Europlanet Science Congress 2022
Palacio de Congresos de Granada, Spain
18 – 23 September 2022
Europlanet Science Congress 2022
Palacio de Congresos de Granada, Spain
18 September – 23 September 2022
Observing and modelling meteors in planetary atmospheres


Observing and modelling meteors in planetary atmospheres
Co-organized by TP
Conveners: Eleanor Sansom, Maria Gritsevich
| Fri, 23 Sep, 17:30–18:30 (CEST)|Room Albéniz+Machuca
| Attendance Thu, 22 Sep, 18:45–20:15 (CEST) | Display Wed, 21 Sep, 14:00–Fri, 23 Sep, 16:00|Poster area Level 2

Session assets

Discussion on Slack

Orals: Fri, 23 Sep | Room Albéniz+Machuca

Chairpersons: John Plane, Joe Zender
Simon Anghel, Dan-Alin Nedelcu, Mirel Birlan, and Ioana Boaca

Introduction: Recent expansions in fireball networks has lead to an increase in the number of events recorded each night. Due to the mechanism at the source of the detection procedure (i.e. tracking sources of light), the majority of the events is comprised of false meteors. These make their way in trajectory computations, and lead to erroneous orbits [e.g. 1].

Aims: For this study we explore several machine learning (ML) models for their ability to filter the false detections.

Methods: First, a supervised validation was employed on the meteor detections obtained by stations within the Meteorites Orbits Reconstruction by Optical Imaging (MOROI) network [1, 2], between 2017-2020.  Next, a set of ML models suited for classification were applied to a selection of features computed from the data. Finally, each model was tuned to their optimal hyper-parameter value, to obtain the highest score.

Results: The Neural networks method was found to best filter out the false meteors, with a recall score of 96%, followed by 95% for Gradient Boost and Random Forest algorithms. The score is expected to increase when employing a spatio-temporal filter and pixel brightness information. The results entail follow-up studies on the currently expanding FRIPON network [4].

References: [1] Gural et al. (2020) Planetary and Space Science 182, 104847. [2] Nedelcu D. A. et al. (2018) Romanian Astronomical Journal 28, 1, 3-11. [3] Anghel S. et al. (2021) in LPI Contributions 84, Abstract #6027. [3] Colas F. et al. (2020) Astronomy & Astrophysics 644:A53.

How to cite: Anghel, S., Nedelcu, D.-A., Birlan, M., and Boaca, I.: Machine learning methods applied to meteor detection filtering, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-1107,, 2022.

John Plane, Sandy James, Benjamin Murray, Graham Mann, and Margaret Campbell-Brown

Cosmic dust consists of mineral grains that are held together by a refractory organic "glue", and it has been proposed that loss of the organics during atmospheric entry can lead to the fragmentation of dust particles into sub-micron sized fragments (Campbell-Brown 2019). If this happens, there are several important implications in the Earth’s atmosphere: 1) slow-moving particles may be undetectable by radar, so that the total dust input could be considerably larger than current estimate of around 30 tonnes per day that is required to explain the measured vertical fluxes of Na and Fe atoms in the mesosphere, and the accumulation rate of cosmic spherules and unmelted micrometeorites at the surface (Carrillo-Sánchez et al. 2020, Rojas et al. 2021); 2) meteoritic fragments may freeze stratospheric droplets in the polar lower stratosphere, producing polar stratospheric clouds that cause ozone depletion (James et al. 2018); and 3) the anomalously large measured accumulation rates of meteoritic material in polar ice cores may be better explained (Brooke et al. 2017). Meteoritic fragmentation may also supply nuclei for the formation of ice clouds in other planetary atmospheres, such as Mars (Plane et al. 2018).  

At Leeds we have developed a new experimental system for studying the pyrolysis of the refractory organic constituents in cosmic dust during atmospheric entry (Bones et al. 2022). The pyrolysis kinetics of meteoritic fragments was measured by mass spectrometric detection of CO2 at temperatures between 625 and 1300 K. The complex time-resolved kinetic behaviour is consistent with two organic components – one significantly more refractory than the other, probably corresponding to the insoluble and soluble organic fractions, respectively (Alexander et al. 2017). The measured temperature-dependent pyrolysis rates were then incorporated into the Leeds Chemical Ablation Model (CABMOD) (Vondrak et al. 2008), which demonstrates that organic pyrolysis should be detectable using high performance large aperture radars (Bones et al. 2022). Atomic force microscopy was used to show that although the residual meteoritic particles became more brittle after organic pyrolysis, they will nevertheless withstand stresses that are at least 3 orders of magnitude higher than would be encountered during atmospheric entry. This suggests that most small cosmic dust particles (radius < 100 μm) will not fragment during entry into the atmosphere as a result of organic pyrolysis (Bones et al. 2022).

