The Atmospheric Neutral Density Experiment is launched from shuttle Discovery. The ANDE payload canister separated into two halves soon after release from the shuttle to eject two microsatellites. However, only one microsatellite successfully emerged from the canister. The other metal object seen in the video is the collar that connected the canister halves.
Source: NASA TV (11 min 31 sec MPEG-4 (H.264) file)
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