Meteoroid Population Research Articles

A reproducible method to determine the meteoroid mass index

Context. The determination of meteoroid mass indices is central to flux measurements and evolutionary studies of meteoroid populations. However, different authors use different approaches to fit observed data, making results difficult to reproduce and the resulting uncertainties difficult to justify. The real, physical, uncertainties are usually an order of magnitude higher than the reported values. Aims. We aim to develop a fully automated method that will measure meteoroid mass indices and associated uncertainty. We validate our method on large radar and optical datasets and compare results to obtain a best estimate of the true meteoroid mass index. Methods. Using MultiNest, a Bayesian inference tool that calculates the evidence and explores the parameter space, we search for the best fit of cumulative number vs. mass distributions in a four-dimensional space of variables ($a,b,X_1,X_2$). We explore biases in meteor echo distributions using optical meteor data as a calibration dataset to establish the systematic offset in measured mass index values. Results. Our best estimate for the average de-biased mass index for the sporadic meteoroid complex, as measured by radar appropriate to the mass range $10^{-3} > \mathrm{m} > 10^{-5}$ g, was $s=-2.10 \pm 0.08$. Optical data in the $10^{-1} > \mathrm{m} > 10^{-3}$ g range, with the shower meteors removed, produced $s=-2.08 \pm 0.08$. We find the mass index used by Grun et al. 1985 is substantially larger than we measure in the $10^{-4} < m < 10^{-1}$ g range.

Meteoroid environment on the transfer trajectories to Mars

The possibility of meteoroid impact is one of the main threats to the interplanetary missions. Although the meteoroids in the interplanetary space have very small masses, their velocities are extremely large and can produce highly energetic impacts. In this paper, a specific method to analyze the meteoroid environment on the transfer trajectories to Mars has been developed, by determination of the closest approach situation for a large sample of meteoroid orbits. This allows to analyze, not only the integral flux of meteoroids on the spacecraft surfaces, but also the specific kinematics for every single approach and the distributions of important variables such as relative velocity and its projections on specific directions such as instantaneous directions to Mars, Earth, Sun and apex. The obtained results give the quantitative and qualitative estimate of these variables which are separated for different populations of interplanetary meteoroids. The most exposed parts of the spacecraft on the Hohmann transfer to Mars are directed toward Mars, apex and anti-Earth point while the Sun and anti-Sun directions are symmetrically threatened. This gives the frame for the mission design and impact risk assessment and for the development of mathematical models of the behavior of the new spacecraft protection materials under impact loading and also for their experimental examination.

Microwave thermal emission from the zodiacal dust cloud predicted with contemporary meteoroid models

Predictions of the microwave thermal emission from the interplanetary dust cloud are made using several contemporary meteoroid models to construct the distributions of cross-section area of dust in space, and applying the Mie light-scattering theory to estimate the temperatures and emissivities of dust particles in broad size and heliocentric distance ranges. In particular, the model of the interplanetary dust cloud by Kelsall et al. (1998, ApJ 508: 44-73), the five populations of interplanetary meteoroids of Divine (1993, JGR 98(E9): 17,029-17,048) and the Interplanetary Meteoroid Engineering Model (IMEM) by Dikarev et al. (2004, EMP 95: 109-122) are used in combination with the optical properties of olivine, carbonaceous and iron spherical particles. The Kelsall model has been widely accepted by the Cosmic Microwave Background (CMB) community. We show, however, that it predicts the microwave emission from interplanetary dust remarkably different from the results of application of the meteoroid engineering models. We make maps and spectra of the microwave emission predicted by the three models assuming variant composition of dust particles. Predictions can be used to look for the emission from interplanetary dust in CMB experiments as well as to plan new observations.

