This weekend the Kobuk 440 sled dog race is taking place in arctic Alaska.  The start and finish is in Kotzebue and the trail takes the teams 440 miles through the Kobuk Valley.  It is April, which means the days are blindingly long, over 14 hours of daylight now, and though the temperatures are considerably more mild there are still all the dangers of winter travel in the arctic--the challenges of river ice, the isolation of the wilderness that deftly punishes the incapable and the unprepared.