WASHINGTON - Officials from 32 of the world's space-faring nations concluded a trio of summits on Friday to tackle expanding participation in the International Space Station and planning for eventual human expeditions to Mars.

Fifteen nations collaborated to build the space station, a permanently staffed research complex that flies about 250 miles (about 400 km) above Earth. On Wednesday, the Obama Administration announced its intent to extend station operations to at least 2024, four years beyond when it was slated to be removed from orbit.

"We're very happy to hear about extension," Xu Dazhe, administrator of the China National Space Administration, said Friday at the International Academy of Astronautics conference, one of three global space summits hosted in Washington this week.

"It means that by the time our space station is being built, we would have a companion up there," Xu said, speaking through a translator.

Please LIKE our Facebook page - it makes us stronger