We Need Three Planets to Keep the Human Race Alive, NASA Scientist Says

We Need Three Planets to Keep the Human Race Alive, NASA Scientist Says | Motherboard: "It’s no secret that uncurbed climate change and population growth are going to (and already have) put stress on the planet. But the situation is getting so bad that one prominent NASA scientist says we have to start thinking about terraforming Mars and that, in order for the human race to survive at current levels, we will eventually “need at least three planets.”"