AMS Fireball Stats Analysis released

The American Meteor Society has just published a statistical analysis of fireball events reported to the society since 2005 which can be found here: HTML format or PDF format.

With all the talk about fireballs on ATS (and other forums) about an apparent "increase in the frequency of fireballs" recently, this analysis could not have come soon enough.

Here are a few paragraphs from the report:

As the graph below illustrates, the number of reports filed with the AMS has been increasing over the last few years. The level of traffic on the site, the popularity of the site and improvements to the software are all contributing to more reports being filed. More people are able to find the site and more easily complete the report application. These factors contribute to an increase in witness reports being filed with the AMS.

3.
Circumstances effecting the number of reports and events collected by the AMS

There are circumstances affecting the data collected by the AMS that should be understood to prevent misinterpretation regarding the change of fireballs reported.

Things to note:

1) From January 2005 through December 2010 the AMS fireball reports system was based on the same data collection form and process created by Bob Lunsford in 2005.

2) In December 2010 the AMS fireball reporting system was upgraded to a database google maps system developed by Mike Hankey and Associates.

3) The new software made it much easier for witnesses to file reports and resulted in more witnesses successfully reporting events.

4) Internet traffic on the AMS site has increased since 2005. In current years, more people are connected with mobile devices, laptops and computers than ever before. This leads to more people reporting fireballs.

5) At least one huge event with over 100+ reports in 2009 was space trash, and there was at least 1 space trash event for 2012. The graph of 100+ events has not been adjusted to account for space trash.

6) A percentage of reports received are cloud contrails, planes, sun dogs or phenomenon other than fireball meteors. These reports are deleted when detected and generally tend to be events reported by only one witness.

7) In November 2012, the AMS fireball reporting software was upgraded again and this upgrade resulted in an immediate increase of reports received. It is believed that improvements to the user interface lessened the amount of form abandonment and other training issues that may have kept witnesses from successfully logging events on the previous version.

The AMS fireball reporting tool, while a useful service to the public and scientific community, is not a controlled scientific environment that one can use to reach conclusions about the frequency of fireballs. The AMS in no way suggests that the frequency of fireballs has increased or is increasing. This is not to say that fireball and bolide rates are not increasing, they may in fact be increasing, we simply cannot prove this with the AMS reports alone. We can only conclude from the data collected that more users are submitting fireball reports. It is understood that the rates of fireballs will increase and decrease year to year, but in order to answer the question “Have the rates of fireballs been increasing lately?” a more comprehensive study is needed.

Analysis of DOD & DOE Bolide Data

As documented in, The Flux of small near-Earth objects colliding with Earth (Letters to Nature–vol420, 2002), the United States Department of Defense and Department of Energy operate space-based systems that are capable of detecting bolide events across the entire globe. From the period of February 1994 to September 2002 bolide data from this system was analyzed, and based on that analysis these conclusions were made:

We estimate that the Earth is on average struck annually by an object of energy, 5 kton (with a possible range of 2–10 kton), and struck each month by an object with 0.3 kton of energy. Every ten years, an object of energy,50 kton strikes Earth.

Letters to Nature–The Flux of small near-Earth objects colliding with Earth, P. Brown, R.E. Spalding, D.O. ReVelle, E. Tagllaferri & S.P. Worden NATURE | VOL 420 | 21 NOVEMBER 2002

Re-executing this 2002 study using the DOD bolide reports from 2003-2012 would provide definitive insight into the recent perceived increase in fireball rates. Another benefit resulting from this study would be the development of a worldwide large-bolide frequency table covering a 20-year time period. It appears the DOD agrees more study of fireballs is needed and they have recently stated they will re-enable the sharing of bolide data with the public, as reported by Leonard David at space.com on February 26th, 2013.

On March 14th NASA announced the release of a Fireball and Bolide website where the analyzed results of the DOD data will be published. The AMS hopes NASA will give attention to the most significant bolide events that were recorded over the USA and reported to the AMS over the last five years. The release of bolide data relating to these events will help the AMS calibrate the reporting of our system so that future analysis will be more accurate. We will also be able to use this data to better understand past events and reach more meaningful conclusions about the size, locations and origins of these asteroids and meteoroids that have already struck Earth.

