An overview of the radio observations during April 2021 is given.
The graphs show both the daily totals (Figure 1) and the hourly numbers (Figure 2) of “all” reflections counted automatically, and of manually counted “overdense” reflections, overdense reflections longer than 10 seconds and longer than 1 minute, as observed here at Kampenhout (BE) on the frequency of our VVS-beacon (49.99 MHz) during the month of April 2021.
The hourly numbers, for echoes shorter than 1 minute, are weighted averages derived from:
This month quite severe local interference or unidentified noise sometimes disturbed the registrations, while weak lightning activity was recorded on 3 days. Most of this unwanted interference was manually corrected before the automatic counting.
As expected meteor activity remained relatively low in the first half of the month, but as from April 19th the Lyrids nicely showed up. As expected, they peaked on April 23rd, with quite numerous overdense reflections shorter than 1 minute.
During this month, 4 reflections longer than 1 minute were recorded. A selection of striking or strong reflections is attached. (Figures 3 to 8).
If you are interested in the actual figures, or in plots showing the observations as related to the solar longitude (J2000) rather than to the calendar date, I can send you the underlying Excel files and/or plots. Please send me an e-mail; felix.verbelen at skynet.be.