During their work, the astronauts let a white satchel-like bag of tools inadvertently slip away.
Flight controllers spotted the tool bag using external station cameras and determined it didn't pose enough of a safety risk to warrant attempts to retrieve it, NASA said.
The object entered the Earth's orbit just ahead of the space station, where it is expected to circle the planet for months before eventually entering the atmosphere and breaking up, according to EarthSky.org.
Experts say while it remains in orbit it should be easy to spot with binoculars or a telescope because its white surface reflects rays from the sun.
As the bag gradually falls, it should appear between two and four minutes ahead of the International Space Station, according to The Indianapolis Star. The station can be tracked online at SpotTheStation.nasa.gov.
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