The first visitors to Gliese 581 d may find it difficult to walk. With over 7 times the mass of our Earth, it is possible the surface gravity could be twice that of our planet. But it’s not the land that we want to explore here: this planet may be mostly water. And in that water may be life. This world is tidally locked to its star and is experiencing an atmospheric greenhouse effect. Yet the dark side of the planet is cold and possibly icy. In between these two extremes, in a transitional zone, may be a habitat that humans might colonize. In anticipation of that day, messages from Earth were transmitted from the DSS-43 70m radio telescope in Canberra, Australia, in August 2009. The earliest possible response from the Gliese system would come in 2049.