However, a subset of slow-moving, low density particles with a large organic component, as observed in fresh cometary particles such as those in the coma of comet 67/P (Mannel et al. 2019), could fragment into sub-micron meteoritic particles that would survive entry. In fact, meteoritic fragments with a size distribution peaking around radius = 250 nm have been observed in the Arctic polar vortex (Schneider et al. 2021). Experiments in our laboratory show that meteoritic fragments, as well the nanometre-sized meteoric smoke particles which form from the condensation of metallic vapours produced by meteoric ablation in the upper mesosphere, are very effective ice nuclei. On Earth, these particles can facilitate the freezing of polar stratospheric cloud droplets, and may also play a role in the freezing of clouds in the middle atmospheres of Mars and Venus.

Alexander C.M.O., Cody G.D., De Gregorio B.T., Nittler L.R., Stroud R.M., 2017, Chemie Der Erde-Geochemistry, 77, 227

Bones D.L., Sánchez J.D.C., Connell S.D.A., Kulak A.N., Mann G.W., Plane J.M.C., 2022, Earth Space Sci., 9, art. no.: e2021EA001884

Brooke J.S.A., Feng W.H., Carrillo-Sanchez J.D., Mann G.W., James A.D., Bardeen C.G., Plane J.M.C., 2017, J. Geophys. Res.-Atmos., 122, 11112

Campbell-Brown M.D., 2019, Planet. Space Sci., 169, 1

Carrillo-Sánchez J.D., Gómez-Martín J.C., Bones D.L., Nesvorný D., Pokorný P., Benna M., Flynn G.J., Plane J.M.C., 2020, Icarus, 335, art. no.: 113395

James A.D., Brooke J.S.A., Mangan T.P., Whale T.F., Plane J.M.C., Murray B.J., 2018, Atmos. Chem. Phys., 18, 4519

Mannel T., et al., 2019, Astron. Astrophys., 630, art. no.: A26

Plane J.M.C., Carrillo-Sanchez J.D., Mangan T.P., Crismani M.M.J., Schneider N.M., Maattanen A., 2018, J. Geophys. Res.-Planets, 123, 695

Rojas J., et al., 2021, Earth Planet. Sci. Lett., 560, art. no.: 116794

Schneider J., et al., 2021, Atmos. Chem. Phys., 21, 989

Vondrak T., Plane J.M.C., Broadley S., Janches D., 2008, Atmos. Chem. Phys. , 8, 7015

How to cite: Plane, J., James, S., Murray, B., Mann, G., and Campbell-Brown, M.: Ablation Rates of Organic Compounds in Cosmic Dust: Implications for Fragmentation during Atmospheric Entry, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-229,, 2022.

Joe Zender, Detlef Koschny, Regina Rudawska, Salvatore Vicinanza, Stefan Loehle, Martin Eberhardt, Arne Meindl, Hans Smit, Lionel Marraffa, Rico Landman, and Daphne Stams

This talk will introduce the The Canary Island Long-Baseline Observatory (CILBO), a double station meteor camera setup located on the Canary Islands and operated by ESA’s Meteor Research Group since 2010.

Our observations of meteors are obtained in the visual wavelength band by intensified video cameras from both stations, supplemented by an intensified video camera mounted with a spectral grating at one of the locations. The cameras observe during cloudless and precipitation-free nights and data are transferred to a main computer located at ESA/ESTEC once a day. The image frames that contain spectral information are calibrated, corrected, and finally processed into line intensity profiles. An ablation simulation, based on Bayesian statistics using a Markov-Chain Monte-Carlo method, allows to determine a parameter space, including the ablation temperatures, chemical elements and their corresponding line intensities, to fit against the line intensity profiles of the observed meteor spectra. The algorithm is presented in this talk. Several hundred spectra have been processed and will be made available through the Guest Archive Facility of the Planetary Science Archive of ESA.   

How to cite: Zender, J., Koschny, D., Rudawska, R., Vicinanza, S., Loehle, S., Eberhardt, M., Meindl, A., Smit, H., Marraffa, L., Landman, R., and Stams, D.: Spectral Observations at the CILBO Observatory: Calibration andData Sets, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-99,, 2022.

Joachim Balis, Hervé Lamy, Michel Anciaux, and Emmanuel Jehin

When meteoroids hit Earth’s atmosphere molecules, they leave a trail of plasma behind. This region, composed of free electrons and positively charged ions, is capable of reflecting radio signals. The analysis of such signals along the meteoroid path can be used for various scientific purposes: quantification of the electron line density, analysis of the thermosphere properties, characterization of the meteor ablation process, etc. To achieve these objectives, the meteoroid trajectory needs first to be determined.  

The reflection on the plasma trails is usually assumed to be specular, which means that the radio wave is reflected only at a given point along the meteoroid trajectory. For forward scatter systems, the position of this specular point depends on the trajectory on the one hand, and on the position of both the emitter and the receiver on the other hand. Using non-collocated receivers, one obtains several specular points along the trajectory. The receivers will thus detect the reflected signal at different time instants on a given trajectory. 

