PS5.1

How to cite: Fedorov, A., Livi, S., Louarn, P., Owen, C., and Raines, J.: Solar Orbiter SWA-PAS and SWA-HIS observations of O+ ions in the very distant tails of the comets C/2019 Y4(ATLAS) and C/2021 A1(Leonard), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12123, https://doi.org/10.5194/egusphere-egu22-12123, 2022.

During cruise from Earth to Jupiter, an attitude-sensing star camera scanned the sky in search of objects large and small. That star camera is part of the Advanced Stellar Compass (ASC), a subsystem of the Magnetometer Investigation charged with providing accurate attitude information at the end of Juno’s magnetometer boom.  The main objective of the cruise observation was to search for smaller, unregistered, solar system objects, but quite unexpectedly the system recorded a great many tiny objects ejected from the spacecraft by the impact of high velocity interplanetary dust particles (IDP). This led to the first ever comprehensive profiling of IDPs from 0.88 to 5.2 AU near the ecliptic plane. We observed a rich IDP population between 1.2AU and the 4:1 mean motion resonance with Jupiter near 2.1AU, and in the Kirkwood gaps, the IDP population drops to near zero beyond the 2:1 mean motion resonance with Jupiter at 3.3AU. However, a hundredfold increase in dust impacts with the spacecraft occurred during a 15-day period in December 2015, shortly before entering the Jovian system. We have identified this event with Juno’s passage through a Jupiter family comet tail. Detailed analysis demonstrates that the comet dust population we observed is characterized by cometary dust particles (CDPs) with a beta in the range of 2-10%. Subdued comet activity far from the Sun frustrates direct observations of the comet tail from Earth; however, our analysis shows that the tail evolution is still dominated by non-gravitational forces acting on particles of a few to tens of micrometers. We present the in-situ comet tail observations and couple these to the complex evolution of comet activity and dust tail dynamics.

How to cite: Jørgensen, J., Jørgensen, P., Benn, M., Andersen, A., Connerney, J., Toldbo, C., Bolton, S., and Levine, S.: The Juno Spacecraft Catches a Jupiter Family Comet by the Tail, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9660, https://doi.org/10.5194/egusphere-egu22-9660, 2022.

Comet C/2016 R2 PanSTARRS presents an unusually high N₂/CO abundance ratio, as well as a heavy depletion in H₂O, making it the only known comet to have this composition. Two studies have independently estimated the possible origin of this comet from building blocks formed in a peculiar region in the protoplanetary disk, near the ice line of CO and N₂. Here we explore the potential fates of comets formed from these building blocks using a numerical simulation of early solar system formation and tracking the dynamics of these objects in the Jumping Neptune scenario. We find that objects formed in the region of the CO- and N₂- icelines a are highly likely to be sent towards the Oort Cloud or ejected from the Solar System altogether on a relatively short timescale, thus offering a potential explanation for the scarcity of comets with R2’s unique composition.  

How to cite: Anderson, S. E., Petit, J.-M., Noyelles, B., Mousis, O., and Rousselot, P.: Peculiar Comets Ejected Early In Solar System Formation, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7975, https://doi.org/10.5194/egusphere-egu22-7975, 2022.

During the ESA/Rosetta mission more than 1.5 million individual mass spectra have been obtained in the coma of 67P/Churyumov-Gerasimenko with the ROSINA/DFMS mass spectrometer. A single spectrum at a specific mass represents the accumulation of 3000 scans with an integration time of 6.6 ms, for a 19.8 s total measuring time.

DFMS data has been a source of information on coma composition and even on refractories. Although DFMS has a high sensitivity and high dynamic range, there may still be species hidden in the spectra. One approach to improve the signal-to-noise ratio is the summation of spectra. This way, species with a low abundance, close to the limit of detection of DFMS, should become more pronounced, however, at the cost of the loss of possible time variability information.  Unfortunately, the creation of sum spectra is not straightforward. Sum spectra need a clean dataset, where all erroneous and non-cometary data have been removed. Also, instrumental effects (e.g. detector aging, changes in settings in the course of the mission) need to be taken into account.

