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I reviewed the video. It is very likely a weather balloon that burst.
The small dot "orbiting" the balloon was the radiosonde that was
attached below it with about 70 to 100 feet *of string.
The weather balloon was likely released by the National Weather
Service (NWS) upper air station in Oakland, California, at about 3:00
PM local time.
Here is a video of a NWS weather balloon burst taken by a NWS
meteorologist through a telescope:
Upper Air Observations Program
NOAA National Weather Service Headquarters
United States Department of Commerce