Terraforming (Earth-forming) other planets, also known as planetary engineering, seems like a task still centuries away for mankind to (31) . However, it is a vigorous topic that attracts both popular and (32) interest. Why should the (33) of terraforming other planets be studied when it may be centuries (34) we know enough to even decide if it’s a good idea Mankind is getting more and more (35) facts about other planets. The atmosphere of Venus has been (36) ; (37) have surveyed the surface of Mars; Mercury, Jupiter and Saturn have been studied by spacecraft. (38) have been answered; new questions have been (39) , and enough hard data is right now becoming available to allow us to make the first (40) of planetary engineering. In the past, people (41) excellent ideas about terraforming have kept them to themselves, or buried them in a desk drawer (42) they did not realize that anyone else was interested. But now, a (43) circle of people has begun to do this kind of work. For instance, NASA funded a project on transforming Mars. There are several strong reasons (44) demand that the possibilities of terraforming be studied carefully. First, it’s an (45) idea of a possible future for human beings. Such thinking has a valuable role in (46) options for our future directions. Secondly, the techniques of terraforming will (47) help contemporary technologies in weather and (48) control. Thirdly, such study (49) assist us in detecting any possible existence of extraterrestrial intelligence and (50) civilizations on other planets.