The forthcoming EISCAT_3D as an extra-terrestrial matter monitor

It is important to monitor the extra-terrestrial dust flux in the Earth׳s environment and into the atmosphere. Meteoroids threaten the infrastructure in space as hypervelocity hits by micron-sized granules continuously degrade the solar panels and other satellite surfaces. Through their orbital elements meteoroids can be associated to the interplanetary dust cloud, comets, asteroids or the interstellar space. The ablation products of meteoroids participate in many physical and chemical processes at different layers in the atmosphere, many of them occurring in the polar regions.High-power large-aperture (HPLA) radars, such as the tristatic EISCAT UHF together with the EISCAT VHF, have been versatile instruments for studying many properties of the meteoroid population, even though they were not initially designed for this purpose. The future EISCAT_3D will comprise a phased-array transmitter and several phased-array receivers distributed in northern Scandinavia. These will work at 233MHz centre frequency with power up to 10MW and run advanced signal processing systems. The facility will in many aspects be superior to its predecessors as the first radar to combine volumetric-, aperture synthesis- and multistatic imaging as well as adaptive experiments. The technical design goals of the radar respond to the scientific requests from the user community. The VHF frequency and the volumetric imaging capacity will increase the collecting volume compared to the earlier UHF, the high transmitter power will increase the sensitivity of the radar, and the interferometry will improve the spatial resolution of the orbit estimates. The facility will be able to observe and define orbits to about 10% of the meteors from the established mass flux distribution that are large or fast enough to produce an ionization mantle around the impacting meteoroid within the collecting volume. The estimated annual mean of about 190000 orbits per day with EISCAT_3D gives many orders of magnitude higher detected orbit rates than the earlier tristatic UHF radar.

Instrumentally documented meteorite falls: two recent cases and statistics from all falls

AbstractPrecise data from instrumental observations of fireballs, especially those for really bright bolides, provide information about the population and physical properties of meteoroids, i.e. fragments of asteroids and comets, colliding with the Earth's atmosphere. An overview of what is known about meteoroids and their parent bodies from analysis of bolides producing meteorite falls, especially from the instrumentally observed meteorite falls, was a topic of this invited contribution. At present, atmospheric and orbital information with different degree of reliability and precision for these meteorite falls is known for only 24 cases. This topic was described in detail in the review work of Borovička, Spurný and Brown (2015) (Borovička et al., 2015). However, this work contains all instrumentally documented falls until end of 2013. To bring this work up to date, two new instrumentally observed meteorite falls in 2014, the Annama meteorite fall in Russia on 18 April 2014 and the Žďár nad Sázavou meteorite fall in the Czech Republic on 9 December 2014, are presented and commented in this paper. Especially the second case is mentioned in more detail including still unpublished data. Statistical analyses resulting from all 24 instrumentally documented falls are also mentioned.

Catalogue of representative meteor spectra

Aims. We present a library of low-resolution meteor spectra that includes sporadic meteors, members of minor meteor showers, and major meteor showers. These meteors are in the magnitude range from +2 to −3, corresponding to meteoroid sizes from 1 mm to 10 mm.Methods. Parallel double-station video observations allowed us to compute heliocentric orbits for all meteors. Most observations were performed during the periods of activity of major meteor showers in the years between 2006 and 2012. Spectra are classified according to relative intensities of the low-temperature emission lines of Mg, Na, and Fe.Results. Shower meteors were found to be of normal composition, except for Southern δ Aquariids and some members of the Geminid shower, neither of which have Na in the meteor spectra. Variations in Na content are typical for the Geminid shower. Three populations of Na-free mereoroids were identified. The first population are iron meteorites, which have an asteroidal-chondritic origin, but one meteoroid with low perihelion (0.11 AU) was found among the iron meteorites. The second population were Sun-approaching meteoroids in which sodium is depleted by thermal desorption. The third population were Na-free meteoroids of cometary origin. Long exposure to cosmic rays on the surface of comets in the Oort cloud and disintegration of this crust might be the origin of this population of meteoroids.

RADAR DETECTABILITY STUDIES OF SLOW AND SMALL ZODIACAL DUST CLOUD PARTICLES. II. A STUDY OF THREE RADARS WITH DIFFERENT SENSITIVITY

The sensitivity of radar systems to detect different velocity populations of the incoming micrometeoroid flux is often the first argument considered to explain disagreements between models of the Near-Earth dust environment and observations. Recently, this was argued by Nesvorný et al. to support the main conclusions of a Zodiacal Dust Cloud (ZDC) model which predicts a flux of meteoric material into the Earth's upper atmosphere mostly composed of small and very slow particles. In this paper, we expand on a new methodology developed by Janches et al. to test the ability of powerful radars to detect the meteoroid populations in question. In our previous work, we focused on Arecibo 430 MHz observations since it is the most sensitive radar that has been used for this type of observation to date. In this paper, we apply our methodology to two other systems, the 440 MHz Poker Flat Incoherent Scatter Radar and the 46.5 Middle and Upper Atmosphere radar. We show that even with the less sensitive radars, the current ZDC model over-predicts radar observations. We discuss our results in light of new measurements by the Planck satellite which suggest that the ZDC particle population may be characterized by smaller sizes than previously believed. We conclude that the solution to finding agreement between the ZDC model and sensitive high power and large aperture meteor observations must be a combination of a re-examination not only of our knowledge of radar detection biases, but also the physical assumptions of the ZDC model itself.

