get to the sun.
Light occupies a real interval of time, however small, in reaching the eye; and so we see objects not as they are in the moment we perceive them, but as they were the smallest fraction of a second before that.
Despite the great velocity of the light, the universe is so huge, so big, that it takes so much for the light, to bring us the "information" till our home, the earth. According to astronomers, the light takes more than fifty minutes to travel to Jupiter. Now imagine how much the light takes to reach a planet out of our solar system?
From the nearest stars, light takes fully three years in travelling to the earth. The more our observation has gone, it will take more time-light to reach us. We have been watching the universe, since our planet was formed.
