Continuous positive airway pressure (CPAP) machines are used to maintain an open airway in patients diagnosed with obstructive sleep apnea. The machine functions by blowing pressurized air into the airway via mask at a setting determined by sleep study and prescribed by a physician.
Also the second largest impact structure on Earth, the 1.85 billion years old Sudbury crater in Canada, hosts world-class mineral deposits - in this case nickel-rich minerals that were melted and concentrated by the extreme heating caused by the impact.
Map all coordinates using OSM. Map all coordinates using Google. This list of impact craters on Earth contains a selection of the 190 confirmed craters given in the Earth Impact Database. To keep the lists manageable, only the largest craters within a time period are included. The complete list is divided into separate articles by geographical region.