Characterization and Analysis of Near-Earth Objects via Lunar Impact Observations

Asteroid events such as the air blast above Chelyabinsk, Russia, in the spring of 2013 have highlighted the importance of understanding Earth's local asteroid population and the potential threat they pose. While much observational data exists for larger asteroids (those greater than 50 meters in diameter), comparatively little is known of the very small meteoroid population. This study utilized the non-illuminated part of the near side of the Moon as a detection screen upon which the faint flashes of small meteoroids hitting the lunar surface could be detected. Over 80 hours of observations were conducted between the fall of 2010 and the spring of 2013. The observed lunar area was determined nightly and used alongside the impact count to determine a meteoroid flux rate. Impact flashes were calibrated to extinction and color corrected reference stars to estimate the kinetic energies involved. Analysis indicated an average flux rate of 1.09×10−7km−2h−1, corresponding to 1 impactor larger than 3 centimeters in diameter observed every 30 minutes. Further, the size distribution dependence of small impactors was found to be consistent with the power law governing the larger-size meteoroid distribution. This data helps fix the low-end of the asteroid size distribution for solar system evolution models.

A population of small refractory meteoroids in asteroidal orbits

More than 7000 two-station meteors observed with two different video systems, both parts of the Canadian Automated Meteor Observatory, have been analysed. The more sensitive (limiting magnitude +6.5) influx system shows a significant population of slow meteors with begin heights under 86km, while the less sensitive (limiting magnitude +4) tracking system shows many more fast meteors ablating at high altitudes. The low, slow population has asteroidal orbits with low inclinations and moderate eccentricities, and radiants which are not, in general, associated with the sporadic sources. In spite of their low begin heights, which imply that they are strong and refractory, the meteors have early peaked light curves which are not predicted by classical ablation theory for non-fragmenting objects.

First 3‐D simulations of meteor plasma dynamics and turbulence

AbstractMillions of small but detectable meteors hit the Earth's atmosphere every second, creating trails of hot plasma that turbulently diffuse into the background atmosphere. For over 60 years, radars have detected meteor plasmas and used these signals to infer characteristics of the meteoroid population and upper atmosphere, but, despite the importance of meteor radar measurements, the complex processes by which these plasmas evolve have never been thoroughly explained or modeled. In this paper, we present the first fully 3‐D simulations of meteor evolution, showing meteor plasmas developing instabilities, becoming turbulent, and inhomogeneously diffusing into the background ionosphere. These instabilities explain the characteristics and strength of many radar observations, in particular the high‐resolution nonspecular echoes made by large radars. The simulations reveal how meteors create strong electric fields that dig out deep plasma channels along the Earth's magnetic fields. They also allow researchers to explore the impacts of the intense winds and wind shears, commonly found at these altitudes, on meteor plasma evolution. This study will allow the development of more sophisticated models of meteor radar signals, enabling the extraction of detailed information about the properties of meteoroid particles and the atmosphere.

Meteor trail characteristics observed by high time resolution lidar

Abstract. We report and analyse the characteristics of 1382 meteor trails based on a sodium data set of ~ 680 h. The observations were made at Yanqing (115.97° E, 40.47° N), China by a ground-based Na fluorescence lidar. The temporal resolution of the raw profiles is 1.5 s and the altitude resolution is 96 m. We discover some characteristics of meteor trails different from those presented in previous reports. The occurrence heights of the trails follow a double-peak distribution with the peaks at ~ 83.5 km and at ~ 95.5 km, away from the peak height of the regular Na layer. 4.7% of the trails occur below 80 km, and 3.25% above 100 km. 75% of the trails are observed in only one 1.5 s profile, suggesting that the dwell time in the laser beam is not greater than 1.5 s. The peak density of the trails as a function of height is similar to that of the background sodium layer. The raw occurrence height distribution is corrected taking account of three factors which affect the relative lifetime of a trail as a function of height: the meteoroid velocity (which controls the ratio of Na/Na+ ablated); diffusional spreading of the trail; and chemical removal of Na. As a result, the bi-modal distribution is more pronounced. Modelling results show that the higher peak corresponds to a meteoroid population with speeds between 20 and 30 km s−1, whereas the lower peak should arise from much slower particles in a near-prograde orbit. It is inferred that most meteoroids in this data set have masses of ~ 1 mg, in order for ablation to produce sufficient Na atoms to be detected by lidar. Finally, the evolution of longer-duration meteor trails is investigated. Signals at each altitude channel consist of density enhancement bursts with the growth process usually faster than the decay process, and there exists a progressive phase shift among these altitude channels.

