What was the big bang?

It wasn’t an earthquake, it wasn’t the electricity network, it could have been a meteor.

The source of the ‘big bang’ noise heard across the Latrobe Valley on Saturday night remains a mystery.

The Express contacted local power stations, Geoscience Australia, police, fire brigades, electricity distributor AusNet Services, the EPA and WorkSafe to try to pinpoint the sound’s origin.

All were at a loss to explain the cause.

Residents flooded Facebook with their own big bang theories including fireworks and a meteor. Some reported seeing a flash of light.

According to Australian National University astronomer Dr Brad Tucker, the meteor idea isn’t so ‘out there’.

“Two hundred tonnes of meteor debris (falls) to earth every day,” Dr Tucker said.

“It very well could have been a good-sized meteor which… when it hit the atmosphere, caused that sound.

“There would have been a quick flash (of light) or a bright fireball in the sky. It breaks apart and comes down.”

Dr Tucker said he had not received any reports of meteors in the area at that time, but it was “highly possible and probable” a meteor was responsible for the noise.

Whether of interstellar origin, or not, one piece of the sound puzzle appears to have been solved by the Bureau of Meteorology.

The reason the baffling blare was heard over such a large geographical area was a weather phenomenon that trapped sound, effectively turning the Valley into a “great big long trumpet”.

Senior forecaster at East Sale, Roger Lurz said a large high-pressure system was sitting over the region on Saturday, generating a subsidence temperature inversion.

“It’s not uncommon for that to come down to the level of the surrounding hills,” Mr Lurz said.

“Temperature inversions can trap sound waves. Basically that turned the whole Valley into one great, big, long trumpet.

“It could have been a sound that occurred quite a distance away and instead of spreading in all directions, it spread down the Valley and amplified.”

Mr Lurz said this could have been exacerbated by a nocturnal inversion, which happens most nights.

He said it was possible for the sound to cause vibration in buildings, as reported by some residents.

The noise was described on social media as a “thump” a “bang” and an “explosion” occurring around 10pm on Saturday.

Latrobe Inspector Dean Thomas said there were no reports to police of any incident “that you would expect a noise like this to come from”, while AusNet Services received no reports of significant damage to the electricity network.

Geoscience Australia said there was no earthquake in a 100 kilometre radius around Moe between 9pm and 11pm.