--What is the mystery object pictured above? It was spotted off Willow Avenue in Somerville early Friday, and Big Fat Whale was there to capture the thing in motion. [Big Fat Whale] --Tensions among racial groups in the Fire Department and tensions between the firefighters' union and the panel that is supposed to overhaul the department have collided. After the firefighters' union demanded that its members resign from the panel, a black firefighter refused......