Simulation of the capabilities of an orbiter for monitoring the entry of interplanetary matter into the terrestrial atmosphere

In comparison with existing ground-based camera networks for meteors monitoring, a space-based optical system would escape dependency on weather and atmospheric conditions and would offer a wide spatial coverage and an unrestricted and extinction-free spectral domain. The potential rates of meteor detections by such systems are evaluated in this paper as a function of observations parameters (optical system capabilities, orbital parameters) and considering a reasonable range of meteoroids properties (e.g., mass, velocity, composition) determining their luminosity. A numerical tool called SWARMS (Simulator for Wide Area Recording of Meteors from Space) has been developed. SWARMS is also intended to be used in an operational phase to facilitate the comparison of observations with up-do-date constraints on the flux and characteristics of the interplanetary matter entering our planet׳s atmosphere. The laws governing the conversion of a fraction of the meteor kinetic energy into radiation during atmospheric entry have been revisited and evaluated based on an analysis of previously published meteor trajectories. Rates of detection were simulated for two different systems: the SPOSH (Smart Panoramic Optical Sensor Head) camera optimized for the observation of transient luminous events, and the JEM-EUSO (Japanese Experiment Module-Extreme Universe Space Observatory) experiment on the ISS (International Space Station). We conclude that up to 6 events per hour in the case of SPOSH, and up to 0.67 events in the case of JEM-EUSO may be detected. The optimal orbit for achieving such rates of detections depends on the mass index of the meteoroid populations. The determination of this parameter appears therefore critical before an optimal orbiting system might be designed for meteors monitoring.

Rotation of cometary meteoroids

The aim of this study is to estimate the rotational characteristics of meteoroids after their release from a comet during normal activity. The results can serve as initial conditions for further analyses of subsequent evolution of rotation in the interplanetary space. A sophisticated numerical model was applied to meteoroids ejected from 2P/Encke comet. The meteoroid shapes were approximated by polyhedrons with several thousands of surface elements, which have been determined by 3D laser scanning method of 36 terrestrial rock samples. These samples came from three distinct sets with different origin and shape characteristics. Two types of gas-meteoroid interactions (diffuse and specular reflection of gas molecules from the surface of meteoroid) and three gas ejection models (leading to very different ejection velocities) were assumed. The rotational characteristics of ejected meteoroid population were obtained by numerical integration of equations of motion with random initial conditions and random shape selection. It was proved, that the results do not depend on specific set of shape models and that they are applicable to (unknown) shapes of real meteoroids. A simple relationship between median of meteoroid spin frequencies $\bar{f}$ (Hz), ejection velocities $v_{\rm ej}$ (m s$^{-1}$) and sizes $D$ (m) was determined. For diffuse reflection of gas molecules from meteoroid's surface it is: $\bar{f}\simeq 2\times 10^{-3} v_{\rm ej} D^{-0.88}$, and for specular reflection of gas molecules from meteoroid's surface it is: $\bar{f}\simeq 5\times 10^{-3} v_{\rm ej} D^{-0.88}$. The distribution of spin frequencies is relatively wide; $2\sigma$-interval can be described as $\sim(0.1, 10)\times \bar{f}$. The results were determined for 2P/Encke comet, but it was shown that their validity is general.

