Duel of the Winds - When winds collide: A Wolf-Rayet star (WR) and its giant companion (O) do battle. Like two ancient storm gods using nature’s weaponry to wage war, this pair of ultra-massive stars has sent their fierce stellar winds smashing together across a region the size of our solar system. Now, astronomers have used the National Science Foundation’s Very Long Baseline Array of radio telescopes to track the moving collision zone. One of the combatants is a true behemoth weighing in at some 50 times the mass of our own Sun. But the other, a comparative lightweight having “only” 20 times the mass of Sun, belongs to a category known as Wolf-Rayet stars–meaning it is on the brink of exploding as a supernova. This has been added to Astronomy Resources Subject Tracer™ Information Blog.