Maybe if we want to live forever and still have children then this is the only way.
Can We Terraform Mars to Make It Earth-Like?Space - 30-Jul-2018
Mars is a hopeful "Planet B" if Earth fails.
100 people needed to start trip to another starPhys.org - 15-Jun-2018
Would take 630 years to reach Proxima Centauri b.
Will we ever colonise an asteroid?BBC - 13-Jun-2018
Asteroids come in three types: stony, carbonaceous, metallic.