In this work, we propose a method that aims at reconstructing meteoroid trajectories using only the time differences of the meteor echoes measured at the receivers of a forward scatter radio system, such as the BRAMS (Belgian RAdio Meteor Stations) network. The latter uses the forward scatter of radio waves on ionized meteor trails to study meteoroids falling in the Earth’s atmosphere. It is made of a dedicated transmitter and 42 receiving stations located in and nearby Belgium. Given that all the BRAMS receivers are synchronized using GPS clocks, we can compute the time differences of the meteor echoes and use them to find the meteoroid trajectory. 

Assuming a constant speed motion, the position (three degrees of freedom) and the three velocity components have to be determined. This inverse problem is non-linear and requires the definition of a target objective to minimize. Two different formulations are compared: the first one is based on the minimization of the bistatic range while the second one uses a forward model, which defines the trajectory as being tangential to a family of ellipsoids whose loci are the emitter and each receiver. A Monte-Carlo analysis is performed to highlight the sensitivity of the output trajectory parameters to the input time differences. 

The BRAMS network also includes an interferometer in Humain (south of Belgium). Unlike the other receiving stations, it uses 5 antennas in the so-called Jones configuration (Jones et al., 1998; Lamy et al., 2018) and allows to determine the direction of arrival of the meteor echo to within approximately 1°. In that case, the problem becomes much easier to solve because the interferometer gives information about the direction of a reflection point. The benefits brought by such a system regarding the accuracy of the trajectory reconstruction are highlighted. 

The post-processing steps allowing to extract meteor echoes from the raw radio signals are described. An approach to properly filter out the direct beacon signal is introduced. Indeed, each receiver detects a more or less strong direct signal coming from the transmitter. This signal does not contain any information about the meteor path since it simply propagates through the atmosphere and is not reflected on the meteor trail. Knowing that the BRAMS transmitter emits a continuous cosine wave, the amplitude, the frequency and the phase are fitted in the frequency domain. The beacon signal is finally reconstructed in the time domain and subtracted. This process in illustrated in the following figure, which shows an example of spectrograms (i.e. time-frequency maps where the power is color-coded) before and after the beacon signal subtraction. The proper removal of the horizontal line at around 1005 Hz (corresponding to the direct signal) is apparent in the bottom spectrogram. 


Afterwards, a bandpass filter is necessary to fully exploit the echoes of the detected meteors. Indeed, the raw signal at the time of the meteor echo is noisy and can have interfering signals caused by the reflections on aircrafts. If the latter are at slightly different frequencies than the meteor echo, they produce interference beats. A windowed-sinc filter Blackman filter of high order is therefore used to remove the signal components at frequencies where the meteor echo does not appear. The time corresponding to half-peak power in the rising edge of the echo (which marks the passage of the meteoroid at the specular reflection point) is finally retrieved and the time differences are computed.  

To analyze the accuracy of the trajectory reconstructions, data from the optical CAMS-BeNeLux network are used. Promising results showing the reconstructed position, velocity and inclination of several meteoroid trajectories with and without the interferometer are discussed. In the following figure, an example of CAMS trajectory reconstruction obtained with our post-processing is shown. The blue line corresponds to the trajectory determined with the CAMS network, while the purple line is obtained through our analysis of the radio signals obtained at the BRAMS receivers. The reconstructed trajectory using the time differences only (method 1) is shown on the left. The trajectory obtained thanks to the combination of time differences and interferometric data (method 2) is given on the right. 


How to cite: Balis, J., Lamy, H., Anciaux, M., and Jehin, E.: Reconstructing meteoroid trajectories using forward scatter radio observations and the interferometer from the BRAMS network, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-227,, 2022.

Apostolos Christou and Nikolaos Georgakarakos

Recent meteor radar surveys have uncovered a subpopulation of meteoroids with high orbital inclination and at a=1 au, in the form of a grouping of radiants within the southern toroidal source of sporadic meteors (Brown et al, Icarus, 2010;  Pokorny et al, Icarus, 2014). Many of these showers are so far not detected in optical surveys (Jenniskens et al, PSS, 2018; Bruzzone et al, PSS, 2020), implying a meteoroid population deficient in large particles, such as might result from the gradual, size-sorting action of P-R drag.

Here we consider that the source of this population is one or more Near-Earth Asteroids (NEAs) in similar, high inclination orbits. We test this hypothesis by numerical integration of test particles ejected from a selection of suitable NEAs and evolving under the influence of radiation forces. We pay particular attention to the role of dynamical resonances near Earth's orbit as well as the Kozai mechanism in confining the meteoroids, countering the dispersive action of drag forces and gravitational scattering.

We will report on the outcome of our simulation runs at the meeting.

How to cite: Christou, A. and Georgakarakos, N.: High-inclination NEAs as meteor stream parent bodies, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-708,, 2022.