This contribution will present the methodology and some first results for sum spectra from DFMS. It is shown how this approach can provide inputs in the search for Fe and Ni in comet 67P.

How to cite: Dhooghe, F., De Keyser, J., Hänni, N., Altwegg, K., Cessateur, G., Jehin, E., Maggiolo, R., Rubin, M., and Wurz, P.: The search for low-abundant species in the coma of comet 67P/Churyumov-Gerasimenko, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-4474, https://doi.org/10.5194/egusphere-egu22-4474, 2022.

Introduction:

The slow ejecta (i.e., with velocity lower than escape velocity) and landslides are similar. Both are forms of gravity movement. After landing, ejecta may be still moving like a ‘regular’ landslide. On the other hand, the motion of landslides may include free fall without contact with the ground

            Observations of comets 9P/Tempe 1 and 67P/Churyumov – Gerasimenko revealed existence of various forms of mass motion [1, 2, 3]. We compare here landslides of matter from Imhotep (in the lobe Body) and from Hathemit (in the lobe Head) depressions.

                                                        Model of ejection

A simple model of processes leading to the formation of slow ejecta is assumed [3]. The phase transition heats a certain underground volume [4, 5, 6]. It leads to vaporization of volatiles. Eventually a cavity is formed. If the pressure in the cavity exceeds some critical value then the crust could be crushed and its fragments will be ejected in the space. Note that the initial velocity of ejecta are usually approximately perpendicular to the physical surface. This assumption was used successfully in [6].

                                                                  Results

           We found that ejecta with the velocity 0.3 m s^-1 (or lower) land close to the starting point for both considered depressions. Ejecta faster than 0.5 m s^-1 have complex trajectories and may land far from the starting point. For the velocity  0.7 m s^-1 (and higher) some of ejecta did not land during modeling even for Imhotep.

             In [6] we have found that ejecta from Hathemit fall in a wide belt mainly on the one hemisphere. For ejecta from Imhotep there is no such pattern.

             The fate of the ejecta after landing depends on many factors: the friction coefficient, the inclination of the place of landing, the vector of velocity, etc. However, often the motion is determined by small scale details. Note that the sliding grain must overcome the worst obstacle on the landing surface.

                                                 Conclusions and future plans

Determining places of deposition of the material ejected from Imhoteb or Hatmelib will allow to determine the composition of the comet's interior under these regions without the need for drilling. This would be particularly important for future missions to the comet.           

Acknowledgements:

The research is partly supported by Polish National Science Centre (decision 2018/31/B/ST10/00169)

References

[1] Czechowski L., (2017)      Geophysical Research Abstract. EGU 2017 April, 26, 2017

[2] Jorda, L., et al. (2016) Icarus, 277, 257-278, ISSN 0019-1035, https://doi.org/10.1016/j.icarus. 2016.05.002.

[3] Auger, et al., (2015). Astronomy and Astrophysics. 583. A35. 10.1051/0004-6361/201525947.

[4] Kossacki K., Czechowski L., (2018). Icarus vol. 305, pp. 1-14, doi: 10.1016/j.icarus.2017.12.027

[5] Kossacki, K.J., Szutowicz, S., (2010). Icarus 207, 320- 340.

[6] Czechowski L. and Kossacki K.J. (2019) Planetary and Space Science 209, 105358, https://doi.org/10.1016/j.pss.2021. 105358 

How to cite: Czechowski, L. and Kossacki, K.: Ballistic landslides on comet 67P/Churyumov–Gerasimenko, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9496, https://doi.org/10.5194/egusphere-egu22-9496, 2022.

