A summary of the activity of the CAMS BeNeLux network during the month of April 2018 is presented. The month started with mainly cold cloudy weather which improved just in time with a stable favorable situation to cover the April Lyrid activity period. 11328 meteors were recorded, 5529 of which proved multiple station, or 49%. In total 1929 orbits were collected during this month, including 203 orbits identified as Lyrid orbits.

 

1 Introduction

First two weeks of April 2018 were characterized by the same unstable and unfavorable weather pattern which continued since the last week of March. Most of the nights remained cloudy with no more than clear gaps. With only two nights with partial clear sky at most stations resulting in a reasonable number of over 100 orbits, April 2018 seemed to become another disappointing month. Luckily, by mid-April, the cold mainly overcast weather ended. The sudden weather improvement brought much warmer and dry weather with excellent transparent sky. The poor start of April was compensated by a week-long favorable weather covering most of the activity period of the April Lyrid meteor shower, most nights were clear from 16 until 23 April.

2 April 2018 statistics

CAMS BeNeLux collected 11328 meteors of which 5529 or 49% were multi-station, good for 1929 orbits. This is the highest number of orbits ever for the month of April. The statistics of April 2018 are compared in Figure 1 and Table 1 with the same month in previous years since the start of CAMS BeNeLux in 2012.

A new extra camera, 328, was added by Martin Breukers at his CAMS station in Hengelo, the Netherlands. The CAMS station Oostkapelle, the Netherlands, with 8 cameras, a cornerstone of the CAMS network, remained out of service during April for renovation works. The CAMS station at Alphen a/d Rijn, the Netherlands, solved a problem with the time synchronization which was at the origin of a failure to identify multiple station events during almost 4 weeks in March. CAMS station Texel, the Netherlands, was down for 11 nights due to technical problems. Finally, CAMS station Terschelling encountered a problem with the time synchronization, producing no multiple station events since 26 March until 22 April, missing most of the favorable Lyrid activity. The unavailability of both most northern CAMS stations, Terschelling and Texel, reduced the chances for capturing multiple station meteors for the remaining cameras pointed at the northern region of the network.

The success of April 2018 was mainly due to the exceptional good weather during the week of the April Lyrid activity. The CAMS network had to do without the 8 cameras of the strategic important station Oostkapelle, this way April was covered with 83 cameras at best, against 91 operational cameras in March. Thanks to AutoCAMS 59 cameras were all nights operational, more than ever before. This way on average 88.3% of the available cameras were active, only February 2018 had a better score with 89.8%.

 

Figure 1 – Comparing April 2018 to previous months of April in the CAMS BeNeLux history. The blue bars represent the number of orbits, the red bars the maximum number of cameras running in a single night and the yellow bar the average number of cameras running per night.

 

Table 1 – April 2018 compared to previous months of April.

Year Nights Orbits Stations Max. Cams Min Camas Mean Cams
2012 6 11 4 2 2.0
2013 19 140 9 10 6.5
2014 19 421 12 29 18.8
2015 27 1212 15 43 33.9
2016 26 971 17 50 15 37.0
2017 28 1235 20 60 32 48.2
2018 27 1929 21 83 59 73.3
Total 152 5919

 

As many as 203 orbits of the 1929 orbits collected in April were identified as Lyrids. A detailed report on the Lyrid activity 2018 has been published by Johannink and Roggemans (2018). The exceptional circumstances during the 2018 Lyrids allowed extensive visual observations too (Miskotte, 2018a, 2018b).

During the Lyrid meteor shower activity, several orbits caught attention identified as ζ-Cygnids (ZCY–040). The presence of these orbits in the 2018 data inspired a detailed case study on this shower and the probably associated shower, the April ρ-Cygnids (ARC–348) (Roggemans and Campell-Burns, 2018).

 

3 Conclusion

April 2018 started with poor and cold weather until a sudden weather improvement brought much warmer and dry weather, well timed to cover most of the Lyrid activity. The favorable Lyrid activity period and the many extra cameras available compared to previous years explain the record number of orbits collected for this month of April.

 

Acknowledgment

Many thanks to all participants in the CAMS BeNeLux network for their dedicated efforts. Thanks to Carl Johannink for providing all the data on which this report is based. The CAMS BeNeLux team was operated by the following volunteers during the month of April 2018:

Hans Betlem (Leiden, CAMS 371, 372 and 373), Felix Bettonvil (Utrecht, CAMS 376 and 377) , Jean-Marie Biets (Wilderen, CAMS 380, 381 and 382), Martin Breukers (Hengelo, CAMS 320, 321, 322, 323, 324, 325, 326, 327 and 328), Bart Dessoy (Zoersel, CAMS 397, 398, 804, 805 and 806), Franky Dubois (Langemark, CAMS 386), Jean-Paul Dumoulin / Christian Wanlin (Grapfontaine, CAMS 814 and 815), Luc Gobin (Mechelen, CAMS 390, 391, 807 and 808), Robert Haas (Alphen aan de Rijn, CAMS 3160, 3161, 3162, 3163, 3164, 3165, 3166 and 3167), Robert Haas / Edwin van Dijk (Burlage, CAMS 801, 802, 821 and 822), Robert Haas (Texel, CAMS 810, 811, 812 and 813), Carl Johannink (Gronau, CAMS 311, 312, 313, 314, 315, 316, 317 and 318), Hervé Lamy (Dourbes / Ukkel, CAMS 394 and 395/ 393), Koen Miskotte (Ermelo, CAMS 351, 352, 353 and 354), Piet Neels (Ooltgensplaat, CAMS 340, 341, 342, 343, 344 and 345, 349, 840), Piet Neels (Terschelling, CAMS 841, 842, 843 and 844), Tim Polfliet (Gent, CAMS 396), Steve Rau (Zillebeke, CAMS 3850 and 3852), Paul Roggemans (Mechelen, CAMS 383, 384, 388, 389, 399 and 809), Hans Schremmer (Niederkruechten, CAMS 803) and Erwin van Ballegoij (CAMS 347 and 348).

References

Johannink C. and Roggemans P. (2018). “CAMS BeNeLux: results April 2018”. eMetN, 3, 192–194.

Miskotte K. (2018a). “Lyrid 2018 observations from Ermelo, the Netherlands”. eMetN, 3, 195–197.

Miskotte K. (2018b). “Lyrids 2018: an analysis”. eMetN, 3, 204–206.

Roggemans P. and Campell-Burns P. (2018). “Zeta Cygnids (ZCY) and April rho Cygnids (ARC) two filaments of a single meteor stream?”. eMetN, 3, 175–184.