Satgen 198 1993 Quadrantids Summary by GM4IHJ 9th Jan 93 BID of this msg is SGEN198 Please use this BID if you retransmit this msg Each year Meteor Scatter enthusiasts get a special New Year treat - the Quadrantids Meteor Shower which occurs on Jan 3rd or 4th. This year it peaked around 1330ut on 3rd Jan, and it was a superb peak. Astronomers rate this shower as "Intense but short duration" however this observer has long been of the view that it is time we Radio Experimenters and Communicators ignored the limited view point of the visual observers and concentrated more on understanding and preparing for the quite distinct double pattern of this shower. The following summarises the events of the 93 shower from the Radio point of view and assesses how best we can use it for communications. With peak activity due at 1300 ut 3rd Jan. This observer first monitored the shower at 2000 ut on 2nd of Jan to see if anything was present at this time predicted for the peak by RSGB Magazine RadCom. In fact there was only a slight increase in the background activity as recorded by checking 2m beacons and a network of 5 high powered European TV carriers around 62.2498 MHz. At 0700 on the 3rd the weak background pings were showing more activity with some longer stronger pings at times, but nothing really strong as I listened up to 1130 ut at which time the longer pings were much more frequent but not yet overwhelming. Gradually as the clock moved up to 1330 ut the weak and the strong pings increased until at 1330 ut they could be described as wall to wall virtually continuous. This very strong peak continued until just before 1450 ut when the weaker shorter pings started to vanish . The longer stronger pings meanwhile continued to hold up well even at 1600 when almost all the weak pings had gone. Then slowly as we moved up towards 2100 ut the number of long pings began to decline although they still came through now and again as IHJ went to bed. Summary and Analysis. Clearly the 93 Quadrantids was a super shower, although visually it was a complete wash out peaking in daylight and fading invisibly above 10/10 cloud. From the radio point of view we got 14 hours consisting of two highly sorted streams , firstly the small particles and then distinctly separate and later , the big particles. This is no surprise. Donald Yeomans of JPL has demonstrated that many Comet/Meteor streams are gradually sorted by the Sun , so that we as in this case cross the stream of small particles first, then the big particles later. In future we must be aware of this. The time is long past when we should rely on old visual predictions which are inherently incapable of providing this kind of detail. Relying on a method which is roughly a thousand times less sensitive than the radio method even when visibility is good and peak occurs at night, is crazy, as witnessed by RadCom Jan93 p16 giving a totally misleading prediction of radio shower peak , which could be seen to be wrong by anyone who checked the actual 90/91/92 radio peak time sequence. RSGB Space Radio Handbook p212 has the correct timing .So please book your 1994 Quadrantids small pings 1300 to 2000, big pings 1800 to 2400 ut 3 Jan 94 , with main peak around 1900 ut. All Satgen bulletin files Disc1 1 to 99, disc2 100 to 198 are available to UK/EI stations on receipt 2 formatted DD DS 3.5 ins discs ( NOTE NOT HD ) plus suitable return package and postage. Other Stations should send request+ address to IHJ by packet. Discs will be sent free provided please ,you make small donation to YOUR OWN LOCAL AMSAT. 73 de GM4IHJ @ GB7SAN