In the middle of the 'week' two wonders will appear in Heaven, John is back again in heaven. Some versions call them 'signs'. They are symbols of something and must be interpreted.
The first will be a Sun Clothed Woman. She is Israel. Israel is again and again compared to a woman, a married woman, in the Old Testament. The Sun Clothed Woman is described as being with Child and travailing to bring forth. Israel has been prophesied as being a Mother. Christ was to come from Israel. She went through many afflictions and judgment to bring the promised Child.
The second is the Great Dragon having seven head and ten horns and seven crowns upon his heads. His tail drew the third part of the stars of heaven and cast them to the earth. The Dragon stood before the Woman which was ready to deliver so to devour her Child as soon as it was born. There is no doubt this is Satan.