Dust in the interstellar space is illuminated by cosmic radiation that consists of photons of different wavelengths and energetic charged particles. Whereas the photoemission is rather well understood, charging of dust grains due to interaction of with energetic charged particles was not experimentally studied in detail so far. We report the first laboratory experiment dealing with the interaction of a cosmic dust simulant with energetic charged particles emitted from a radioisotope. Measurements of the charge of micrometer silicate dust grains with an accuracy of one elementary charge revealed several processes leading to the dust charging. The observed average rate of charging events agrees well with prediction of a model based on the continuous slowing down approximation of energetic particles inside the grain. Charge steps larger than one elementary charge were attributed to emission of secondary electrons excited by the primary particle slowing down. The determined yield of secondary electron emission is approximately inversely proportional to the grain radius. The experimental results led us to the formulation of a possible scenario of interstellar dark clouds charging.

How to cite: Pavlu, J., Wild, J., Cizek, J., Nouzak, L., Vaverka, J., Safrankova, J., and Nemecek, Z.: Laboratory Simulation of the Dust Interaction with Energetic Particles and its Implication for Interstellar medium, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1363, https://doi.org/10.5194/egusphere-egu22-1363, 2022.

The impact of the NASA DART spacecraft on the 160 m-diameter natural satellite called Dimorphos
of the binary asteroid 65803 Didymos on 26 September 2022 will change its orbital period around
Didymos. The change can be detected by Earth-based observers. Before impact, DART will deploy the Italian LICIACube that will
provide images of the first instants after impact. ESA’s Hera spacecraft will rendezvous Didymos four
years after the impact.

Hera will characterize in detail the properties of a Near-Earth Asteroid that are most relevant to
planetary defense:
•Measuring the mass of Dimorphos to determine the momentum transfer efficiency from DART
impact.
•Investigating in detail the crater produced by DART to improve our understanding of the cratering
process and the mechanisms by which the crater formation drives the momentum transfer
efficiency.
•Observing subtle dynamical effects (e.g. libration imposed by the impact, orbital and spin
excitation of Dimorphos) that are difficult to detect for remote observers.
•Characterising the surface and interior of Dimorphos to allow scaling of the momentum transfer
efficiency to different asteroids.

Hera will also provide unique asteroid science. It will rendezvous for the first
time with a binary asteroid. The secondary has a diameter of only 160 m, the smallest asteroid visited so far. Moreover, for the first time, internal and subsurface properties will be directly measured. From small asteroid internal and surface structures, through
rubble-pile evolution, impact cratering physics, to the long-term effects of space weathering in the
inner Solar System, Hera will have a major impact on many fields. How do binaries form? What is the surface composition of the asteroid pair? What are its internal properties?  What are the surface structure and regolith mobility on both Didymos and Dimorphos?
And what will be the size and the morphology of the crater left by DART? These questions and many others will be addressed by Hera as a natural outcome of its investigations focused on planetary defense.

How to cite: Küppers, M., Michel, P., Ulamec, S., Fitzsimmons, A., Green, S., Lazzarin, M., Carnelli, I., and Martino, P. and the The Hera Science Team: The ESA Hera mission to the binary asteroid (65803) Didymos:Planetary Defense and Science, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6375, https://doi.org/10.5194/egusphere-egu22-6375, 2022.

