Ask Yan - Will we ever colonise another planet?

There is no problem in colonizing a planet such as Mars, the technology to do so has been in existence since the 1960s. However the colony would be small and probably limited to scientific and engineering specialists for the foreseeable future. If we wished to have a large colony on Mars, we would need to further develop nuclear technologies for power, test and develop biological systems to grow food, prepare habitation on or under the surface to guard against UV radiation, create oxygen to breathe and for chemical rocket fuels, get water from the Martian soils or atmosphere and develop the space infrastructure necessary to host a colony on the planet. This will take some time and will rely on a political enterprise on Earth willing to fund and support the colony for several decades if not longer.

An alternative is to detect an Earth-like planet and send a mission to colonize it if there are no indigenous intelligent life forms there. This presents its own problems in interstellar travel, timescale to get there and the fact that any colonists would be completely independent of their home world and utterly alone. This will take massive technological advancement, political and commercial international cooperation and enormous self sacrifice on the part of the colonists.

It can be done, but is probably a far future endeavour.

- Answered by Martin Griffiths, 10 July 2009