World One of Antarctica’s biggest glaciers has a giant hole under it. What would happen if it collapsed? February 19, 2019February 20, 2019Brett Molina, USA TODAYComments Off on One of Antarctica’s biggest glaciers has a giant hole under it. What would happen if it collapsed? Researchers discovered a giant cavity inside Thwaites Glacier, considered one of the most dangerous in the world. What happens if it collapses?