In 2019, Comet Interceptor was selected by the European Space Agency, ESA, as the first in its new class of F missions. The Japanese space agency, JAXA, is making a major contribution to the project. Comet Interceptor's primary science goal is to characterise for the first time, a yet-to-be-discovered long-period comet, preferably dynamically new, or an interstellar object. An encounter with a comet approaching the Sun for the first time will provide valuable data to complement information gathered by all previous comet missions, which through necessity all visited more evolved short period comets. The spacecraft will be launched in 2029 with the Ariel mission to the Sun-Earth Lagrange Point, L2. This relatively stable location allows a rapid response to the appearance of a suitable target comet, which will need to cross the ecliptic plane through an annulus centered on the Sun that contains Earth’s orbit. A suitable new comet would be searched for from Earth, with short period comets acting as mission backup targets. Powerful facilities such as the Vera Rubin Observatory make finding a suitable comet nearing the Sun very promising, and the spacecraft could encounter an interstellar object if one is found on a suitable trajectory. The spacecraft must cope with a wide range of target activity levels, flyby speeds, and encounter geometries. This flexibility has significant impacts on the spacecraft solar power input, thermal design, and dust shielding that can cope with dust impacts. Comet Interceptor comprises a main spacecraft and two probes, one provided by ESA, the other by JAXA, which will be released by the main spacecraft on approach to the target. The main spacecraft, which would act as the primary communication point for the whole constellation, would be targeted to pass outside the hazardous inner coma, making remote and in situ observations on the comet’s sunward side. Planned measurements of the target include its surface composition, shape, and structure, its dust environment, and the gas coma’s composition. A unique, multi-point ‘snapshot’ of the comet- solar wind interaction region will be obtained, complementing single spacecraft observations at other comets. We shall describe the science drivers, planned observations, and the mission’s instrument complement, to be provided by consortia of institutions in Europe and Japan.

How to cite: Jones, G., Snodgrass, C., and Tubiana, C. and the The Comet Interceptor Team: The Comet Interceptor Mission, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12656, https://doi.org/10.5194/egusphere-egu22-12656, 2022.

Cassini spacecraft investigated the Saturn environment more than 13 years. In course of this long period, the RPWS (Radio Plasma Wave Science) experiment not only mapped electric fields in the Saturn’s magnetosphere but also registered a large number of sharp spiky signals caused by hypervelocity dust impacts within Saturn rings. We have identified more than 140 000 such waveforms recorded by electric antennas with 10 or 80 kHz cadence in a close proximity of the ring mid-plane (up to 0.2 Rs). Among them, shapes and amplitudes of more than 100 000 non-saturated impacts were corrected on the Cassini WBR (Wide Band Receiver) transfer function.

Our laboratory experiment with the 1:20 reduced model of Cassini positioned in the test chamber of the dust accelerator allowed us to determine dependences of the signal shape and amplitude on the dust parameters (velocity and mass) and spacecraft potential. We apply these results on calculations of the mass and size distributions of dust particles detected by the electric field antennas within the Saturn ring system. The core of the paper is devoted to relation between dust characteristics (determined from impact signals and local plasma parameters) and ring mass profiles at distances ranging from 2 to 60 Rs from the surface.

How to cite: Nouzak, L., Pavlu, J., Vaverka, J., Safrankova, J., Nemecek, Z., Pisa, D., Shen, M., Sternovsky, Z., and Ye, S.: Saturn ring structure inferred from comparison of Cassini observations with laboratory simulations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1362, https://doi.org/10.5194/egusphere-egu22-1362, 2022.

Plasma Wave antenna instruments are employed on a range of space missions and can also be used to characterize the population of cosmic dust particles. Such measurements are complementary to those made by a dedicated dust instrument and suitable for the detection of larger (> 1 micron) particles. These booms or deployed wires with receiving elements are sensitive to the plasma cloud generated by the hypervelocity impact of a dust particle on the spacecraft, or the antenna itself. The dust impact is registered as a transient voltage signal (waveform) that is due to the charging of the spacecraft/antenna, and the induced charging from the part of the plasma cloud that is expanding from the impact location. Recent advancements provide the capability of obtaining the mass of the impacting particle from the measured waveforms. The new models are based on first principles and account for the parameters of the impact plasma (in terms of effective temperatures and the geometry of the expansion), the parameters of the ambient space environment, and the geometry of the spacecraft. The latter two allow for determining the approximate impact location on the spacecraft and thus constrain the incoming direction of the dust particle. Once the expansion of the transient impact plasma is over, the spacecraft and the antennas discharge through the ambient environment and relax back to their equilibrium potentials. The analysis of the measured waveforms thus also provides information on the density of the ambient plasma and its temperature. The numerical model is applied for the reanalysis of the measurements made by the STEREO spacecraft.

