Leigh Green's bolide photo
Bolides, or fireballs, are brightly burning meteors that have entered the Earth's atmosphere. Most small meteors burn up inside the atmosphere, and occasionally they bounce off the upper atmosphere before moving away from the Earth again. These provide spectacular but harmless light shows. Sometimes, however, they cause havoc on the ground.
The Chelyabinsk Event in February 2013 was an explosion caused by a meteor about 20m across entering the atmosphere. The explosion released about the same energy as the Hiroshima bomb. Damage was widespread, and several fragments were recovered.
Recovered fragments of meteorites are of significant interest to scientists, of course. But how do you find them?
The International Meteor Organisation records meteors and bolides reported by citizen scientists. These include visual records, mostly from all-sky cameras, and the occasional sound recording.
Scientists can use these to estimate the meteor's trajectory when it entered the atmosphere, as well as velocity, size and weight. Once the trajectory is estimated, they can even pinpoint the probable location where any surviving fragments can be found.
On 7 November 2020 a bolide was seen from locations in Scandinavia. https://www.imo.net/swedish-nov-7-fireball-as-bright-as-full-moon/. The IMO calculated that fragments might be found in the vicinity of Fröslunda in Sweden.
I've reported before that similar calculations led searchers to find fragments in Italy.
Perhaps we need something similar here.
On Valentine's Day, Victoria was treated to its own bolide. I was reading in bed at 10:41 when I noticed night turn to day for a second. I thought it was a car turning around in my driveway.
One of our customers, Leigh, was imaging Carina at the time. On his telescope, as well as his normal cameras, Leigh had a Go-Pro taking continuous 30-second images. If fragments made it to the ground, they'd probably be SSW of Leigh's position, and probably in Bass Strait.