The flash of greenish-blue light seen in the sky in several northern provinces late on Tuesday afternoon, which was followed by the sound of a loud explosion, was possibly a bolide, the National Astronomical Research Institute (Narit) said yesterday.
A bolide is an extremely bright meteor, especially one that explodes in the atmosphere.
The light and the explosion were observed in Chiang Mai, Lamphun, Phayao, Mae Hong Son and Lampang, said Suparerk Karuehanon, head of the academic support section of Narit.
The light was seen speeding from the western side to the eastern side of the sky before the explosion was heard and the impact of the explosion was felt, he said, adding no damage has been reported so far.
Citing a video clip posted on social media by Alisa Seya, a Phrao district resident in Chiang Mai who had captured what appeared to be a flying fireball in the sky, Mr Suparerk said it was likely to be a bolide.
Small meteors usually burn up within the atmosphere, about 80 to 120 kilometres from the Earth's surface, which explains why explosions of these pieces of rock from outer space are not normally heard, he said.
On some occasions, shooting stars cause a sonic boom, a sound associated with shock waves created when an object travels through the air faster than the speed of sound, he said.
This is consistent with Tuesday's incident, in which the speeding light was followed by the explosion, he said.
He said no conclusion had been made as to whether what was seen and heard in the North was a bolide.