No prosaic explanation can be formulated at present because the basic facts remain garbled. But there are some historical analogs that may provide
suggested avenues of genuine research.
Here's one that immediately comes to mind:
January 27, 2001 // Agence France Presse
An airport in southern Siberia was shut down for an hour and a half on Friday when an unidentified flying object (UFO) was detected hovering above its
runway, the Interfax news agency reported.
Most of the debate is summarized here:
As it turned out, the runway that the taxiing aircraft stopped on was pointed directly at the horizon where brilliant Venus was setting. The crew
reported "a bright UFO", but never mentioned two bright objects, or a "UFO next to Venus".
When Venus set, the crew reported that the UFO had flown away.
The Hangzhou airport runway is 07/25, that is, aligned 70 degrees (just north of due east) and 250 degrees (just south of due west).
The best reconstruction I've seen is that the UFO was first spotted by the airliner crew on their approach to the airport.
Internet software can provide insights into what would have been in the sky along their line of sight (two possibilities -- either direction).
Hint: On one approach, something whose name begins with the letter 'V' was in front of them. No, not the 'Virgo' constellation.
Apparently when the airport tower was informed of an object over the airport, they searched their radar -- and contradictory stories are circulating.
Either because they saw something, or (more likely, as claimed in later reports) they saw nothing, they developed a prudent concern that some aerial
vehicle was somewhere in their airspace but they couldn't locate it to determine that normal landings were safe.
They did exactly the proper thing -- halt all landings until they could be sure their airspace was clear.
Note also that a celestial object low to the horizon (again, check software packages to see how low) would have been clearly visible to airliner crew
and passengers, but probably too low to be seen by ground observers because of horizon clutter (hills and buildings).
In such a dramatic situation, people are likely to run outside and photograph any lights they see in the sky. That's actually very common.
Without the direct testimony of the direct witnesses, no theory worthy of the name can yet be argued for.
But the Barnaul precedent -- aircrews and airport operators spooked by a light in the sky, doing the prudent thing -- may have a lot to teach the