Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Distraction
Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Requested ATC Assistance / Clarification
Equipment / Tooling; Human Factors
All of a sudden; the Captain stopped mid-sentence and said; 'Look at that!'  He pointed to the 1:00 right position; and we passed by a large; round; unknown object to the right at our altitude.  Based on the speed of passing; it seemed to be stationary.  It was large (much larger than a Mylar balloon); dark gray and silver/shiny; stripes (stripes of its form/shape) from top to bottom.  It seemed to have a pinch point at the bottom.  I didn't see anything attached; but the Captain said he saw a rope or something dangling behind it.  Soon after our shock; ATC gave us a handoff and we reported the object.  He was unaware of its presence. I reached out to the [nearby]  pilots to see if anyone knew anything.  One pilot responded: 'We got a message from our chief pilot this morning - balloon off SWO 100 radial 12.4nm & tethered balloon by Company.' The message the pilots in SWO received correlates with the location of our event.  I've never known of a tethered balloon at 32;000 feet.  Makes one wonder if this balloon got loose; especially given the rope the Captain saw.  If so; shouldn't ATC have been notified?  A bit more right today; and I may not have been able to write this report; along with the more than 200 people we had onboard.
An Air Carrier pilot reported a close encounter with an unidentified object which the reporter researched and believed it may have been an untethered balloon.