I was working on a house, in deerfield beach. I was at the same location three days prior,and saw two ufos.This time,i brought a pair of binoculars,and a spotting scope with me.I was only on the job five minutes,and was looking out to the ocean. I saw an oval shaped,black object shoot out of the ocean,on a radius,and go back into the ocean. It must have been about a half mile out,and went fifty to one hundred feet in the air. After i saw the object,i was pretty scared. I didnt even want to turn my back to the ocean,to work. I did turn my back to the ocean,and start to get organized to start to work. I turned my back for about thirty seconds. When i turned back around,i saw a rainbow. Knowing the biblical meaning of a rainbow,i was instantly calm. So i went ahead and finished my work. Before i left i set up the spotting scope,and looked through it for about three minutes. I didnt see any other objects. I packed up my tools and went back to the shop for the day.