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Sat, 24 May 2014 - Camelopardalids disappoint observers

Hopes for a strong meteor shower due to the Earth's encounter with dust trails left behind a century ago by comet 209P/LINEAR seem to have been dashed.

 
With the most favourable dust trail encounters occurring between 06:50 and 07:30 UT, the circumstances favoured observers in the United States and southern Canada. Many media reports mentioned likely peak rates of around 200 per hour and some more sensationalised reports even promised a meteor storm (ZHR > 1000). However, there was always considerable uncertainty in the likely rates given that the comet wasn't discovered until 2004. The dust trails that would pass closest to the Earth in 2014 were ejected over a century earlier and therefore we had no knowledge as to how active or inactive the comet might have been at that time. 
 
In the UK it would be daylight at the time of the predicted peak and the best that could be hoped for would be to catch one or two early Camelopardalids just before dawn. In the event, with a low pressure area circulating over the UK, cloud breaks were few and far between and those observers who did get short cloud breaks reported seeing little or nothing.
 
Bill Ward was clouded out in Glasgow, but monitored meteor activity at radio frequencies and has reported that the observed meteor rates barely increased, if at all, above the normal sporadic background level around the time of the predicted peaks. Bill has posted a time lapse of spectrogram frames on-line at http://www.youtube.com/watch?v=perEWchykNU&feature=youtu.be
 
Based on Twitter posts and on emails to the meteorobs list, it seems that most observers in North America were left disappointed and let down. Indeed, there seemed to be more tweets containing links to observing quides and live feeds than there were from people reporting seeing Camelopardalids. Some observers tweeted that they did at least enjoy seeing one or two bright Camelopardalids. In general, however, it seems that most observers with dark skies only saw a few Camelopardalids per hour at best.
 
Nevertheless, it is certain that the meteor shower did occur. Video monitoring by experienced observers has confirmed this, as have the paths and slow speeds of Camelopardalids described by visual observers. The problem was that observed visual rates were well below what people had been led to expect by the media.
 
There was brief excitement in the late afternoon of the 24th when the Canadian Meteor Orbit Radar (CMOR) website http://fireballs.ndc.nasa.gov/cmor-radiants/ suddenly started shown a strong signal from the location of the Camelopardalid radiant. However, it was subsequently revealed that the site only updates the displayed intensity data retrospectively once a day ... and so it was only showing that the Camelopardalids had been quite active in the preceding 24 hours.
 
More detailed analyses to reveal peak ZHRs and the timing of any peaks will have to wait for the reporting of more detailed observations. However, the IMO has published a provisional activity graph based on the early data received. This can be found at : http://imo.net/live/cameleopardalids2014/#overview and as of the evening of May 24th was indicating a peak ZHR well below that typically seen from showers such as the Perseids and Geminids and possibly more in line with that of the Lyrids.
 
Bill Ward has carried out an initial analysis of his radio counts an the results are shown in the graph below. Bill notes that the graph does show peaks whose times roughly coincide with the times predicted by David Asher for the close encounters with the 22-rev and 47-rev dust trails, but cautions that radio observing is essentially blind to the meteor identity. What percentage of any given count are actually Camelopardalids and what are not is impossible to say.
 

Added by: Tracie Heywood