On the afternoon of March 5, 2011, the floor of the Puʻu ʻŌʻō eruptive vent on Kīlauea's east rift zone collapsed and the summit caldera began to deflate rapidly as magma was drawn into the east rift zone near Napau Crater. A few hours later, lava began to erupt between Napau and Puʻu ʻŌʻō marking the start of the Kamoamoa fissure eruption. The eruptive fissure reached a length of about 2 km over the next several days, with activity jumping between different fissure segments and then gradually declining. The eruption ceased on the night of March 9, and it was 17 days before lava again appeared on the surface of the volcano, filling the collapse crater at Puʻu ʻŌʻō The Kamoamoa fissure eruption was spectacular and caused major changes in Kīlauea's 1983-present east rift zone eruption. Join Hawaiian Volcano Observatory geophysicist Mike Poland for a discussion of this fascinating event. In addition to information about the eruption itself, Mike will describe activity that preceded formation of the fissure and Kīlauea's current status as the volcano continues to recover from the Kamoamoa eruptive event.