Jack, there was a trail merge right before the collision, but in the back of my head I knew the other trail was closed due to lack of snow coverage on that trail and it was unskiable, THis skier overtook me on the same trail I was on....
For the record, I do agree with all the comments about looking behind you between turns, and I usually do that a few times per run. I guess tis run, mentally I thought I was the only one on it as it was 1st thing in the morning and when I looked at the top of the slope there was nobody even close. I guess there is always somebody faster than you on the slopes.......