Going into space is a cherished dream for many, fuelled by sci-fi movies and the successful Nasa missions.
The space shuttle tragedies (Challenger in 1986 and Columbia in 2003, both of which exploded in flight, killing all passengers), and the retirement of the U.S. shuttle fleet last year, cast a pall over the space programme. But this is now lifting.
As the first spacecraft operated by a private firm to make the trip to ISS, the Dragon's flight may signify the true beginning of space travel as a viable commercial enterprise, accessible to ordinary people in the near future.
Yet critics say space travel remains excessively risky, and imagining we can succeed at it is foolish and arrogant. How dare we think we can thrust ourselves into a completely alien environment for which we are hopelessly ill-adapted and get away with it? Surely it's madness.
Yet our more familiar forms of transport were considered “insane” once too. The dangers have lessened as safety measures have improved, but we still take a risk every time we board a plane or, particularly, get behind the wheel.
Air and road travel don't present challenges to the human body quite as extreme as outer space, but we aren't physiologically adapted to them either; our technological progress outstripped the pace of our bodies' evolution long ago, but we're so accustomed to these forms of transport now we think of them as “normal”.
We're not designed to hurtle along a road at 120km/hr, nor save ourselves if we crash at that speed. Our internal clocks aren't evolved to fly back over mutiple time zones, and our bodies don't take kindly to the canned air and immobility of long-haul flights.
But we do it anyway, because our curious, adventurous species loves to travel and explore, and no doubt always will. Just as long as we remember, whether it's by bicycle or starship, to always take the best possible care of ourselves as we venture forth.
- Olivia Rose-Innes, Travel and Enviro Health Editor, May 2012