Fireball tally from American Meteor Society

Aeneas

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Reading through Laura's latest book that came out in Sept 2012 called "The Apocalypse", I found the list of sightings very interesting and the tally from the American Meteor Society worth keeping a tap on as time progresses.

Laura said:
The American Meteor Society has collected American fireballs reports from 2005 to the present. To give an idea of just how many fireball sightings there are just in the US that aren't necessarily reported in the media (ie. those that make up the bulk of the SOTT archives), here are their yearly totals:

466 in 2005
515 in 2006
537 in 2007
727 in 2008
693 in 2009
948 in 2010
1629 in 2011
795 until June 6,2012
The tally for 2012 has now surpassed 2011 and stands today the 6th of November at 1645.

The "extremely rare once in a lifetime events" are now becoming almost a daily occurrence. Foreboding I would say.
 
Aeneas said:
The tally for 2012 has now surpassed 2011 and stands today the 6th of November at 1645.

Yep, by this time last year, according to AMS, there were 1300 reports...
 
Aeneas said:
Reading through Laura's latest book that came out in Sept 2012 called "The Apocalypse", I found the list of sightings very interesting and the tally from the American Meteor Society worth keeping a tap on as time progresses.

Laura said:
The American Meteor Society has collected American fireballs reports from 2005 to the present. To give an idea of just how many fireball sightings there are just in the US that aren't necessarily reported in the media (ie. those that make up the bulk of the SOTT archives), here are their yearly totals:

466 in 2005
515 in 2006
537 in 2007
727 in 2008
693 in 2009
948 in 2010
1629 in 2011
795 until June 6,2012
The tally for 2012 has now surpassed 2011 and stands today the 6th of November at 1645.

The "extremely rare once in a lifetime events" are now becoming almost a daily occurrence. Foreboding I would say.

The updated number of 2012 (through to Nov 5) is 1645.

So that's about 2 per day until 2011, 4.4/d in 2011, and 2012 so far is averaging 5.3/day (same number if you use the earlier June data).
 
Yee Haw. Ride 'em cowboy and cowgirls.!.!.!
The show may have begun! At work here, I'm blocked off YouTube. I keep thinking of a song maybe called: Raindrops keep falling on my head..
 
Al Today said:
Yee Haw. Ride 'em cowboy and cowgirls.!.!.!
The show may have begun! At work here, I'm blocked off YouTube. I keep thinking of a song maybe called: Raindrops keep falling on my head..
The evil mess the world's in today, we need a good old-fashioned cataclysm to clean things up.
Bring it on!
 
psychegram said:
The updated number of 2012 (through to Nov 5) is 1645.

So that's about 2 per day until 2011, 4.4/d in 2011, and 2012 so far is averaging 5.3/day (same number if you use the earlier June data).

And we still have almost 2 months left to go 'til 2013. I wonder if we'll get a really big fireworks show to bring in the new year.
 
Andromeda said:
psychegram said:
The updated number of 2012 (through to Nov 5) is 1645.

So that's about 2 per day until 2011, 4.4/d in 2011, and 2012 so far is averaging 5.3/day (same number if you use the earlier June data).

And we still have almost 2 months left to go 'til 2013. I wonder if we'll get a really big fireworks show to bring in the new year.

Good question! Not to mention the possibility of another villainy being perpretated by our dear leaders. Meanwhile, I can't wait to see how everything will go following the elections, especially in regards to the masses. The whole thing smells funny. Sandy, media-crazyness, V-Day, elections, 2012 hysteria etc. As a matter of fact, I also wonder what's going on with HAARP these days...

Oh man, the New-Agers must be quite anxious. I bet they are stockpiling light and love in jars or something.

*Sigh*

I guess that "wait and see" is getting closer and closer to "see" alone.

Anyhow, will be seated with you guys! :cool2:

Peace.
 
The log of fireball sightings reported by or to the American Meteor Society is located on http://www.amsmeteors.org/fireballs/fireball-report/ There is a function that allows one to select for each year those incidents that was accompanied by sound, whether delayed or concurrent, and or fragmentation. The following table shows the results:

Breakdown of fireball incidents according to associated events

Year With fragmentation With sound With both All reported fireballs
2012 as of Nov 6th 520 202 109 1655
2011 514 181 102 1629
2010 50 15 7 948
2009 1 1 0 693
2008 0 0 0 727
2007 1 1 0 537
2006 0 0 0 515
2005 0 ?46? 0 463


The number of 46 sightings with sound reported for 2005 is not confirmed the way I read the table, because the letter n/a are noted for each of these categories, therefore I do not understand what is going on in this case.

If one compares the numbers for each year, one notices that the ratio between observed fireballs and fireballs accompanied with sound phenomena and or fragmentation has increased dramatically. This reflects, it seem to me, that the size of the incoming objects has grown.

On the one hand, the numbers might reflect an increased interest and therefore be a result of more open eyes and more reports. On the other hand there would not be interest if nothing happened. If I have to be critical of the number of sightings I think that spectacular sightings with sound and or fragmentation are more reliable in the sense that they usually have more witnesses, although I admit that a single reliable witness also has weight.

