It could be 1,500 years before  billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet   billion billions contact extraterrestrials galaxy humans languages life one other place possibility should signals space stars theories there yet