An astronaut, accidentally, dropped a mirror as he stepped out off the International Space Station for battery work, adding to the millions of pieces of junk that already orbit the Earth. The lost item poses no threat to either the station or the spacewalk, NASA clarified. According to Commander Chris Cassidy, the mirror floated away at a foot per second after getting detached from his spacesuit. A small mirror is worn by spacewalking astronauts on their wrists to get better views. He wasn't aware how it fell off as there was no thread damage, said Cassidy. He along with Bob Behnken conducted the first four spacewalks to replace old station batteries. Their spacewalks are likely to continue through July.