Scientists would like to place a huge mirror in space above the earth. It might be sixty miles wide. It would be used to catch the rays   of the sun. It would direct the sun's rays upon the earth as a child might do to make sunlight dance on the wall with a hand mirror. Why do they want to do this? The sun's rays could be helpful in many ways. They could light up cities by night. The warm rays could stop frosts   which might come at night and hurt fruit crops. They could melt   dangerous icebergs in the ocean. Perhaps they could change cloud movements and bring rain where it is needed. The strong light from the mirror could possibly   _  .
hurt fruit crops set fire to cities bring longer daytime shine through walls