In the table one notices that many more fireballs are associated with fragmentation than with sound. This may be a result of fragmentation occurring at altitudes where sound is not produced, or that incidents are observed at distances from where sounds do not reach. Also one may note that in the cases where sound is reported, mostly only few observers report it, which again may be explained by them being placed differently in relation to the event, with those being closer having a better chance of hearing sound.

If one compares the amount of fireballs observed with fragmentation to the number observed with both fragmentation and sound, it appears that about one fifth of the number observed with fragmentation also produces sound.

To find the number of fireballs that only produce sound but do not fragment, one subtracts the number of those that both fragment and produce sound from the total number of those that produce sound. For example 181-102 which gives us, for the year 2011, the number of 79 fireballs that only produced sound. It turns out that for the period of 2010-2012 roughly half of those that produced sound were not observed to fragment.

It appears to me that a daytime fireball might be able to fragment without this being clearly visible to an observer, because a small fragment may not have enough light to outshine the light from the sun. Another reason for apparent lack of fragmentation might be the angle under which the event is observed. It might also be possible that a fireball produces a sound, but no clearly observable light, either because the light was too faint, which would typically happen during daytime, or because it occurred out of view.

This small analysis has shown that the problem of fireballs taken from a qualitative perspective has become more serious than the mere numbers reveal.
 
Interesting analysis, Thorbiorn. To illustrate the point about sound and observers position, one can look at the big event on the 22nd of September, found here, which was reported by 162, 12 of whom reported a delayed sound and only 5 a concurrent sound. It was mentioned on SOTT at the times whether there were not possibly several fireballs, which then got lumped together as only one event. The puzzling thing is that one person in Norway heard a sound, where as all the others who heard a sound were in Britain. So perhaps there were more fireballs than one.
 
Aeneas said:
[...] To illustrate the point about sound and observers position, one can look at the big event on the 22nd of September, found here, which was reported by 162, 12 of whom reported a delayed sound and only 5 a concurrent sound. It was mentioned on SOTT at the times whether there were not possibly several fireballs, which then got lumped together as only one event. The puzzling thing is that one person in Norway heard a sound, where as all the others who heard a sound were in Britain. So perhaps there were more fireballs than one.

Good point, we might be able to separate two events by investigating the reports of sounds reported as associated with the fireballs and then look at the distance between them. As you suggest it a bit unlikely that sound from the same event should be heard in both Norway and England.

In general I gather that observing a fireball along with an associated sound phenomena would mean that the object is quite close to the observer, whereas a sound that follows later indicates that the distance to the event is further away.

The analogy is the the time lapse between a flash of lightening and the thunder, which when nearby follows shortly after the flash, whereas more time passes before the rumble is heard when the actual location of the strike is further away. And sometimes we only se the lightening as the sound is too far away to be heard. To explain a bit about the physics of sound the speed of sound in air can be approximated as:

V= 331.5 m/s + 0.6*(m/(s*degrees Celcius))*temperature in degrees Celcius,
(Formula adapted from _www.sengpielaudio.com/SpeedOfSoundPressure.pdf)

It therefor takes about 3 seconds per kilometer from the time we see a flash of lightening until we hear the sound. Or if we count 9 seconds from we se the flash until the sound arrives then it will correspond to a strike happening at about 3 km from us.

What I wonder about in the case of this event over Britain and Ireland, which I witnessed, is that if the whole show lasted maybe 30 seconds. How could sound then reach some observers if the object was that high up in the atmosphere as some calculations estimated. Lets say it broke up at an altitude of 55 km, which is the upper limit of the stratopause in the boundary area between the stratosphere and the mesosphere, where the air pressure is about 1/1000th of what it is at sealevel, then the sound, if it really originated or could be generated at that altitude, would take about 165 seconds to reach Earth. It seems to me that the object would be gone by the time the sound reached the observer. Add to this that one will usually see it at an angle. This fact should make the sound reach the observer after more than 165 seconds although this difference will be less for angles closer to vertical. And then we have not even taken into considerations the distortion caused by wind speeds. A sound that enters the jet steam no doubt gets a bit carried away :)

In other words if a sound is heard along with a fireball observation then it is probably close or big. A distinct loud sound would mean it is fairly close, or caused by a big object as was the case at the Tunguska event, and if it is only a low rumble, probably it is further away.
 
thorbiorn said:
Aeneas said:
[...] To illustrate the point about sound and observers position, one can look at the big event on the 22nd of September, found here, which was reported by 162, 12 of whom reported a delayed sound and only 5 a concurrent sound. It was mentioned on SOTT at the times whether there were not possibly several fireballs, which then got lumped together as only one event. The puzzling thing is that one person in Norway heard a sound, where as all the others who heard a sound were in Britain. So perhaps there were more fireballs than one.

Good point, we might be able to separate two events by investigating the reports of sounds reported as associated with the fireballs and then look at the distance between them. As you suggest it a bit unlikely that sound from the same event should be heard in both Norway and England.