Juan Diego Carrillo Sanchez, Diego Janches, John M. C. Plane, Petr Pokorny, Menelaos Sarantos, Matteo M. J. Crismani, Wuhu Feng, and Dan R. Marsh

This study provides a comprehensive description of the deposition of meteor-ablated metals in the upper atmosphere of Mars, accounting for the temporal, vertical, latitudinal, and seasonal distribution. For this purpose, the Leeds Chemical Ablation MODel (CABMOD) is combined with a Meteoroid Input Function (MIF) to characterize the size and velocity distributions of three distinctive meteoroid populations around Mars – the Jupiter-Family Comets (JFCs), main-belt asteroid (ASTs), and Halley-Type Comets (HTCs). These modelling results show a significant midnight-to-noon enhancement of the total mass influx because of the orbital dynamics of Mars, with meteoroid impacts preferentially distributed around the equator for particle with diameters below 2000 µm. The maximum total mass input occurs between the northern winter and the first crossing of the ecliptic plane with 2.30 tons sol-1, with the JFCs being the main contributor to the overall influx with up to 56% around the Mars equator. Similarly, total ablated atoms mainly arise from the HTCs with a maximum injection rate of 0.71 tons sol-1 spanning from the perihelion to the northern winter. In contrast, the minimum mass and ablated inputs occur between the maximum vertical distance above the ecliptic plane and the aphelion with 1.50 and 0.42 tons sol-1, respectively. Meteoric ablation occurs approximately in the range altitude between 100 and 60 km with a strong midnight-to-noon enhancement at equatorial latitudes. The eccentricity and the inclination of Mars’ orbit produces a significant shift of the ablation peak altitude at high latitudes as Mars moves towards, or away, from the northern/southern solstices.

How to cite: Carrillo Sanchez, J. D., Janches, D., Plane, J. M. C., Pokorny, P., Sarantos, M., Crismani, M. M. J., Feng, W., and Marsh, D. R.: A modelling study of the seasonal, latitudinal, and temporal distribution of the meteoroid mass input at Mars:  Constraining the deposition of meteoric ablated metals in the upper atmosphere, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-21,, 2022.

Display time: Wed, 21 Sep 14:00–Fri, 23 Sep 16:00

Posters: Thu, 22 Sep, 18:45–20:15 | Poster area Level 2

Chairpersons: Hervé Lamy, Ioana Lucia Boaca
Dolores Maravilla, Marni Pazos, and Guadalupe Cordero


In this paper we present the results obtained from the spectral analysis using the wavelet technique of a time series of brightest fireballs to look for periodicities associated with other bodies of our Solar System. The spectra show four periodicities at 106.2 days, 12.7 days, 2.5 days, 10.3 years and 4.6 years. In particular the periodicities around 12.7 and 2.5 days could be related to the Carrington rotation period.



One of the main problems of Planetary Sciences is to understand the dynamical behavior of asteroids, meteors and meteoroids inhabiting near our planet, mainly those that fall on terrestrial surface. These bodies feel the planetary and solar gravitational influence when they travel across the interplanetary medium or mainly when they are in the terrestrial neighborhood of one of those bodies. The detection of meteoroids falling on Earth using several instruments has been important because it has permitted to obtain very useful data. The analysis of these data can help to identify the physical interactions that occur between these bodies and the rest of the bodies in the solar system. Additionally in recent decades, multiple modeling and numerical simulation works have been carried out to fully understand the origin of such interactions.


The spectral method

A time series of brightest fireballs from January, 1998 to December, 2020 was spectrally studied using the wavelet technique to look for periodicities related with Solar System bodies relationships. The data were taken from the Near Earth Object Program ( Because of this time series has gaps, the wavelet transform was used to do the spectral analysis. The method was applied using the Morlet function (eq. 1) [1] to analyze the power spectral density (PSD) of brightest fireball meteors [1], [2], [3].


Where ω0 and η are both non-dimensional frequency and time parameter respectively


Results and discussion

Five periodicities were identified from the wavelet spectral analysis (figure 1). They are located at 2.5 days, 12.7 days, 106.2 days, 4.6 years and 10.3 years. The figure 1 shows the power spectral density spectra (PSD) where these periodicities can be seen on the right side of the plot. They are inside the cone of influence (COI) and were obtained with a confidence level of 85%. The uncertainties of every peak position were obtained from the peak full width at half maximum.



Figure 1: PSD of a time series of brightest fireballs from January, 1998 to December, 2020. On the right side of the plot, five peaks at 2.5, 12.7 and 106.2 days and at 4.6 and 10.3 years are shown.

In particular the periodicity around 12.7 days could be the first harmonic of the Carrington rotation period (27 days), [4] indicating that the solar gravitational force could be modulating the meteoroids entrance on the Terrestrial atmosphere. Carrington rotation has been detected in several time series as is the case of solar spots, storm sudden commencements, cosmic rays, among others. The periodicity around 2.5 days, it could be a small harmonic of the solar rotation period.

