BBC News Hangout: Your Space Questions
As applicants begin signing up for a Dutch organisation's project to send people to live on Mars, many people are once again pondering the future of space exploration.
The BBC's Science Editor David Shukman took part in a BBC News Google Hangout with some of those applicants, to talk about the prospects for people in space.
Given the opportunity, would you want to blast off into space?
Even if you wanted to travel outside the Earth's atmosphere, would you want to settle on a satellite, or another world?
Do you think there should be limits to the exploration of space?
What do you want to ask our guests who have put their names down for the Mars One project?
In times of economic hardship for many, do you think space exploration is worth the money?
The hangout was live on the BBC News Google+ page
If you missed the live broadcast, you can see the highlights on World Have Your Say on Friday at 15:00GMT on BBC World News.