The Mysterious Train Sound Quiz

What was the unique characteristic of the sound known as 'The Train'?

• It was recorded at 32 times normal speed.

• It was only audible in the Atlantic Ocean.

• It had a steady, repeating frequency similar to a train horn.

• It was first heard in 2007.

What was the original purpose of the underwater microphones that recorded 'The Train' sound?

• To measure ocean temperatures.

• To track Soviet submarines during the Cold War.

• To study marine life in the Pacific Ocean.

• To monitor volcanic activity underwater.

How far could 'The Train' sound be heard across the Pacific Ocean?

• Thousands of miles.

• Only within a small area.

• Hundreds of miles.

• Only a few miles.

What is one theory proposed by NOAA for the origin of 'The Train' sound?

• It was caused by underwater volcanic eruptions.

• It was produced by a large marine animal.

• It was generated by underwater mining activities.

• It was likely caused by ice sheets in Antarctica.

What is a common skepticism about the explanation for 'The Train' sound?

• That it was a hoax created by researchers.

• That it was actually an underwater train.

• That it was caused by a new species of fish.

• That it was caused by ice sheets in Antarctica.