The mechanism behind the relationship between the variable solar radiation (due to its rotation and the solar cycle) and the fall of small asteroids to Earth´s atmosphere could be associated to the Yarkovsky and /or YORP effects. Several works have shown that the solar radiation is able to modify asteroidal orbits and rotational periods [5, 6], and it is possible that the periodicity in the variability of this radiation be the cause of periodicities in the falling of asteroidal material observed in this work. Respect to the periodicities around 4.6 and 10.3 years, they could be related to the magnetic solar cycle. The 4.6 years periodicity could be related to Jupiter too. According to NASA ( w/), the Jupiter orbital period is 4333 Earth days, so the ratio between this period and 1679 Earth days (̴ 4.6 year period) is almost 13/5.


Summary and Conclusions

1. The Sun could be a gravitational trigger of meteoroids from their neighborhood to Earth.

2. The periodicity around 12.7 days is possible associated with the Carrington rotation as well as the 2.5 days periodicity.



[1] Torrence, Ch., Compo, G. P.: A practical guide to wavelet analysis, Bulletin of American Meteorogical Society, vol. 79, No. 1, pp. 61-78, 1998.<0061:APGTWA>2.0.CO;2

[2] Soon, W., Dutta, K., Legates, D. R., Velasco, V., Zhang, W.: Variation in surface air temperature of China during the 20th century, J. Atmos. Sol-Terr. Phy. 73, pp. 2331-2344, 2011.

[3] Velasco Herrera, V. M., Soon, W., Velasco Herrera, G., Traversi, R., Horiuchi, K.: Generalization of the cross-wavelet function, New Astronomy, 56, pp. 86-93, 2017.

[4] Nayar, S. R. P.: Periodicites in solar activity and their signature in the terrestrial environment, ILWS Workshop 2006, Goa, India, February 19-24, pp. 1-9, 2006.

[5] Farnocchia, D., Chesley, S. R., Takahashi, Y., Rozitis, B., Vokrouhlický, D., Rush, B. P., Mastrodemos, N., Kennedy, B.M., Park, R. S., Bellerose, J., Lubey, D. P., Velez, D., Davis, A.B., Emery, J. P., Leonard, J. M., Geeraert, J., Antreasian, P.G., Lauretta, S.: Ephemeris and Hazard Assessment for Near-Earth Asteroid (101955) Bennu Based on OSIRIS-REx Data, Icarus, 369,, 2021.

[6] Zegmott, T. J., Lowry, S. C., Rozek, A., Rozitis, B., Nolan, M. C., Howell, E.S., Green, S. F., Snodgrass, C., Fitzsimmons, A., Weissman, P. R.: Detection of the YORP Effect on the Contact Binary (68346) 2001 KZ66 from Combined Radar and Optical Observations, Monthly Notices of the Royal Astronomical Society. 507, pp. 4914-4932,, 2021.

How to cite: Maravilla, D., Pazos, M., and Cordero, G.: Are fireballs fall on Earth modulated by our star?, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-26,, 2022.

Ioana Lucia Boaca, Jarmo Moilanen, Maria Gritsevich, Mirel Birlan, Alin Nedelcu, Tudor Boaca, François Colas, Adrien Malgoyre, Brigitte Zanda, and Pierre Vernazza

1. Introduction
The Fireball Recovery and Inter Planetary Observation Network (FRIPON) network [1] uses all-sky cameras in order to detect fireballs. The FRIPON network comprises over 150 cameras installed all over Europe [1]. In this work we focus on the results obtained by the Meteorite Orbits Reconstruction by Optical Imaging (MOROI) [2] component of the FRIPON network in Romania. As of May 2022, the MOROI network detects the events with the use of 13 all-sky cameras.
2. Methods
The method for computing the fireball trajectory used by FRIPON is presented in [3].
The height, velocity and slope γ of the meteoroid are the input data for computing the ballistic coefficient α and the mass-loss parameter β. We select the candidates that are likely to produce meteorites of the ground using the α-β algorithm presented in [4], [5], [6], [7].

3. Results

Starting from January 2021 (the starting moment of data fusion of the MOROI network into the FRIPON network) until the present time (May 2022) over 100 meteors were detected. We present the most spectacular events that are likely to result on a meteorite production on the surface of the Earth. 

Figure 1: The outcome of the FRIPON (MOROI) detections in Romania

In Figure 1 are represented the coordinates of the meteoroids with noticeable deceleration in the (ln(αsinγ),lnβ) coordinates system. The values of the shape parameter correspond to the cases when the meteoroid doesn’t rotate (µ=0) or rotates uniformly (µ=2/3). 

The boundaries (‘likely fall’, ‘possible fall’, ‘unlikely fall’) are represented for meteoroids with final mass of 50 g.

We processed the 100 detections of the FRIPON (MOROI) network in Romania. From this amount of data, we found 15 fireball events with noticeable deceleration. We found one event in the ‘likely fall’ area and three events in the ‘possible fall’ area. The fireball that is likely to produce meteorites was detected by the MOROI network on 24.11.2021 at 19:20:57 UT.

