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Thanks Alex. For completeness I attach the chart for 200105 – which I should have done in the first place. My own feeling is that it does not show anything exceptional. I turned it off at 1200 as I needed the radio for something else!
Best wishes Colin
Hi Alex
I monitored the Quadrantids on 200103-5 by forward scatter using the BRAMS beacon. From here it has a bearing of 137 deg. and range 600km.
The attached chart for Jan 03 shows a gentle rise after 2200 as the radiant climbed in the NE sky. The chart for the following 24h period of Jan 04 shows an odd drop in numbers between 0045 – 0145 followed by a steep rise from 0200 when the azimuth of the radiant was at around 47 deg – meaning that a high proportion of ionised trails lay normal to the line between transmitter and receiver, the ideal situation. Numbers held to a steady maximum centred on around 0400 before declining after 0515 to a low at about 0800 – when the azimuths of the radiant and BRAMS temporarily coincided, leading to a reduction in detected events. Then numbers slowly increased again to a second but slightly lower peak at around 1320. There was an abrupt drop at 1330 and by 2030 the radiant was on the northern horizon at an altitude of about 12 deg. Meteor numbers were then very low… they were probably mostly sporadics. The following morning to 1200 showed only comparatively low levels of activity in a normal diurnal curve.
At the time predicted for the visual maximum by the Nemetode analysis (0445) levels are certainly high. On the other hand the IMO predicted a short-lived maximum on Jan 04 at 0820 and the BAA on Jan 04 at 0900. Perhaps the rise and fall of a radio maximum at around 0830 was detected here – but the peak was lost to the ‘hollowing-out’ of the curve caused by the null detection point falling at the same time. This would be a long maximum, abruptly ended.
In all this I haven’t taken account of the changing altitude of the radiant as the maths is a bit complicated. I will have to think about that one!
Colin
John B
Thank you. On and off about five years. But only a couple of months using BRAMS and my Icom R75 – which by the way I now prefer to GRAVES and the Fun Cube Dongle! I do intend to look back over my old data and if I find anything comparable will post it.
Colin
Histogram of detected
events 0000-0640 – 10m bins. Steady rise to maximum 0450-0500 then rapid fall 0510-0520Colin
Hello. Using the BRAMS radar in Belgium (49.970MHz) I detected here in York a ninefold increase in rate beginning at 0450 and lasting just a few minutes – ie rate jumped from one event every three minutes to three events a minute. Will post charts and more precise data later today but here are a couple of screen captures
.Colin
Hello Trevor
Interested to see your results. I attach my own (using 3-el Yagi, FCDP+, Spectrum Lab) covering the same period in 30m intervals. You will see that all three of us saw the same small uplift at around 2am.
Of course there are at least three other factors to take into account: the diurnal variation due to the rotation of the earth, the changing altitude of the radiant, and above all the changing geometry of the radiant-radar-our receivers that William mentioned. Nevertheless that 2am rise gives pause for thought. I have a lot more work to do on my data yet but will post more when I have it.
