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.
2. Chicxulub. The Chicxulub crater is 112 miles wide, about the distance from Los Angeles to San Diego, and is now underneath the Yucatan peninsula in Mexico. According to scientists, the asteroid hit Earth 65 million years ago, thought to be a hint on what caused the mass extinction of the dinosaurs. (NASA). 3. Sudbury. The Sudbury Crater, in Ontario, Canada, is believed to been formed by a meteor blast over a billion years ago.