How to cite: Sternovsky, Z., Garzelli, A., Horanyi, M., Malaspina, D., Pokorny, P., and Juhasz, A.: Dust detection by antenna instruments with applications to the STEREO spacecraft, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10957, https://doi.org/10.5194/egusphere-egu22-10957, 2022.

Hypervelocity dust impacting the spacecraft body can be either partly or totally destroyed and evaporated and then creates a cloud of charged particles. Electrons and ions generated by such impacts can consequently influence the spacecraft potential and/or measurements of on-board scientific instruments. Electric field instruments are sensitive to these disturbances and typically register signals generated by dust impacts as short pulses. Once they are distinguished from other signals, they can be used for the detection of dust grains by spacecraft (even without dedicated dust detectors). 

Solar Orbiter is equipped with the RPW (Radio and Plasma Wave) instrument including three electric field antennas allowing such detection. The time domain sampler (TDS) subsystem of RPW provides typically short electric field waveforms (62.5 ms) sampled at a rate of 262.1 kHz

We have analyzed individual electric field waveforms of dust impacts detected by Solar Orbiter RPW/TDS and sorted into different categories (typical dust impact, impacts with the complex response, misinterpreted events, and suspicious events). Typical dust impacts are compared with an expected signal based on a model of dust impacts. The reliability of dust detection (fraction of misinterpreted and suspicious events) is evaluated with respect to the distance from the Sun.

How to cite: Vaverka, J., Pavlu, J., Nouzak, L., Safrankova, J., Nemecek, Z., Pisa, D., Soucek, J., Zaslavsky, A., and Maksimovic, M.: Dust Grain Detection by the Solar Orbiter Radio and Plasma Wave instrument, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1722, https://doi.org/10.5194/egusphere-egu22-1722, 2022.

Transient electric field perturbations are commonly observed when the interplanetary dust grains impact spacecraft, and their characteristics are well-studied. The signals are interpreted as due to the plasma expansion at the impact site and last typically in the order of micro-to milli-seconds. Radio and Plasma Wave (RPW) Instrument onboard Solar Orbiter can observe grains with a dedicated mode to capture such short-lived signals by the dust in the inner Heliosphere. On the other hand, a large impact can cause electric field disturbance for a longer time in tens of seconds. The long signals are observed in the low-frequency range (<10 kHz) and found more frequently during the inbound of the Solar Orbiter excursion. We will discuss the plasma and spacecraft conditions for the long durational impact signals.

How to cite: Morooka, M., Khotyaintsev, Y., Maksimovic, M., Soucek, J., and Pisa, D.: Very long electric field disturbances induced by dust impact observed by the Solar Orbiter/RPW, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11250, https://doi.org/10.5194/egusphere-egu22-11250, 2022.

We present results from automatic classification of dust waveforms observed by The Solar Orbiter Radio and Plasma Waves Instrument.

Every day, several dust particles impacts the Solar Orbiter as the probe travels trough the inner heliosphere. The dust impact produces a cloud of electrons and ions on the spacecraft surface and the free charge causes a sharp and characteristic voltage signal, which decays towards the equilibrium potential after a few milliseconds via interaction with the ambient plasma. Detection and analysis of the characteristic dust waveform can be used to map the density, size and velocity distribution of dust particles in the inner heliosphere, and thus enhance our understanding of the role of dust in the solar system. Such statistical analysis do however require reliable dust detection software.

It is challenging to automatically detect and separate dust waveforms from other signal shapes by "hard coded" algorithms. Both due to spacecraft charging, causing variable shapes of impact signals, and since electromagnetic waves (such as solitary waves) may induce resembling voltage signals. Here we present results of waveform classification using various supervised machine learning techniques, where manually classified data is used both to train and test the classifiers.

We investigate automatic machine learning classification as a possible tool to make statistical analysis of the distribution of dust in the inner heliosphere more reliable and easier to conduct. Furthermore, the classifier may possibly be used on data (after pre-processing) from other spacecrafts with similar instruments, such as the Parker Solar Probe (PSP), the Solar Terrestrial Relations Observatory (STEREO) and the Magnetospheric Multiscale (MMS) mission.

