Stars in The Book of Revelation

What is the meaning of stars in the Book of Revelation???

A star is used in the Book of Revelation to represent two meanings. The first meaning is symbolic and the second meaning is literal.

(Rev 1:20)
The mystery of the seven stars which thou sawest in my right hand, and the seven golden candlesticks. The seven stars are the angels of the seven churches: and the seven candlesticks which thou sawest are the seven churches.

According to the above scripture, a star is a symbolic representation of an ANGEL.

Who is THE MORNING STAR?

And I (Jesus Christ) will give him the morning star.
(Rev 2:28)

Yes, the answer is in Rev 22:16
(Rev 22:16)
I Jesus have sent mine angel to testify unto you these things in the churches. I am the root and the offspring of David, and the bright and morning star.
In the Book of Revelation, St. John has witnessed many stars falling to the earth. Truly, the earth can fall on a star as a star is a much bigger object, identified as another sun.

How can a star literally fall on the earth???
A star can represent even a fallen angel (Satan or any of his fellow angels - evil spirits). If you see a star or stars falling in the Book of Revelation, they represent Satan or his fellow angels.

Hence, all falling stars in the Book of Revelation represent fallen angels or evil spirit. Look at the below scripture:
(Rev 9:1)
And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.

When we read the first half of the above verse, we might have thought of this star as a kind of celestial object falling to the earth provided the second half of the verse had not revealed that it was an evil spirit. Let's look at some more of stars from the Book of Revelation, that are falling to the earth.

(Rev 6:13)
And the stars of heaven fell unto the earth, even as a fig tree casteth her untimely figs, when she is shaken of a mighty wind.
(Rev 12:4)
And his tail drew the third part of the stars of heaven, and did cast them to the earth: and the dragon stood before the woman which was ready to be delivered, for to devour her child as soon as it was born.
(Rev 8:10)
And the third angel sounded, and there fell a great star from heaven, burning as it were a lamp, and it fell upon the third part of the rivers, and upon the fountains of waters;

If the great star in Rev 8:10 represented any kind of single object from the space, how come it could touch two third of the revers on the earth as the revers are not connected with each other all over the earth??? 
Obviously, a great star is an evil spirit, sometimes Satan himself. Then we can imagine how it could touch the third part of the rivers on the earth.

However, some scriptures in the Book of Revelation refer to literal stars in the universe by the same term "STAR".  Look at the below scripture:
(Rev 8:12)
And the fourth angel sounded, and the third part of the sun was smitten, and the third part of the moon, and the third part of the stars; so as the third part of them was darkened, and the day shone not for a third part of it, and the night likewise.

Yes, the third part of the stars in Rev 8:12 represent real stars as they reduce their brightness or they become darkened.