Ball of light floating in sky near main freeway in Milwaukee.

At approx. 6:50am on April 3rd, I was on my way to work, driving on the freeway 794W to ward Madison.  I was driving past the Marquette University campus, when I noticed a very bright light shining in the still dark sky at about 30 degrees to my left and up slightly.
I immediately thought it was an airplane approaching.  I continued to watch it, thinking, “Wow, what a bright light.”  I really was brighter than any plane light I have ever seen.  It was only one color (a yellowish white, not a bluish white).  It was then I thought why is there no flashing?   The light stayed solid the whole time.
Then as I kept watching, I waited to see if it would change or get closer or keep going to the side so I could see what sort of plane it was.  But, I was amazed to notice that it never moved.
That really startled me, so I really now strained to keep an eye on it for about 30 more seconds…no movement.  As I was driving on the freeway, I had to occasionally divert my eyes back to the road, and at that point I did once again, but when I looked back, the light was gone.  I slowed the car down and scanned the whole sky out my left window.  No lights.  There was nothing at all in the sky.
Also, the weather was completely clear.