What did I see over Lake Michigan?

What did I see over Lake Michigan?
Time: December 23 2024 00:50:52 UTC 
Location: somewhere over Lake Michigan 

Note these are two videos the first video cuts after I show the instrument cluster the second video is a zoomed in video I took a few minutes after the first video. 

I was flying  eastbound over Illinois when I noticed a flashing light off to our 9 o’clock. At first, I thought it was another aircraft. By the time we reached Chicago, it had moved to our 11 o’clock and was high. That’s when I recorded the first video, where you can also see my location and altitude. I held contact for at least 45 minutes to an hour total. Tracking it from my 9 o’clock to my 4 o’clock over that time period.

If I had to guess, I’d say this thing was cruising at 50k - 60k feet. It was also traveling quite fast, appearing to cross the Great Lakes in minutes.

It looked like two white lights, one of them pulsating. It did not look like typical aircraft lighting even when looking through my binoculars. 

We didn’t see anything on TCAS, and ATC didn’t detect anything either.

My question is: what could it have been?