The moon, the earth and the sun as well as the stars in all the galaxies are always turing on its axis and travel in their own fixed orbits. The specific orbits followed by a star, a planet or the moon prevent them from colliding into one another. This phenomenon is explained in the Quran in Surah 36 (Ya-Seen):37-40, as follows:
37. And a Sign for them is the Night: We withdraw therefrom the Day, and behold they are plunged in darkness;
38. And the sun runs his course for a period determined for him: that is the decree of (Him), the Exalted in Might, the All-Knowing.
39. And the Moon,- We have measured for her mansions (to traverse) till she returns like the old (and withered)lower part of a date-stalk.
40. It is not permitted to the Sun to catch up the Moon, nor can the Night outstrip the Day: Each (just) swims along in (its own) orbit (according to Law).
Comment: according to Law? Law of gravity and centrifugal/centripetal force?
These ayat not only explain that there are specific orbits for each star, sun, earth and the moon, but also implicitly explain that all these masses are spherical in shape and not flat as people thought not too long ago. The spherical shape of all these masses is explaned elsewhere in the Quran.
The earth tilts on its axis according to season so that each part of the earth can receive sunlight at certan time of the 365 days of the earth's complete circle around the sun. In this way, the inhabitants of the earth can recieve the four seasons, which makes up a year.
Meanwhile, the moon completes a circle around the earth in 30 days, that will make a month. Thus, the people can calculate the days, the months and the year. This is explained in Chapter 10 (Surah Yunus (in the Bilble = Jonah)):Verse5.
"Translation in modern Englih by Dr. Annis Ahmed : He is Who has made the sun self-luminous and the moon radiant (reflecting the sun light) and programmed for it stages that you may know the number of years and (keep) the account. Allah did not create that but in reality. He explains the signs in detail for a people who have knowledge."
"Translation in classical Englih by Ibnu-Kathir: It is He Who made the sun a shining thing and the moon as a light and measured out for it stages that you might know the number of years and the reckoning. Allah did not create this but in truth. He explains the Ayat in detail for people who have knowledge."
Comment: One must note in this ayat that the Quran explains that the sun is the one that gives out the light. The moon meerly reflects the light from the sun. This fact has only been discovered relatively recently the astronomists and the scientists.
Another thing to note is the word "haq" which is translated as "reality" or "truth" in the two translations above. The word "haq" may also be understood as "exactness" or "benifits and usefulness". All of the translations may be correct since the modern findings match the facts inscribed in the Quran in all respects, namely the truth about orbits and the exactness of orbit and orbiting speed. For example,if the moon travels faster than the current speed, it will disappear into the outer space, and if it travels slower, it wil be on collision course with the earth).
It is also true that wahtever is created has benifit to the people, environment, plant and animals or the stability of the earth and universe systems.
If you study the chemical and molecule interactions in the human cells, you can appreciate how exact these chemical interactions are occuring. One mistake made, the cell will not be functioning and the whole array of our body function will be in jeopredy. That is to say our whole body will not function properly. All kinds of deficiency diseases can occur if just a single defect occurs in the body system. Study the subjects "Cell Biology" and "Immunology", and you will appreciate this.