flying over the western part of the country, according to the BBC's media partner CBS News.
The object has been determined to be non-threatening, but its origin and purpose is unknown.
A US official told CBS the balloon was seen on Friday over Colorado, drifting east.
A year ago, the US shot down a Chinese balloon after it crossed the country from Alaska all the way to the east coast.
That encounter last February caused a diplomatic crisis between Washington and Beijing.
