The culprit turned out to be an explosion at a Con Edison plant in Queens. Miraculously, there were no injuries, except perhaps to the feelings of those who truly wanted to meet some aliens.

[Read the full story on the explosion.]

Times reporters will be following the story all day, so check back for updates.

For now, here’s what we know:

• The cause: Mayor Bill de Blasio said the light was caused by an “electrical surge” at a Con Ed substation in Astoria, at the northern tip of Queens.

A Con Edison spokesman, Bob McGee, said early this morning: “What people were seeing was an electric arc flash. The electrical arc of that magnitude is similar to a thunder and lightning event.” The sound people heard was “the arc striking the ground.”

The Police Department described it, bluntly, as a “transformer explosion.” The reason for the explosion remained unclear this morning. The authorities have not mentioned any possible contamination from the blast.