We model the dark flight trajectory of the meteoroids with the ‘likely fall’ and ‘possible fall’ outcomes and determine their strewn field with the model presented in [8], [9]. We use the wind model from the European Centre for Medium-Range Weather Forecasts (ECMWF).

A meteorite recovery campaign will be organised to identify the strewn field area.


The work of IB and MB was partially supported by a grant of the Romanian Ministry of Education and Research, CNCS-UEFISCDI, project number PN-III-P1-1.1-PD-2019-0784, within PNCDI III. The work of IB, MB, AN was partially supported by a grant of the Ministry of National Education and Scientific Research, PNIII-P2-1214/25.10.2021, program no. 36SOL/2021. JM and MG acknowledge the Academy of Finland project no. 325806 (PlanetS).


[1] Colas F., Zanda B., Bouley S., Jeanne S., Malgoyre A., Birlan M., Blanpain C., Gattacceca J., Jorda L., Lecubin J., et al. (385 more) FRIPON: a worldwide network to track incoming meteoroids. Astronomy &. Astrophys. 644, A53. doi:10.1051/0004-6361/202038649. 2020.

[2] Nedelcu D.A., Birlan M., Turcu V., Boaca I., Badescu O., Gornea A., Sonka A.B., Blagoi O., Danescu C., Paraschiv P. Meteorites Orbits Reconstruction by Optical Imaging (MOROI) Network. Romanian Astronomical Journal 28(1), 57 – 65. 2018.

[3] Jeanne, S., Colas, F., Zanda, B., Birlan, M., Vaubaillon, J., Bouley, S., Vernazza, P., Jorda, L., Gattacceca, J., Rault, J. L., Carbognani, A., Gardiol, D., Lamy, H., Baratoux, D., Blanpain, C., Malgoyre, A., Lecubin, J., Marmo, C., Hewins, P. Calibration of fish-eye lens and error estimation on fireball trajectories: application to the FRIPON network. Astronomy and Astrophysics, 627:A78. 2019.

[4] Gritsevich, M. I. The Pribram, Lost City, Innisfree, and Neuschwanstein falls: An analysis of the atmospheric trajectories. Solar System Research.42, 372–390. 2008.

[5] Gritsevich, M.I., Stulov, V.P., Turchak, L.I. Consequences of collisions of natural cosmic bodies with the Earth's atmosphere and surface. Cosmic Research vol.50, no.1, 56-64. 2012.

[6] Sansom, E.K., Gritsevich, M., Devillepoix, H.A.R., Jansen-Sturgeon, T., Shober, P.,

Bland, P.A., Towner, M.C., Cupák, M., Howie, R.M., Hartig, B.A.D. Determining Fireball Fates Using the α-β Criterion. Astrophysical Journal 885(2):115. 2019.

[7] Boaca I., Gritsevich M., Birlan M., Nedelcu, A., Boaca, T., Colas, F., Malgoyre, A.,

Zanda, B., Vernazza P., to be submitted. 2022.

[8] Moilanen, J., Gritsevich, M., Lyytinen, E., Determination of strewn fields for meteorite falls, Monthly Notices of the Royal Astronomical Society 503, 3337–3350. 2021.

[9] Boaca I., Nedelcu A., Birlan M., Boaca T., Anghel S. Mathematical model for the dark-flight trajectory of a meteoroid, Romanian Astronomical Journal, Vol. 31, No. 2. 2021.


How to cite: Boaca, I. L., Moilanen, J., Gritsevich, M., Birlan, M., Nedelcu, A., Boaca, T., Colas, F., Malgoyre, A., Zanda, B., and Vernazza, P.: Analysis of the meteorite-producing fireballs registered by the MOROI component of the FRIPON network, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-160,, 2022.

Mátyás Bejó, Tibor Hegedűs, Benke Hargitai, Barnabás Molnár, Áron Sztojka, and Ágota Lang



Meteorites offer large quantities of interesting and useful information regarding the formation of the Earth, the Solar System and maybe the life, but for their study, they have to be found first. This is not an easy task since these objects only glow in the upper layers of the atmosphere and after that, there is no information about their locations. Our project aims to model this phase of meteor flight, the so-called ‘dark flight’, and gather as much information about it as possible, regarding the meteors’ location, velocity, etc. 


In Hungary Dr Tibor Hegedüs and his high-altitude balloon team (called DAMBALL) released the task to simulate the dark flight of meteoroids by ‘artificial meteoroid’ bodies, which have their own telemetry. A part of our group (‘Soprobotics’) has developing and programming such compact data-collecting devices that can be inserted in small spheres, the falling trajectories of which would be analogous to a meteor in the phase of dark flight. These units were named Info-Droplets. When creating the droplets, the main concept was keeping them as small as possible. The desirable size were defined within the range of D=5-10 cm




The Droplets’ main components

Control of one device is fulfilled by a WEMOS D1 mini pro microcontroller. The most important tool of the position measurement is a GPS module, this supplies the data required by the observing team. The collected data are stored on a SD card which has its own shield. The unit is powered by a 3.7V LiPo battery.


