A US astronaut has become the first person to conduct a podcast from space.

Mission specialist Steve Robinson recorded his message to the world onboard the shuttle Discovery on the last day of its latest mission to resupply the International Space Station. Against the background noises of the shuttle he explained what had been achieved on the flight and his experience of spacewalking.

"That was, I would have to say, the most fantastic experience of my life," Robinson said.

"Just incredible to be way out there on the end of that arm all by myself and see no evidence of humans anywhere. Just me and the Space Station and the Space Shuttle from a view that neither I nor anybody else has ever seen, and watch the sun come up over the bottom of the Space Shuttle, and get to sort of drink in that big view."

Nasa has made the audio message available for download from its website and further broadcasts are expected on future missions.

Audio visual systems are very important to the shuttle crew. Every morning on missions the crew are woken with music, sometimes chosen by flight controllers on earth. For this latest mission the theme from Star Trek: Enterprise was used.