"And it is We who have constructed the heaven with might, and verily, it is We who are steadily expanding it."
(The Quran, 51:47)

In 1929, Edwin Hubble made one of the greatest discoveries in the history of astronomy. While he observed the stars with a giant telescope, he found out that the light from them was shifted to the red end of the spectrum and that this shift was more pronounced the further a star was from the earth.

This discovery had an electrifying effect in the world of science, because according to the recognized rules of physics, the spectra of light beams traveling towards the point of observation tend towards violet while the spectra of the light beams moving away from the point of observation tend towards red. During Hubble's observations, the light from stars was discovered to tend towards red. This meant that they were constantly moving away from us.

Long before, Hubble made another very important discovery: Stars and galaxies moved away not only from us, but also from one another. The only conclusion that could be derived from a universe where everything moves away from everything else is that the universe constantly 'expands'.

To better understand, the universe can be thought of as the surface of a balloon being blown up. Just as the points on the surface of a balloon move apart from each other as the balloon is inflated, so do the objects in space move apart from each other as the universe keeps expanding.

Although this fact was not discovered by science until the 20th century, God has informed us of this reality in the Quran saying (what means):

"And it is We who have constructed the heaven with might, and verily, it is We who are steadily expanding it."
(The Qur'an, 51:47)

The word "heaven", as stated in this verse, is used in various places in the Qur'an with the meaning of space and universe. ‘We are expanding it' is the translation of the plural present participle ‘musiuna' of the verb ‘ausaa' meaning ‘to make wider, more spacious, to extend, to expand' (The Bibl,e the Quran and Science).  This fact was explained in the Qur'an in a time when telescopes and similar technological advancements were not even close to being invented.

The Quran was revealed to Prophet Muhammad (Peace Be Upon Him) 1400 years ago. The Arabs at that time had a little knowledge about astronomy, nor were they interested in it. They were experts in writing poems and had a very developed oral tradition. In addition, Prophet Muhammad was illiterate. Assuming this knowledge was written in the ancient books, there is no chance that Prophet Muhammad (PBUH) read this fact in such a book or someone told him that because such information was of interest of any body at that time. The only possible explanation for this is that Muhammad is a prophet of God, who revealed this fact to him.

Source: www.Islamweb.net