The crews of the U.S. space shuttle Discovery and the International Space Station unfurled the orbital outpost's new solar wings Friday, after installing them on Thursday.

The U.S. space agency, NASA, says the new panels will double the amount of electricity available for science operations.

The extra power supply will also allow the U.S. and Russian space agencies and other partners to increase the station's permanent crew from three to six astronauts.

Four astronauts currently at the station took part in a special  with Voice of America Friday. VOA's viewers and listeners submitted questions.

Responding to a question on how living in space has changed the astronauts, American Sandra Magnus said she has seen how "incredibly thin" the Earth's atmosphere is and how "small" and "fragile" the planet is. She said Earth is "our spaceship" and that "we have to take care of each other."

Magnus is scheduled to return to Earth on Discovery in the coming days. The shuttle brought a Japanese crew member to replace her. Koichi Wakata will complete a four-month assignment in space. He is the first Japanese citizen to live aboard the station.