How to cite: Kvammen, A., Mann, I., and Kociscak, S.: Machine Learning Classification of Dust Impact Signals Observed by The Solar Orbiter Radio and Plasma Waves Instrument, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7995, https://doi.org/10.5194/egusphere-egu22-7995, 2022.

As the closest humanmade object to the sun, the Parker Solar Probe (PSP) is uniquely positioned to study inner heliospheric dust. The PSP/FIELDS instrument suite detects dust via short voltage pulses generated by the plasma clouds formed during hypervelocity dust impacts on the spacecraft. Similar dust detection methods have been used on other missions, including Voyager 1 and 2, STEREO, Wind, Cassini, and Solar Orbiter. In addition to the voltage signatures, about 2% of dust impacts captured by Time Domain Sampler (TDS) burst data on PSP/FIELDS are shown to have magnetic signatures measured by the high-frequency winding of PSP's Search Coil Magnetometer (SCM). While magnetic signatures have previously been detected in laboratory hypervelocity impact experiments, they have not been previously reported in space. The signatures are brief (lasting less than 0.1ms), and are associated with high-amplitude voltage signatures. In this work, we present statistics and case studies of dust impacts with magnetic signatures on PSP. We will discuss the TDS calibration required to interpret the measurements physically, along with potential physical mechanisms for the magnetic signatures. We will also present early modeling efforts and implications for future hypervelocity impact studies.

How to cite: Gasque, C., Bale, S., Bowen, T., Dudok de Wit, T., Geotz, K., Malaspina, D., Pusack, A., and Szalay, J.: Magnetic Signatures associated with Dust Impacts on Parker Solar Probe, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6496, https://doi.org/10.5194/egusphere-egu22-6496, 2022.

The zodiacal cloud is one of the largest structures in the solar system and strongly governed by meteoroid collisions near the Sun. Collisional erosion occurs throughout the zodiacal cloud, yet it has been historically difficult to directly measure. After transiting the inner-most regions of the solar system with Parker Solar Probe (PSP), we find that its dust impact rates are consistent with at least three distinct populations: bound zodiacal dust grains on elliptic orbits (α-meteoroids), unbound β-meteoroids on hyperbolic orbits, and a third population of impactors that may be either direct observations of discrete meteoroid streams or their collisional by-products (“β-streams”). The β-stream from the Geminids meteoroid stream is a favorable candidate for the third impactor population. β-streams of varying intensities are expected to be produced by all meteoroid streams, particularly in the inner solar system, and are a universal phenomenon in all exozodiacal disks. We discuss these recent PSP observations of the dust environment in the very inner solar system, provide constraints on their relative densities and fluxes, and discuss the erosion rate of zodiacal material.

These observations are also directly relevant for understanding the impactor and space weathering environment experienced by airless bodies in the inner solar system. Since the discovery of the Moon's asymmetric ejecta cloud, the origin of its sunward-canted density enhancement has not been well understood. Ejecta is produced from β-meteoroids which impact the Moon's sunward side at similar locations to this previously unresolved asymmetry. These small grains are submicron in size, comparable to or smaller than the lunar regolith particles they hit, and can impact the Moon at very high speeds ~100 km s^-1.  Incorporating β-meteoroid fluxes observed by the Pioneers 8 & 9, Ulysses, and Parker Solar Probe spacecraft as a newly considered impactor source at the Moon, we find β-meteoroid impacts to the lunar surface can explain the sunward asymmetry observed by LADEE/LDEX. We discuss these observations and how this finding suggests β-meteoroids may appreciably contribute to the evolution of other airless surfaces in the inner solar system.