DYNAMICAL MODEL FOR THE TOROIDAL SPORADIC METEORS

More than a decade of radar operations by the Canadian Meteor Orbit Radar have allowed both young and moderately old streams to be distinguished from the dispersed sporadic background component. The latter has been categorized according to broad radiant regions visible to Earth-based observers into three broad classes: the helion and anti-helion source, the north and south apex sources, and the north and south toroidal sources (and a related arc structure). The first two are populated mainly by dust released from Jupiter-family comets and new comets. Proper modeling of the toroidal sources has not to date been accomplished. Here, we develop a steady-state model for the toroidal source of the sporadic meteoroid complex, compare our model with the available radar measurements, and investigate a contribution of dust particles from our model to the whole population of sporadic meteoroids. We find that the long-term stable part of the toroidal particles is mainly fed by dust released by Halley type (long period) comets (HTCs). Our synthetic model reproduces most of the observed features of the toroidal particles, including the most troublesome low-eccentricity component, which is due to a combination of two effects: particles' ability to decouple from Jupiter and circularize by the Poynting-Robertson effect, and large collision probability for orbits similar to that of the Earth. Our calibrated model also allows us to estimate the total mass of the HTC-released dust in space and check the flux necessary to maintain the cloud in a steady state.

The flux of kilogram-sized meteoroids from lunar impact monitoring

The flashes from meteoroid impacts on the Moon are useful in determining the flux of impactors with masses as low as a few tens of grams. A routine monitoring program at NASA’s Marshall Space Flight Center has recorded over 300 impacts since 2006. A selection of 126 flashes recorded during periods of photometric skies was analyzed, creating the largest and most homogeneous dataset of lunar impact flashes to date. Standard CCD photometric techniques were applied to the video and the luminous energy, kinetic energy, and mass are estimated for each impactor. Shower associations were determined for most of the impactors and a range of luminous efficiencies was considered. The flux to a limiting energy of 2.5×10−6kT TNT or 1.05×107J is 1.03×10−7km−2h−1 and the flux to a limiting mass of 30g is 6.14×10−10m−2yr−1 at the Moon. Comparisons made with measurements and models of the meteoroid population indicate that the flux of objects in this size range is slightly lower (but within the error bars) than flux at this size from the power law distribution determined for the near Earth object and fireball population by Brown et al. (Brown, P.G., Spalding, R., ReVelle, D., Tagliaferri, E., Worden, S. [2002]. Nature 420, 294–296). Size estimates for the crater detected by Lunar Reconnaissance Orbiter from a large impact observed on March 17, 2013 are also briefly discussed.

The Geminid meteoroid stream as a potential meteorite dropper: a case study

A Geminid fireball with an absolute magnitude of -13 was observed over the south of Spain on Dec. 15, 2009. This extraordinarily bright event (the brightest Geminid ever recorded by our team) was imaged from two meteor observing stations operated by the SPanish Meteor Network (SPMN). The bolide exhibited fast and quasi-periodic variations in brightness, a behaviour typically associated to the rotation of the parent meteoroid. The inferred tensile strength of this particle was found to be significantly higher that the typical values obtained for Geminid meteoroids. The fireball penetrated in the atmosphere till a final height of about 25 km above the ground level and a non-zero terminal mass was calculated at the ending point of the luminous trajectory. In this way, the observational evidence points to the existence of a population of meteoroids in the higher end of the Geminid mass distribution capable of producing meteorites. From the relative chemical abundances inferred from the emission spectrum of this bolide we conclude that the Geminid-forming materials are similar to some primitive carbonaceous chondrite groups. Then, we conclude that in meteorite collections from cold deserts, capable to preserve meteorites of few tens of grams, some rare groups of carbonaceous chondrites could be coming from the Geminid parent body: (3200) Phaeton.

The meteoroid environment and impacts on Phobos

We review current knowledge of the flux of meteoroids on Phobos, a key to interpreting its cratering record and understanding the origin of the Martian satellite system. Past observational attempts to estimate the flux of small (mm to cm) meteoroids as meteors in the Martian atmosphere highlight the need for customised instrumentation onboard future missions bound for Mars. The temporal distribution of cometary meteoroid streams as predicted by recent work is non-uniform; we advocate emplacing seismic stations on Phobos or cameras optimised to monitor the Martian atmosphere for meteors as a means to elucidate this and other features of the meteoroid population. We construct a model of the sporadic flux of metre-sized or larger meteoroids and use it to predict a leading/trailing ratio in crater density of ~4 if crater production by asteroidal meteoroids dominates over that by cometary ones. It is found that the observed distribution of craters ≥100m as determined from spacecraft images is consistent with a 50/50 contribution from the two meteoroid populations in our model. A need for more complete models of the meteoroid flux is identified. Finally, the prospects for new observational constraints on the meteoroid environment are reviewed.

