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.
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.
In December 2010 the AMS fireball reporting system was upgraded to a database google maps system developed by Mike Hankey and company.
The new software made it much easier for witnesses to file reports and resulted in more witnesses successfully reporting events.
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.
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.
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.
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.
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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. A pairing of DOD bolide data with AMS event data would prove useful to the scientific research of meteors striking Earth. In addition, the AMS reports identify the date, time, location and relative size of significant fireball events. This information could be useful in pinpointing events inside the DOD’s data sets. The AMS makes all report data available through our website and encourages the use of our data.
http://www.amsmeteors.org/fireballs/fireball-tracking-system-analysis/