Why Titan is the only colonizable world in the solar system beyond Earth

Cold is easier to deal with than the raging heat of Venus. The Moon and Mars are bathed in dangerous radiation. This means Titan is humanity's best existential insurance policy. Charles Wohlforth and Amanda Hendrix, authors of Beyond Earth: Our Path to a New Home in the Planets, explain:

It's cold on Titan, at -180C (-291F), but thanks to its thick atmosphere, residents wouldn't need pressure suits-just warm clothing and respirators. Housing could be made of plastic produced from the unlimited resources harvested on the surface, and could consist of domes inflated by warm oxygen and nitrogen. The ease of construction would allow huge indoor spaces.

Titanians (as we call them) wouldn't have to spend all their time inside. The recreational opportunities on Titan are unique. For example, you could fly. The weak gravity-similar to the Moon's-combined with the thick atmosphere would allow individuals to aviate with wings on their backs. If the wings fall off, no worry, landing will be easy. Terminal velocity on Titan is a tenth that found on the Earth.

How will we get there? Currently, we can't.

Oh well. Doom it is, then!