A spacewalking astronaut on Friday added a small mirror to the millions of pieces of junk orbiting the Earth, as he lost the small object from his space suit, while stepping out of the International Space Station.
U.S. Commander Chris Cassidy said the mirror floated away at about 0.3 meters per second. Mission Control said the mirror somehow became detached from Cassidy's spacesuit. Spacewalking astronauts wear a wrist mirror on each sleeve to get better views while working.
The mirror is just 12 centimeters by roughly 8 centimeters and came loose as the ISS was in darkness. Once he was in sunlight, Cassidy inspected his sleeve for clues that might explain how the mirror came off but told Mission Control he found no evidence of thread damage.
Cassidy and fellow astronaut Bob Behnken have conducted the first of at least four spacewalks to replace the last in series of old nickel-hydrogen batteries with new, more efficient lithium-ion batteries. The batteries store energy collected by the station's solar panel arrays.
Their spacewalks are expected to continue through July before Behnken returns to Earth in August aboard a SpaceX Dragon capsule.
Behnken and Doug Hurley made history at the end of May with SpaceX's first astronaut launch.
This was the seventh spacewalk for both men. Each has spent more than 30 hours out in the vacuum of space.