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.
Only around 180 impact craters have ever been discovered on Earth and around 30 per cent of them contain important natural resources of minerals or oil and gas. The largest and oldest known crater prior to this study, the 300 kilometre wide Vredefort crater in South Africa, is 2 billion years in age and heavily eroded.
The Caloris Basin. The Caloris Basin is the largest feature on the surface of Mercury. This crater was formed by the impact of a large meteorite in the early formation of the solar system. We only know what half of the crater looks like, because the other half was in darkness when Mariner 10 flew by the planet.