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.
Found on the far side of the Moon, the diameter of this impact crater is equivalent to the distance from London to Athens. The massive Aitken basin measures 2,500 kilometres (1,600 miles) across and is the largest, deepest and oldest basin on the Moon. In fact, itâs as deep as six kilometres (3.7 miles) in some places. For comparison, some of the largest impact craters on Earth are only several hundred metres deep. The Aitken basin is thought to have formed about 4.3 billion years ago, just a few hundred million years after the formation of the Moon itself. Its origin, however, remains somewhat of a mystery.