‘This is futuristic stuff’: Will we one day sail through space on light alone?

Photograph: Andrzej Mirecki/CC BY-SA 3.0

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s far as space travel goes, the 2020s are an exciting time. Elon Musk is cutting the cost of blast-off from Cape Canaveral. Low Earth orbit has never been so alluring but once we actually get there, what could we do next and how could we possibly afford it?  

Well, we’ve all seen Star Trek and, in the end, we’re all expecting to see interplanetary travel become routine. If you look at it optimistically, we might be able to get four people back onto the Moon by about 2025. All of this, nearly 60 years after Neil Armstrong achieved exactly the same thing in 1969.  

But what if we wanted to go further than that and with more than four people? What if we wanted to explore the asteroids and the planets in our solar system using real people who were looking to make it affordable and routine? How could we do that?