| 29.08,18. 03:34 PM |
Houses shake, windows rattle as 'scary' fireball lights up the Perth sky with a sonic boom
Photo: A meteor streaks through the sky over Perth. (Supplied: Dylan Teede)
The sky above Perth and the surrounding area was lit up overnight by a fireball that is believed to have been a meteor entering the atmosphere.
The Department of Fire and Emergency Services was inundated with calls at 7:40pm from people who said they had seen a fireball streak across the sky.
More than one concerned caller suggested it could be a UFO while others were more concerned the flash could start a fire.
The Perth Observatory was sent dozens of videos taken from CCTV cameras and dash cams which captured the phenomenon.
'They were thinking the sky was falling'
Social media was inundated with reports from people in the Avon Valley region who said they thought they felt the meteor hit the earth.
Rosena Cox lives in Caljie, 125 kilometres east of Perth, and was in the shower when she heard a sound that she thought was a plane crashing.
"I just heard this enormous bang, it sounded like an explosion and I just thought 'what on earth was that' because it was so intense."
Robyn Garratt, from the town of York 100km east of Perth, was among those who witnessed the incident.
"We heard the boom, we saw the light, we just thought it was lightning to start with, but the boom that came after it was definitely not thunder," she told ABC Radio Perth.
"It shook the whole house, the windows, the dog went psycho.
"In York, people felt a lot more than that. They all went running outside thinking the sky was falling, basically."
The fireball search begins
Scientists from Curtin University have been scrambling to determine if and where the meteor hit the ground.
Director of the Desert Fireball Network, Professor Phil Bland, said initial observations indicated there was a fair chance the object made it to Earth.
"It was unusually bright so it must have been a big object, so that is really exciting," he said.
"The other thing is that people reported sonic booms, and you only get that if it goes through the atmosphere low down in the atmosphere, which is a very good sign.
"It also looks like we've seen it on multiple cameras which means that we'll be able to triangulate exactly how it came in through the atmosphere, what its position was, what its speed was, what its size was [and] work out where it came from in the solar system, and if any of it landed."
'Hearing sonic booms is a really big deal'
The Fireball Network monitors meteors that enter the atmosphere and also tracks those that land so they can be recovered and studied.
Professor Bland said most meteors travelled incredibly fast and completely burned up in the earth's atmosphere — with only about 2–3 per cent of those that were visible ever making it to the ground.
To stay intact through the earth's atmosphere a meteor has to be relatively large and also needs to travel slower than about 4 kilometres per second.
"The average velocity at the top of the atmosphere is 17 kilometres per second — if it got down to about 4 it probably survived," Professor Bland said.
"Hearing sonic booms is a really big deal. That means it got down really low and was going, from our point of view, comparatively slow."
The Desert Fireball Network expected to be able to calculate a location of the meteorite's landing before the end of the day.
Once a location was pinpointed, immediate attempts to recover the meteorite would begin.
"Meteorites are a great scientific resource in terms of working out how the solar system formed and how it evolved," Professor Bland said.
"When we actually have that context and we're able to say 'this comes from the outer solar system' or 'this comes from near Mars' that's so useful. So when we find one it's an incredible experience and just putting your hands on that is a fantastic moment.
"It's very emotional as well as scientifically satisfying."