Mystery Noise Over Greater Danbury Area Last Night — Extraterrestrials?

Last night, I was in my kitchen talking to my wife a little after 8:30 but definitely before 9:00, when we heard a noise we should not hear in this area.

To me, it sounded like a commercial plane flying right over our house. I ran outside and around the property and saw nothing other than the lights of some smaller airplanes that completely make sense for this area. I jumped on Facebook and asked this question:

There was immediate response from people all over the Danbury area and way beyond.

• Kate D. - "Yes!!! We live off of Hayestown and we are sitting here watching TV and heard it, I was like holy crap!"
• Dave T. -  "Heard it in Ridgefield too."
• Andrew W. - "Yes over near Chuck’s Steakhouse, it was a
  big plane and very low by the sound of it."
• Christine C. - "It was over Woodbury as well."
• Debbie P. - "Yes!!! In Harwinton. Crazy loud. I couldn’t see it but I thought it was going to crash."

Those were just some of the comments. Different towns checked in far and wide with the same description all around the same time.

Then, from there, the thread descended into chaos. It was a typical Lou Milano thread, chock full of "Goonies" and "Ancient Aliens" GIFs and memes. We topped that off with a side of wild speculation.

Everyone I spoke to about it, heard the same thing all around the same time. No one saw much of anything and here we are with no answers. Even this morning on the Ethan and Lou show, I asked Danbury Mayor Mark Boughton about it. Here's how that went:

Did you hear it? Any ideas?