The crew on board the International Space Station (ISS) have paused in silence for six people killed in a shooting in Arizona which left US congresswoman, Gabrielle Giffords, seriously wounded.

The ISS Commander, Scott Kelly, who is Ms Giffords' brother-in-law led a tribute to the victims. Ms Giffords' husband, Mark Kelly, is also an astronaut.

"As I look out the window, I see a very beautiful planet that seems very inviting and peaceful," said Cmdr Kelly. "Unfortunately, it is not.

"These days, we are constantly reminded of the unspeakable acts of violence and damage we can inflict upon one another, not just with our actions but also with our irresponsible words."

"We are better than this. We must do better," he said.