Small meteoroids’ major contribution to Mercury’s exosphere

The contribution of the meteoroid population to the generation of Mercury’s exosphere is analyzed to determine which segment contributes most greatly to exospheric refilling via the process of meteoritic impact vaporization. For the meteoroid data, a differential mass distribution based on work by Grün et al. (Grün, E., Zook, H.A., Fechtig, H., Giese, R.H. [1985]. Icarus 62(2), 244–272) and a differential velocity distribution based on the work of Zook (Zook, H.A. [1975]. In: 6th Lunar Science Conference, vol. 2. Pergamon Press, Inc., Houston, TX, pp. 1653–1672) is used. These distributions are then evaluated using the method employed by Cintala (Cintala, M.J. [1992]. J. Geophys. Res. 97(E1), 947–974) to determine impact rates for selected mass and velocity segments of the meteoroid population.The amount of vapor created by a single meteor impact is determined by using the framework created by Berezhnoy and Klumov (Berezhnoy, A.A., Klumov, B.A. [2008] Icarus, 195(2), 511–522). By combining the impact rate of meteoroids with the amount of vapor a single such impact creates, we derive the total vapor production rate which that meteoroid mass segment contributes to the Herman exosphere. It is shown that meteoroids with a mass of 2.1×10−4g release the largest amount of vapor into Mercury’s exosphere. For meteoroids in the mass range of 10−18g to 10g, 90% of all the vapor produced is due to impacts by meteoroids in the mass range 4.2×10−7g⩽m⩽8.3×10−2g.

Frequency of hyperbolic and interstellar meteoroids

AbstractHyperbolic meteor orbits from the catalog of 64,650 meteors observed by the multistation video meteor network located in Japan (SonotaCo 2009) have been investigated with the aim of determining the relation between the frequency of hyperbolic and interstellar meteors. The proportion of hyperbolic meteors in the data decreased significantly (from 11.58% to 3.28%) after a selection of quality orbits, which shows its dependence on the quality of observations. Initially, the hyperbolic orbits were searched for meteors unbound due to planetary perturbation. It was determined that 22 meteors from the 7489 hyperbolic orbits in the catalog (and 2 from the selection of the orbits with the highest quality) had had a close encounter with a planet, none of which, however, produced essential changes in their orbits. Similarly, the fraction of hyperbolic orbits in the data, which could be hyperbolic by reason of a meteor's interstellar origin, was determined to be at most 3.9 × 10−2. From the statistical point of view, the vast majority of hyperbolic meteors in the database have definitely been caused by inaccuracy in the velocity determination. This fact does not necessarily assume great measurement errors, since, especially near the parabolic limit, a small error in the value of the heliocentric velocity of a meteor can create an artificial hyperbolic orbit that does not really exist. The results show that the remaining 96% of meteoroids with apparent hyperbolic orbits belong to the solar system meteoroid population. This is also supported by their high abundance (about 50%) among the meteor showers.

The Meteoroid Input Function and predictions of mid-latitude meteor observations by the MU radar

The majority of extraterrestrial particles entering Earth’s atmosphere originate from the Sporadic Meteoroid Complex (SMC) and are associated with many mesospheric layer phenomena. The Meteoroid Input Function (MIF) is a model that has been developed with the purpose of understanding the temporal and spatial variability of the meteoroid impact in the atmosphere. The MIF has been shown to accurately predict the seasonal and diurnal variations of the meteor flux observed by High Power Large Aperture (HPLA) radars at various geographic locations, including the Arecibo Observatory (AO) and the Poker Flat Incoherent Scatter Radar (PFISR). For this, the model requires the assessment of a potential observational bias of the particular HPLA radar utilized: the minimum detectable radar cross-section (RCS). The RCS sensitivity threshold provides a metric to characterize the radar system’s ability to detect particles with a given mass and speed. In this paper, the MIF model was used to predict meteor properties (e.g. the distributions of areal density, speed, and radiant location) observed by the Middle and Upper atmosphere (MU) radar while leveraging the system’s interferometric capability to address the model’s ability to predict meteor observations at middle geographic latitudes and for a radar operating frequency in the low VHF band. This study demonstrates that the MIF accurately considered the speed and sporadic source distributions for the portion of the meteoroid population observable by the MU radar, and the applicability of the MIF to the MU system increases the confidence of using it as a global model.