X-files-style sounds have been recorded 36 km above the surface of our planet. The data was recorded as part of a student experiment. Some of the sounds remain a mystery.
An image of the recording. Photo credits: Daniel Bowman/University of North Carolina.
Strange complex sounds have been captured 36 km above the surface of the Earth by a NASA balloon sent out by graduate students. The sound waves, known as atmospheric infrasound, are recorded to be below frequencies of 20 hertz, out of the range of human hearing. When they were sped up, the noises sounded like paper rustling, with some crackles and static. They were also described as screaming as well.
“It sounds kind of like The X-Files,” Daniel Bowman, a doctoral candidate in geophysics at the University of North Carolina.
Daniel Bowman is the one who created the equipment that was used to record the weird sounds. He constructed microphones able to capture infrasound waves. These were attached to NASA’s High Altitude Student Platform (HASP) which is a huge helium balloon. The latter was built as a way of promoting interest in aeorospace among students.
The balloon was made to fly to an atmospheric spot known as “near space”: it is at the level of aeroplanes, but not going beyond the stratosphere which is at 100 km – it arrived there within 9 hours of flight. The event marked the first time sounds were recorded in near space from a NASA student balloon experiment in more than 50 years.
“I was surprised by the sheer complexity of the signal. I expected to see a few little stripes,” Bowan said in a statement.
“There haven’t been acoustic recordings in the stratosphere for 50 years. Surely, if we place instruments up there, we will find things we haven’t seen before.”
What is the origin of the sounds? Natural occurrences are sometimes behind infrasounds, like earthquakes and storms. But, still, some crackles and screams that were recorded remain a mystery.
The scientists attempted speculating as to their source(s). They affirmed that some signals were from a wind farm located under the balloon. Others were from ocean waves crashing onto the shore, clear air turbulence, gravity waves, and vibrations built up from the balloon cable.
More will hopefully be found out about the strange infrasounds during another experiment planned for the 2015 HASP balloon launch.