Evolution of the Droplets’ design


Mk 1:

This first device was consisted only one microcontroller, an SD-Card shield and an OCTOPART GPS which was provisionally connected with wires. This GPS works up to an altitude of 18 km due to a built-in limitation and thus it was insufficient for our purposes.


Mk 2:

The GPS was replaced by a UBLOX-NEO-M8Q which does not have the previously mentioned height limitation. This was planted on a custom PCB.

For the additional functionality of Droplet-Droplet and Droplet-Ground communication, a LoRa RFM 95W radio module was added. This offers help in finding the droplets after the flight and supplies a log of measured data in case a unit should be lost or destroyed.


Mk 3:

Further test flights revealed potential improvements which were duly implemented. 

A new, active GPS antenna was added, the GPS shield was redesigned placing the LoRa on it as well and adding a port for the GPS antenna and a battery-control shield was added for constant supply-voltage and charging capabilities. 



We programmed the microcontrollers in the Arduino IDE. For the GPS we used the TinyGPS++ library and the radio modules had their own library. This did not support the ESP based boards, but we could modify it, so the two devices could work together.

The data collected during the fall are easily importable to Excel.


Code structure:

Upon turning on the droplet we are running the setup. Here we are starting every module (SD card, Radio, Gps). 

In the main loop we are reading the GPS and storing the data on the card. Then the communication starts via radio with the other droplets, and with the Earth unit as well.



In the setup procedure, several fundamental things are started.

Some basic information, we have :
GPS communication pins, droplet ID, droplet version, software version, etc.

Finally, we are starting the radio and the GPS. Both modules are using SPI, we can select the one we are using through its chip selector pin.


Main loop:

Firstly, we are measuring the position of the unit by the GPS and saving it in the data variable. This includes the droplet ID, the number of satellites,  time, latitude, longitude and the altitude.

For safety purposes we write the same data into two files simultaneously.


The first part of the communication is the sending of the data variable to the other droplet and to the Earth unit. The second part is the receiving and saving the data acquired from the other droplets.


Additional features:

If the GPS loses its signal, the droplet detects this and restarts.

We can also send some commands to the droplet via radio from the Earth unit. 

We can restart the whole device, the GPS, the radio, and get the file version and wipe the whole SD card remotely.

Test flights and results

The high-altitude balloons can carry the Droplets to a height of about or more then 30 km where they blow up. The gondola, and the previously separated Droplets fall to the ground (the gondola is with a parachute and the Droplets are by a free-fall) 


August 2018: Droplets Mk 1

From the data logs it was apparent that both the climb and the fall was well documented, but the part of the flight above 18000m altitude is missing owing to the GPS’s built in limitation.


September 2019: Droplets Mk 2

The first flight, where we used radio communication, but the flight data was corrupted and could not be evaluated.


June 2020: Droplets Mk 2

The horizontal part of the graph is not caused by the altitude cutoff as the UBLOX GPS was used, but the GPS modules crashed and the satellite communication was severed. Although radio communication between Droplets and the Ground unit was active, we could not solve the problem at that time.


Sadly no further test flights could be conducted to date because of the COVID 19 pandemic, thus the Droplets could not be built into their spherical housings and dropped separately from the gondola to be perfect meteor-models.

Summary and conclusions

Three successful test flights were conducted and the graphs show that our Droplets – which became quite more complex in the meantime, than our concept at the start of the project – work satisfactorily and the balloon team can use them for the original task at hand. The final test flight and the actual missions are planned for this summer.

How to cite: Bejó, M., Hegedűs, T., Hargitai, B., Molnár, B., Sztojka, Á., and Lang, Á.: Modelling the fall of meteors during the dark flight with Info-Droplets, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-900,, 2022.

Petr Kubelík, Jakub Koukal, Libor Lenža, Jiří Srba, Vojtěch Laitl, Radka Křížová, Anna Křivková, Svatopluk Civiš, Vladislav Chernov, and Martin Ferus

The visible spectrum of a bright Leonid bolide was recorded and analyzed by fitting the parameters of a newly developed numerical plasma model. In this procedure, elemental composition, electron density, plasma temperature, and the density of the heavy particles were extracted from the observed spectrum. The model introduced in this study involves self-absorption and takes into account the effects of the non-homogeneous meteoric plasma on the observed emission spectra using a simple radiative transfer model.

The research was funded by the Czech Science Foundation (projects nos. 18-27653S, 21-11366S and 20-10591J) and partially Russian Foundation for Basic Research (grant no. 19-52-26006). Department of Spectroscopy is supported by the ERDF/ESF "Centre of Advanced Applied Sciences" project no. CZ.02.1.01/0.0/0.0/16_019/0000778.

How to cite: Kubelík, P., Koukal, J., Lenža, L., Srba, J., Laitl, V., Křížová, R., Křivková, A., Civiš, S., Chernov, V., and Ferus, M.: Plasma physics and elemental composition of a Leonid meteor: Application of a complex plasma radiation model., Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-908,, 2022.