In general I gather that observing a fireball along with an associated sound phenomena would mean that the object is quite close to the observer, whereas a sound that follows later indicates that the distance to the event is further away.

The analogy is the the time lapse between a flash of lightening and the thunder, which when nearby follows shortly after the flash, whereas more time passes before the rumble is heard when the actual location of the strike is further away. And sometimes we only se the lightening as the sound is too far away to be heard. To explain a bit about the physics of sound the speed of sound in air can be approximated as:

V= 331.5 m/s + 0.6*(m/(s*degrees Celcius))*temperature in degrees Celcius,
(Formula adapted from _www.sengpielaudio.com/SpeedOfSoundPressure.pdf)

It therefor takes about 3 seconds per kilometer from the time we see a flash of lightening until we hear the sound. Or if we count 9 seconds from we se the flash until the sound arrives then it will correspond to a strike happening at about 3 km from us.

What I wonder about in the case of this event over Britain and Ireland, which I witnessed, is that if the whole show lasted maybe 30 seconds. How could sound then reach some observers if the object was that high up in the atmosphere as some calculations estimated. Lets say it broke up at an altitude of 55 km, which is the upper limit of the stratopause in the boundary area between the stratosphere and the mesosphere, where the air pressure is about 1/1000th of what it is at sealevel, then the sound, if it really originated or could be generated at that altitude, would take about 165 seconds to reach Earth. It seems to me that the object would be gone by the time the sound reached the observer. Add to this that one will usually see it at an angle. This fact should make the sound reach the observer after more than 165 seconds although this difference will be less for angles closer to vertical. And then we have not even taken into considerations the distortion caused by wind speeds. A sound that enters the jet steam no doubt gets a bit carried away :)

In other words if a sound is heard along with a fireball observation then it is probably close or big. A distinct loud sound would mean it is fairly close, or caused by a big object as was the case at the Tunguska event, and if it is only a low rumble, probably it is further away.

Possibly it is only an assumption that the sound and the visual event are directly linked. That is to say, a sonic boom could be generated earlier/later in the sequence of the metor's entry into the atmosphere than the visible light produced. Someone correct me if I'm completely off base here, because I don't know enough about the physics of these events, it was just something that occurred to me.
 
Ben said:
Possibly it is only an assumption that the sound and the visual event are directly linked. That is to say, a sonic boom could be generated earlier/later in the sequence of the metor's entry into the atmosphere than the visible light produced. Someone correct me if I'm completely off base here, because I don't know enough about the physics of these events, it was just something that occurred to me.

It probably was an assumption. Some of the stages that might produce sound could be:
1. The moment of fragmentation where energy is released as the object explodes.
2. The moment the object enters or hits the atmosphere it may generate a sonic boom - or so I imagine.
3. As the object passes through the air. This would be similar to how a fast projectile generates sound.
4. If the object hits the surface.

Fragmentation can probably both be slow and fast. A high speed fragmentation should everything else equal, like the altitude where fragmentation occurs, the size, the incoming speed, the composition of the object, the incoming angle and degree of fragmentation generate more sound than a slow speed fragmentation.

The assumption I had about the object over Ireland the 21st of September was that the moment of fragmentation would generate sound. Sound was generated but as your doubt has made it clear, it could have happened at other stages. Maybe someone on the forum can tell us which stages in the life of an incoming fireball are more likely to generate sound, and for that matter, if the possibilities I mentioned are reasonable.
 
Andromeda said:
psychegram said:
The updated number of 2012 (through to Nov 5) is 1645.

So that's about 2 per day until 2011, 4.4/d in 2011, and 2012 so far is averaging 5.3/day (same number if you use the earlier June data).

And we still have almost 2 months left to go 'til 2013. I wonder if we'll get a really big fireworks show to bring in the new year.

Whether it qualifies as a firework is up for debate, but the tally up though to the 23rd of November is 1829, which makes it 184 since the last count here, which was through to the 5th of November. That makes it an average of 184events/18 days equals 10.2 events per day over the last 18 days. That is quite an increase imo.
 
thorbiorn said:
The following table shows the results:

Breakdown of fireball incidents according to associated events

Year With fragmentation With sound With both All reported fireballs
2012 as of Nov 6th 520 202 109 1655
2011 514 181 102 1629
2010 50 15 7 948
2009 1 1 0 693
2008 0 0 0 727
2007 1 1 0 537
2006 0 0 0 515
2005 0 ?46? 0 463


The final numbers for 2012 (as of today the 9th of January 2013) as recorded by the AMS is 2209 fireballs which is quite an increase compared to the 1629 in 2011 and the 948 in 2010. Things are heating up.
 
New update:

320 as of today.

320 / 45 days = 7.11/d

7.11 x 365 = app. 2595 at this trend.

So a few hundread more than last year for sure. And who knows, the trend may suddenly "shift gear" if you know what I mean. These last 24-48h have been quite special in terms of activity + the upcoming asteroid which may or may not interact with us. We'll know pretty soon!

Put your helmets on!
 
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