Various companies are now working to settle on other planets. Discovery News asks; how long would it take and what issues would we face along the way?

We, humans, evolved on Earth, and we rely on our habitat on this planet. But perhaps we should look for habitat elsewhere to mitigate the potential risks of being a single-planet species, as Elon Musk said; “We’ve got all of our eggs in one basket here. We should try to protect that basket with everything we can but there’s some risks that are just extremely difficult to mitigate and some which we will ultimately not be able to mitigate. So, it just seems like the right thing to do, and then the next question is should we do it now, or should we wait for some point in the future, and I think the wise move is to do it now because the window of technology for this is open and it’s the first time that window’s been open in the 4.5 billion year history of Earth.”