The Discovery of a Rare WO-type Wolf-Rayet Star in the Large Magellanic Cloud1

While observing OB stars within the most crowded regions of the Large Magellanic Cloud, we happened upon a new Wolf–Rayet (WR) star in Lucke–Hodge 41, the rich OB association that contains S Doradus and numerous other massive stars. At first glance the spectrum resembled that of a WC4 star, but closer examination showed strong O vi λλ3811, 34 lines, leading us to classify it as a WO4. This is only the second known WO in the LMC, and the first known WO4 (the other being a WO3). This rarity is to be expected due to these stars' short lifespans as they represent the most advanced evolutionary stage in a massive star's lifetime before exploding as supernovae. This discovery shows that while the majority of WRs within the LMC have been discovered, there may be a few WRs left to be found.