Hawthorne, California, USA based private Space firm SpaceX has pledged to compete with the Russian Soyuz price tag of around $50 million for taking astronauts on the return trip to the International Space Station, after the shuttles are put into retirement later this year.

SpaceX president Gwynne Shotwell told a US Senate committee on commerce, science and transportation that his company can "guarantee crew flights to the ISS for less than $50 million a seat".

With launch costs estimated to be around $400 million a time and maximum crew space of 7 fully loaded, the figures don't look like they add up at the moment. However, reliance on just one means of transporting crew to the ISS is not ideal, so this option I am sure will be welcomed.