How to cite: Szalay, J., Pokorný, P., Malaspina, D., Pusack, A., Horányi, M., DeLuca, M., Bale, S., Battams, K., Gasque, C., Goetz, K., Krüger, H., McComas, D., Schwadron, N., and Strub, P.: Collisional Evolution of the Inner Zodiacal Cloud: In-Situ observations from PSP and implications for Airless Body Surfaces, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10466, https://doi.org/10.5194/egusphere-egu22-10466, 2022.

The Yarkovsky and YORP effects originate due to the light pressure recoil force acting on the surface of an asteroid. The Yarkovsky effect changes the asteroid's orbit, whereas the YORP effect changes its rotation state. Both effects appear to be crucially important for the long-term evolution of kilometer-sized asteroids.

The talk will review the recent successes and difficulties in the theoretical modeling of these effects, the growing body of their observational confirmations, and how these effects can alter asteroids' shapes, create binary asteroids and asteroid pairs, spread asteroid families and help asteroids to migrate from the main belt to the near-Earth orbits.

How to cite: Golubov, O., Scheeres, D. J., and Krugly, Y. N.: Yarkovsky and YORP Effects: Theoretical Models, Observational Confirmations, and Implications for Asteroid Evolution, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12609, https://doi.org/10.5194/egusphere-egu22-12609, 2022.

In this work we present the main results of the project named ‘Meteor mathematical modelling of dark flight’ (MeMATH), and current state and future work related to our project. The MeMATH project started in September 2020.

The main objectives of the MeMATH project are:

i) numerical simulation of the dark-flight trajectory;

ii) determining the search area for meteorite fragments;

iii) the study of the ablation of large bodies.

In the first stage of the project, we developed a mathematical model for the dark flight trajectory of a meteoroid. The novelty of our model is that it considers the ellipsoidal shape of the Earth, the Coriolis effect and the centrifugal force.

In the current stage of the project, we are determining the ballistic coefficient α and the mass loss parameter β based on the meteoroid height and deceleration.

The α and β parameters have a great impact in the study of meteoroids from the identification of the parent body to determining the initial and final mass and finding out weather the remnant matter after ablation could result in a meteorite on the ground.

Acknowledgement.

The work of IB and MB was 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.

How to cite: Boaca, I. L., Gritsevich, M., Birlan, M., Nedelcu, A., and Boaca, T.: The interaction of meteoroids with the atmosphere, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8746, https://doi.org/10.5194/egusphere-egu22-8746, 2022.

On November 7, 2020, a bright fireball was observed over Sweden, and 13.8 kg iron meteorite was later recovered. Multiple observations of the fireball were conducted from Denmark, Finland, and Norway, making it the first instrumentally documented fall of an iron meteorite.

We used the instrumental recordings of the bolide to reconstruct its preatmospheric orbit, and studied the past orbital evolution of the meteoroid. We found no close affinity of the orbit of the meteoroid with any near-Earth asteroid. The long YORP timescale suggests that the meteoroid could have arrived intact from the main asteroid belt. Our analysis of the orbit shows that the meteoroid probably entered its near-Earth orbit via either the 𝜈6 secular resonance with Saturn or the 3:1 mean motion resonance with Jupiter.

The work was partially funded by the National Research Foundation of Ukraine (project N2020.02/0371).

How to cite: Golubov, O., Kyrylenko, I., Slyusarev, I., Visuri, J., Gritsevich, M., Krugly, Y. N., Belskaya, I., and Shevchenko, V. G.: Search for the parent body of the recently fallen iron meteorite, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12472, https://doi.org/10.5194/egusphere-egu22-12472, 2022.

            All-sky camera systems such as the AMOS network, record a large number of fireball events. By using multi-station triangulation method obtain information about trajectory of the body in the description change in altitude and velocity over time. Based on the characteristic of the object trajectory can determine important physical properties as the input mass of the meteoroid or the final mass of meteorites, and thus the probability of the formation and impact of particles on the Earth's surface. For this purpose, we used the method of dimensionless coefficients α (ballistic coefficient) and β (mass loss coefficient), which define the impact of the dynamical and physical properties of meteoroids on the searched input/final masses.

