An extremely bright fireball was seen over Bangkok, Thailand this morning (Sep. 7, 2015) at about 08:40 local time (0:40 UTC). Many witnesses saw and heard it, and it left a vapor trail as well.
The video is impressive (the meteor comes in at 30 seconds):
The first thing I noticed was that it was moving extremely rapidly, and went from just being visible to flaring hugely in just over two seconds.
If you look at the shadows, and note that sunrise is at about 06:00 this time of year, then you can see the camera is facing roughly west. That means the meteor appeared also to be moving roughly west. It's possible it may have been in a retrograde orbit, circling the Sun in the opposite direction as Earth, otherwise it would’ve moved to the east. I’m guessing here, but that would explain the rapid motion; it hit us head-on, adding its orbital velocity to our own.
I’ll add that another video makes the direction less clear, and geometry can be difficult to deduce without more information. So don’t draw too many conclusions on this just yet. Hopefully we’ll be hearing more about this.
The flares of brightness are probably due to the solid body breaking up due to the huge pressure as it rammed through our air. As it falls apart the smaller pieces have more surface area, so there’s more heating, and it happens so rapidly that you get those bursts of brightness.
Again, note how it goes from first being seen to a very rapid flare in brightness. It may have had a steep angle of descent, but it’s hard to tell from these videos. If the locations of the cameras are well known, then the 3D path of the meteoroid (the solid part) can be determined.
This is different than what happened over Chelyabinsk, Russia, in 2013. That one was prograde, moving in the same direction as Earth, and appeared to have a much slower motion across the sky. Witnesses said the Chelyabinsk meteor outshone the Sun, and the meteoroid in that case was 19 meters across. This Bangkok rock must have been much smaller, because it didn’t get nearly as bright. The brightness depends mostly on the mass of the rock and its velocity, and in this case it was hauling. So it must have been far smaller than the Russian asteroid.
I’ll add that the Chelyabinsk rock did break apart and underwent multiple flares, though, raining debris down. This one may leave meteorites behind as well, but it’s hard to say.
I haven’t heard any followup on this yet, so I don’t know any more about it. As dramatic as it was I don’t think it was dangerous; these objects tend to burn up many dozens of kilometers above the ground (and any small meteorites that might fall from there wouldn't be moving very rapidly when they hit; you wouldn't want one to bean you on the head, but it also wouldn't be like from a Michael Bay movie, either). Chelyabinsk was bad because of the shock wave, which was so powerful it shook buildings and shattered windows. This one was much smaller. Events like this happen a few times times a year. But when they happen over populated areas we get these great videos!
If I hear more, or find more video, I’ll post an update. My thanks to Cod Satrusayang for the tip!
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