As an aside, I feel it is entirely mandatory for us to go further out into space in the future, even if its only colonising Mars and some moons of Jupiter; one day our Sun is going to peter out and die, taking Mercury, Venus and Earth with it.
With the sun gone aswell, even if we have colonised as far as Jupiter's moons, we still have to think about the problems of no heat and light from the Sun, no solar energy and an alternative has to be found.
A great story in the manga 2001 Nights had a ship travel protected in an asteroid of ice at STL speed to find another Earth-like planet to colonise. The humans on the ship were frozen samples to be made into fetus' and raised on ship by androids when they reached a planet and spent some time in orbit until the babies grew to a suitable age.
Heres the twist;
the ancestor of the donors for the ship in the future tracked where the ship would head and used their FTL ship to terraform the planet and then left, leaving it a beautiful garden world for them, hundreds of years before the ship above reached it.
In all seriousness though, we are a doomed race if we do not reach out to space to move home before our Sun dies.