Pavel Koten and David Čapek

Several meteor clusters were observed by the video cameras deployed within the Czech Republic in recent years. Moreover, we also obtained data on another cluster which was detected above the Southern America.

In this talk the basic data on the selected meteor clusters, their atmospheric trajectories, and 3D distribution of the fragments will be provided. For example, a cluster consisting from a fireball and four fainter meteors was observed on August 23, 2020. It was a relatively compact cluster with smaller meteoroids up to 30 kilometres from the main body. Possible origin of the clusters will be discussed, too.

How to cite: Koten, P. and Čapek, D.: Meteor clusters observed by the video technique, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-420,, 2022.

Hervé Lamy, Cis Verbeeck, Joachim Balis, Michel Anciaux, Stijn Calders, Antoine Calegaro, and Antonio Martinez Picar

BRAMS (Belgian RAdio Meteor Stations) is a network using forward scatter of radio waves on ionized meteor trails to study meteoroids. It is made of a dedicated transmitter and of 42 receiving stations located in or near Belgium. The network started in 2010 but has recently been extended and upgraded.

The transmitter emits a circularly polarized CW radio wave with no modulation at a frequency of 49.97 MHz and with a power of 130 W. Each receiving station uses a 3-element zenith pointing Yagi antenna. The first stations used analog ICOM-R75 receivers and a PC. Since 2018, new improved stations have been installed using digital RSP2 receivers, a GPSDO and a Raspberry Pi, providing better dynamic, sensitivity and stability.

A vast majority of the meteor echoes detected by BRAMS are specular, which means that most of the power of the meteor echoes comes from a small region along the meteoroid path centered on the specular reflection point, a point which is tangential to a prolate ellipsoid having the transmitter and the receiver as the two foci. This puts important geometrical constraints on whether a specific meteoroid trajectory can be detected or not by a given receiving station since the position of the reflection point must fall within the so-called meteor zone.

As a consequence, for meteor showers, the observed activity based on the raw counts of meteor echoes recorded by a BRAMS station is modulated by the position of the radiant throughout the day and does not truly reflect the real activity of the shower.  A possibility to correct these raw counts is to compute the so-called Observability Function (OF) introduced by Hines (1958) and further developed by Verbeeck (1997). This OF contains a geometrical part which provides the location of potentially observable meteor trails at a given moment and for a given station, and another part which takes into account which fraction of these trails will actually be detected by the receiving station.  Indeed, whether a meteor echo will be detected at the station also depends on the sensitivity of the receiving chain, on the power transmitted and on the ionization at the reflection point, the latter depending on the initial mass of the meteoroid.

We will describe how the geometrical part of the OF is calculated and will provide results for several receiving stations of the BRAMS network to emphasize the importance of the geometry. We will also describe how we take into account important characteristics of the system to determine the sensitivity of the receiving chain such as the gains of the antenna in the direction of the meteor echoes.  Finally, we will apply the OF to the raw counts of a few main meteor showers (e.g. Perseids, Geminids, Quadrantids) obtained from the Citizen Science project, the Radio Meteor Zoo, that we have developed since 2016 in cooperation with Zooniverse (


Hines, C., Can. J. Phys., 36, 117-126, 1958

Verbeeck, C., Proceedings of the International Meteor Conference, Apeldoorn, the Netherlands, 122-132, 1996

How to cite: Lamy, H., Verbeeck, C., Balis, J., Anciaux, M., Calders, S., Calegaro, A., and Martinez Picar, A.: Observability Function of the BRAMS forward scatter network, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-261,, 2022.

Brayden Noh

Asteroid parameters such as size, density, and velocity govern how the asteroid is deformed in the atmosphere, forecasting if the asteroid will explode in the air (airburst) or impact the ground. A broad outline for asteroids entering the atmosphere is simple. Large asteroids survive, while small asteroids disintegrate by air friction. However, the simple concept of kinetic energy lost by air can be extended by adding a relevant aspect of asteroids: porosity. In small solar system objects, asteroids are expected to have porosities of 10-60%, and pore spaces change how the asteroid is compact with pressure, leading to more complex asteroid interaction with the atmosphere. Asteroids fall at thousands of meters per second, conventionally making it difficult to observe. Therefore, computational simulations will allow us to visualize how porosity influences the asteroid during its atmospheric entry.
Visualizing the simulation data is critical to properly understanding the asteroid atmospheric entry and impact crater process. The fundamental belief of the project is not only to make comprehensive visualizations but ones that the audience can understand without any background knowledge. Using iSALE2D, internal physical model of the asteroid are presented. The visualization shows that asteroid porosity level has fundamental effects on atmospheric entry and impact cratering process. Therefore, when looking into hazardous asteroids, not only we should consider size, density, and velocity, but also porosity.

How to cite: Noh, B.: Visualizing how asteroids deform during atmospheric entry​, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-73,, 2022.