Video Observation of Meteors in the CEMeNt Network in November 2024

Meteor activity continued to rise in November, peaking with the strongest annual meteor shower, the December Geminids. The sporadic meteor background activity began to decrease towards its minimum, which typically occurs in spring months. Weather conditions in November were once again highly favorable, with at least one meteor captured on 24 nights at one of the stations of the CEMeNt (Central European Meteor Network). Observation conditions in November followed the trend of previous months, which were also very favorable. However, some lower-altitude stations began to experience the typical weather phenomenon of autumn and winter months – temperature inversions. This atmospheric effect had a negative impact on the number of paired meteors and, consequently, on the number of multi-station trajectories recorded.

The dominant meteor shower in the second half of the month was the Leonids (LEO). Throughout November, activity continued from the large complex of showers linked genetically to Comet 2P/Encke and related bodies, mostly classified as asteroids.

The activity of the Comet 2P/Encke complex peaked again in November (northern branch), with multi-station meteor trajectories recorded mainly from radiants in the constellations Taurus and Aries. The identified showers included tau Arietids (TAR – part of NTA, 56 trajectories), tau Taurids (TAT – part of NTA, 33 trajectories), delta Arietids (DAT – part of NTA, 29 trajectories), A2 Taurids (ATS – part of NTA, 24 trajectories), November eta Taurids (NET – part of NTA, 24 trajectories), and the northern Taurids themselves (NTA, 20 trajectories).

According to the IMO VMDB (International Meteor Organization Visual Meteor Database), the corrected maximum hourly rate of the northern Taurids this year reached 5.8 ± 1.3 meteors, with the peak occurring on November 5, 2024, at 12:24 UT. Multi-station trajectories were also recorded for the southern branch of the complex, including lambda Taurids (LTA – part of STA, 25 trajectories), f Taurids (FTR – part of STA, 25 trajectories), omega Taurids (FTA – part of STA, 25 trajectories), and the southern Taurids themselves (STA, 8 trajectories).

The primary meteor shower active in November was undoubtedly the Leonids (LEO). This year, the regular peak was expected on November 17 at 04:00 UT, with a corrected hourly rate of 15 to 20 meteors. Two secondary maxima were also predicted. The first on November 14 at 16:37 UT was expected to have a higher hourly frequency due to material ejected from Comet 55P/Tempel-Tuttle during its return in 1633, consisting of very fine particles (<1 mm). The second maximum was predicted for the night of November 19-20, between 23:53 and 00:54 UT. However, the material from the comet’s return in 1733 was distant from Earth’s orbit (-0.002 AU), suggesting lower rates for this secondary maximum. The IMO VMDB activity graph for the Leonids in 2024 is not yet available, but the CEMeNt network cameras recorded a total of 84 multi-station Leonid trajectories.

The last significant meteor shower peaking in November was the November Orionids (NOO). Their maximum was expected on November 28, with a corrected hourly rate of around 3 meteors. According to the IMO VMDB graph, the maximum corrected hourly rate of the November Orionids reached 5.6 ± 1.7 meteors this year, peaking on November 29, 2024, at 03:20 UT. However, the CEMeNt network cameras recorded a total of 39 multi-station trajectories for the November Orionids.

Fig. 1: Overall 2D projection of multi-station atmospheric trajectories recorded in the CEMeNt network in November 2024. Author: Jakub Koukal

Fig. 2: Radiants of shower and sporadic multi-station meteors recorded in the CEMeNt network in November 2024. A sinusoidal projection with an equatorial coordinate system is used for the display. Author: Jakub Koukal

In November (November 9, 2024), a new station was launched at the Baron Artur Kraus Observatory in Pardubice. The station is equipped with two cameras oriented NE and SE, which effectively complement the central part of the CEMeNt network, consisting of the stations in Valašské Meziříčí, Maruška, Štípa, and Vsetín. The station is equipped with systems using CMOS cameras with Sony Starvis IMX 290 LQR sensors, operating at a Full HD resolution of 1920 × 1080 px (2.1 MPx) and a frame rate of 30 fps. The high-aperture Starlight lens (f/0.95) with a fixed focal length (4 mm) used in this configuration provides a field of view of 89° (± 1) × 50°.

Fig. 3: Projection of multi-station meteor trajectories belonging to the Leonid (LEO) meteor shower within the Solar System. A total of 84 multi-station trajectories of the LEO meteor shower were recorded in November 2024. Author: Jakub Koukal

Fig. 4: Projection of multi-station meteor trajectories belonging to the northern Taurid (NTA) complex – tau Arietids (0630 TAR), tau Taurids (0634 TAT), delta Arietids (0631 DAT), A2 Taurids (0629 ATS), November eta Taurids (0632 NET), and the northern Taurids (0017 NTA) within the Solar System. A total of 187 multi-station trajectories of the NTA complex were recorded in November 2024. Author: Jakub Koukal

In November 2024, the cameras of the CEMeNt network recorded 13,431 single-station meteors, which resulted in the creation of 3,040 multi-station trajectories (Figures 1 and 2). As of today, observations from the outer perimeter stations, including Rokycany (CZ), Plzeň (CZ), Karlovy Vary (CZ), Blahová (SK), and Zvolenská Slatina (SK), have not been included in the analysis as their data processing is not yet complete.

