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.
The second largest crater in the world was formed by the impact of a comet according to a 2014 study by researchers in Canada and Ireland. Colliding with Earth almost 1.85 billion years ago, the estimated diameter of the crater is 81 miles (130 km).