Researchers at NASA are puzzled after a student recorded never-before-heard hissing sounds 22 miles above earth. The spooky noises were recorded using infrasound microphones aboard a NASA student balloon experiment in Arizona and New Mexico and are only noticeable to the human ear after speeding up the recordings. It is significant to note that infrasounds are capable of travelling exceptionally long distances, making it even harder to locate where the sound initiates from. David Bowman, the student at North Carolina who recorded the eerie noises told Live Science: "It sounds kind of like The X-Files. There haven't been acoustic recordings in the stratosphere for 50 years," he explained to Live Science. Surely, if we place instruments up there, we will find things we haven't seen before."