            Large number of recorded fireballs requires automatic data processing and their effective reduction. For this purpose, we have created a program with a user interface that works with data from all-sky fireballs cameras (in our case we focus on data from the Slovak AMOS system), defines the values of α-β coefficients and evaluates the probability of the meteorite formation with specific mass during the flight through the atmosphere. The program gives an interactive settings of physical parameters of the body and thus defines impact on the required values of body input/final masses. This algorithms was created for the purpose of user-friendly processing of scientific data, and the same time serves for the selecting suitable candidates for the formation and impact of dust particles and meteorites on the Earth's surface.

How to cite: Havrila, K., Gritsevich, M., and Tóth, J.: Identification of meteorite particles from AMOS data using the new user-friendly software interface., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6946, https://doi.org/10.5194/egusphere-egu22-6946, 2022.

Hydrothermal alteration is one of the fundamental processes by which several planetary bodies within our Solar System have been modified. The abundance of transient liquid water throughout the Solar System is increasingly recognised as playing a vital and active role in shaping the evolution of planetary surfaces. In particular, the process of hydrothermal alteration affects mineral composition on a microscopic level, simultaneously altering pre-existing minerals and allowing new mineral species to nucleate. This research reports new findings of fluid inclusions and their composition from one achondrite meteorite (Allan Hills A77256) and eight chondrite meteorites (Allan Hills 84029, Bells, Lonewolf Nunataks 94101 & 94102, Mighei, Santa Cruz, Sutter’s Mill, Sayama). We show that the presence of fluid inclusions within these meteorites is much more common than previously recognised, spanning much of the diversity of chondritic meteorite classes.

The first discovery of extraterrestrial liquid water was within halite crystals of the Zag and Monahans (1998) ordinary chondrites in 1999. Recent studies concerning extraterrestrial water and its evolution throughout the Solar System have attempted to gather inferences on the hydrothermal histories of parent asteroid bodies by utilising different proxies, including (but not limited to) magnetite grains, hydrous minerals, and degree of thermal metamorphism. These studies have highlighted a lack of direct water samples used within research and the need to determine whether further extraterrestrial liquid water fluid inclusions exist. Aside from those within the Zag and Monahans (1998) chondrites, additional claims of fluid inclusions within other meteorites have been previously reported. Until now, none have been independently confirmed or analysed further to determine whether or not they host liquid water.

Here we show that both petrographically primary and secondary in all our nine meteorites are hosted in olivine. Due to the formational nature of olivine, we predict that all petrographically primary fluid inclusions will fail to host liquid water. In contrast, petrographically secondary fluid inclusions may prove to be more plausible candidates. These inclusions are much more likely to possess liquid water as they were likely formed by subsequent and late periods of localised hydrothermal alteration, resulting in the serpentinisation of the host olivine crystals. Despite their predominance within our samples, in many cases, the analysis of secondary fluid inclusions is impeded by their sub-micron sizes and technological limitations of the instruments to operate at such a minuscule specimen size (< 1µm).

This research utilises a combination of SEM-EDS and Raman spectroscopy to target and determine the composition of the trapped fluids within suitable inclusions (diameter > 1µm). Spectra from initial Raman analyses conducted on selected fluid inclusions within olivine crystals of the Bells and Santa Cruz carbonaceous chondrites are presented. The majority of spectra from twenty-eight analysed fluid inclusions showed the fingerprint wavelength peak for olivine between 820-850 cm^-1 alongside an unanticipated discovery of several cosmic diamonds embedded deep within certain olivine grains at a wavelength peak of 1320-1360 cm^-1. This research highlights that numerous factors can affect the probability of a fluid inclusion hosting liquid water. 

How to cite: Krizan, P. A. B., H. -S. Chan, Q., Gough, A., and Papineau, D.: The hunt for liquid water in meteorites, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3872, https://doi.org/10.5194/egusphere-egu22-3872, 2022.