Conclusion

Since 2005, the AMS fireball report system has logged over 17,000 reports, identified more than 8,000 unique fireball events and been successfully used for different purposes by the scientific community and various government agencies including NASA, the Coast Guard, and the Air Force. Several meteorite recoveries have occurred in part due to the data collected by the AMS and the AMS fireball reports have assisted meteor and meteorite research at NASA Ames and other NASA offices. The re-entry of satellites and space debris has been confirmed by AMS reports. The Coast Guard has also used the AMS reports to vet calls about crashed airplanes off the coast of Florida (which later turn out to be fireball meteors). The AMS continues to improve the systems that collect and analyze the fireball report data. We have developed trajectory analysis programs that automatically determine the flight path of fireball meteors (within a margin of error) and we are in the process of creating orbital analysis programs for the improvement of meteorite recovery and meteor research. The AMS fireball log is the most comprehensive set of public data regarding bolide and fireball events that have taken place over the United States since 2005.

While the AMS fireball log has many uses and benefits, based on the AMS reports alone it is not possible to make conclusions about an increase or decrease in fireball/bolide events from year to year. However, the data shows that reports submitted to the society have been increasing and a significant increase in large events was specifically noticed in 2012. This warrants further study.

I know it will disappoint some members on here who touted the increase in reports of fireballs as supporting evidence for an increase in the frequency of fireballs, but as some of us have been saying all along, an increase in the number of reports collected by the AMS does not necessarily mean that actual fireball rates are increasing, although as pointed out by the analysis, that might be the case.

Large events in 2012 were significantly up according to the conclusion. This actually shows an increase and says it should be investigated more. Sounds like NASA has been imputing their stuff for years and so have other agencies.

aaaahhhhh good news for all human kind

reply to post by FireballStorm

Thanks FireballStorm for putting in the work.

4) Internet traffic on the AMS site has increased since 2005. In current years, more people are connected with mobile devices, laptops and computers than ever before. This leads to more people reporting fireballs.

Add in the "Me Too" factor and you get quantum leaps of faith, ignorance and embellishment. We all want to be part of it and with the internet , we can (who's going to know otherwise).

The report is not scientific as there is no way to determine the frequency of the meteors based on recorded self reports that did not query the entire population

Further the data regarding what meteorites have been found is incomplete as there are numerous underdiscovered meteorites buried underground because of time, world wide.

That all great and everything but, all of the statistics in the world aren't going to mean jack squat when one of these things comes crashing down in a major metropolitan area killing thousands and injuring tens of thousands.

I expect that WHEN this happens, there will be no shortage of internet shills getting on here and trying so desperately to convince everyone that everything is normal and there is statistically no increase in fireballs in the sky.

Sometimes it takes something of this magnitude to shake people out of their self induced coma and force them to deal with an uncomfortable reality.

Sometimes, it takes even more.

Originally posted by GeneralChaos
That all great and everything but, all of the statistics in the world aren't going to mean jack squat when one of these things comes crashing down in a major metropolitan area killing thousands and injuring tens of thousands.

I expect that WHEN this happens, there will be no shortage of internet shills getting on here and trying so desperately to convince everyone that everything is normal and there is statistically no increase in fireballs in the sky.

Sometimes it takes something of this magnitude to shake people out of their self induced coma and force them to deal with an uncomfortable reality.

Sometimes, it takes even more.

Look up something called SELF REPORT as something which causes BIAS in a study.

Let me help you. If there are only 10 people in a room and a spark comes out of the wall probably no one will notice.

You put 100 people in the room and someone notices.

You get it now?

Originally posted by LastStarfighter
The report is not scientific as there is no way to determine the frequency of the meteors based on recorded self reports that did not query the entire population

Did you not read the whole analysis?

The conclusion was that the increase in reports is not evidence in itself of an actual increase in fireballs, and further study needs to be done to get a valid answer.

Originally posted by LastStarfighter
Further the data regarding what meteorites have been found is incomplete as there are numerous underdiscovered meteorites buried underground because of time, world wide.

This analysis does not even talk about meteorites. It's purely about fireballs.

reply to post by GeneralChaos


What would you propose we do then? Run around in circles screaming "the sky is falling, the sky is falling!"?

And when would you draw the line after which things stopped being "normal"?

Have a look at this list of meteor air bursts - it might help you decide!

Well this shows me something. It shows me that there are others predominant in the field that seem to notice an uptick in these events. Maybe they can't make a conclusion based on exact evidence but they are at least investigating it instead of ignoring it. People who say there is no evidence without actually looking at what is out there are one of the reasons this world is so messed up. This investigation into it is good. Then when the evidence is in the nay sayers will say, well now it is proven so we can now say it is real. By that time they will be reducing again and they will be saying they are increasing.:shk:

reply to post by rickymouse


Yes, it is certainly not being ignored. There are many researchers trying to figure out what is going on right now, and I think everyone is eager to get an answer. There is no point rushing into it and coming up with the wrong answer - indeed, I think that would do much more harm than good!