The majority of the multi-station trajectories (Table 1) belong to the sporadic background (1,941 trajectories), followed by the Leonid meteor shower (84 trajectories, Figure 3) and other weaker meteor showers, including members of the northern branch of the Taurid complex (187 trajectories, Figure 4).

The number of single-station meteors (as well as multi-station trajectories) is historically the highest ever recorded within the CEMeNt network since its establishment in 2009. The pairing efficiency slightly decreased from 60.6% in October to 58.5% in November, primarily due to the onset of temperature inversion weather conditions at lower-altitude stations in the network. Two out of three single-station meteors were paired with a single-station meteor from another station, with the station-to-trajectory ratio increasing from 2.49 to 2.58.

A total of 76,348 single-station meteors have been recorded so far this year (as of November 30, 2024), resulting in the creation of 17,681 multi-station trajectories (Table 2, Figure 5).

Table 1: Overview of the number of multi-station meteor trajectories recorded in the CEMeNt network in November 2024. Author: Jakub Koukal

Table 2: Overview of the number of detected and paired meteors in 2024 at the CEMeNt network stations. Author: Jakub Koukal

Fig. 5: Graph of the number of detected meteors, multi-station trajectories, and meteor pairing efficiency in 2024 at the CEMeNt network stations. Author: Jakub Koukal

Fig. 8: Graph of the number of detected meteor spectra in 2024 captured by spectrographs at the Valašské Meziříčí Observatory. Author: Jakub Koukal

Fig. 6: A bright fireball captured by the VM NW camera at the Valašské Meziříčí station. The fireball belonged to the Leonid meteor shower, with the beginning of the ablation trajectory recorded at an altitude of 137.0 km and the end at 88.3 km above the Earth's surface. The fireball reached a maximum absolute brightness of -5.7 mag. Author: Valašské Meziříčí Observatory.

Fig. 7: A bright fireball captured at the Ždánice station (camera N). The fireball belonged to the Leonid meteor shower, with the beginning of the ablation trajectory recorded at an altitude of 137.0 km and the end at 88.3 km above the Earth's surface. The fireball reached a maximum absolute brightness of -5.7 mag. Author: Ždánice Observatory.

At the Valašské Meziříčí Observatory, there are currently three spectrographs equipped with monochromatic CMOS cameras PointGrey Grasshopper3 GS3-U3-32S4M-C (2048 × 1536 px). The actual resolution of the recorded meteor spectrum (first-order spectrum) averages 0.48 nm/px. These spectrographs are oriented in the SE, SW, and NE directions. In the NW direction, there is a spectrograph with a monochromatic CMOS camera QHY-III 178M (3072 × 2048 px), with an actual spectral resolution of approximately 0.35 nm/px for the first-order spectrum.

As part of a test setup, a spectrograph is also mounted in the W direction, using a monochromatic CMOS camera Basler acA3088-57uc (3072 × 2048 px), with an actual recorded spectral resolution of approximately 0.39 nm/px for the first-order spectrum.

In November, the spectrographs at the Valašské Meziříčí Observatory recorded 6 spectra from 4 individual fireballs (Figures 9 and 10). Throughout 2024, a total of 48 spectra of bright meteors (fireballs) from 35 individual fireballs have been recorded so far (Figure 8).

Fig. 9: Composite image of the spectrum of fireball 20241117_024954 SPO from the VM SPNW spectrograph (resolution 0.37 nm/px). Author: Valašské Meziříčí Observatory.

Fig. 10: Composite image of the spectrum of fireball 20241117_024954 SPO from the VM SPW spectrograph (resolution 0.41 nm/px). Author: Valašské Meziříčí Observatory.

Acknowledgements

Acknowledgements go to the companies DEZA, a.s. and CS CABOT, spol. s r.o., who contributed to the acquisition of equipment for the Full HD stations located at the Valašské Meziříčí Observatory and within the CEMeNt network. Special thanks also go to all partner observatories (Ždánice, Vsetín, Rokycany, Plzeň, Karlovy Vary, Partizánske, Kysucké Nové Mesto) and private station owners (Milan Čermák, Richard Kačerek, Jakub Kapuš, Tibor Csorgei, Vladimír Bahýl) for their support in the network’s activities and expansion.

Further gratitude is extended to all involved institutions for supporting the development and operations of the network.

The RPOS project (Development of a Cross-border Observation Network) was co-financed by the Small Projects Fund under the Interreg V-A Slovakia – Czech Republic 2014 – 2020 program, call code 5/FMP/11b, registration number CZ/FMP/11b/05/058.

The projects KOSOAP (Cooperating Network in the Field of Astronomical Professional-Observation Programs) and RPKS (Development of a Cross-border Cooperative Network for Professional Work and Education) were carried out by the observatories of Valašské Meziříčí (Czech Republic) and Kysucké Nové Mesto (Slovakia) in cooperation with the Society for Interplanetary Matter (SMPH). These projects were co-financed by the Microprojects Fund of the Cross-border Cooperation Operational Program Slovakia – Czech Republic 2007-2013.

The project for the purchase and operation of high-resolution spectroscopic cameras is partially funded by the Regional Cooperation Program of the Czech Academy of Sciences, registration number R200402101.