An electrodynamics model for Data Interpretation and Numerical Analysis of ionospheric Missions and Observations (DINAMO)

We introduce a new numerical model developed to assist with Data Interpretation and Numerical Analysis of ionospheric Missions and Observations (DINAMO). DINAMO derives the ionospheric electrostatic potential at low- and mid-latitudes from a two-dimensional dynamo equation and user-specified inputs for the state of the ionosphere and thermosphere (I–T) system. The potential is used to specify the electric fields and associated F-region E × B plasma drifts. Most of the model was written in Python to facilitate the setup of numerical experiments and to engage students in numerical modeling applied to space sciences. Here, we illustrate applications and results of DINAMO in two different analyses. First, DINAMO is used to assess the ability of widely used I–T climatological models (IRI-2016, NRLMSISE-00, and HWM14), when used as drivers, to produce a realistic representation of the low-latitude electrodynamics. In order to evaluate the results, model E × B drifts are compared with observed climatology of the drifts derived from long-term observations made by the Jicamarca incoherent scatter radar. We found that the climatological I–T models are able to drive many of the features of the plasma drifts including the diurnal, seasonal, altitudinal and solar cycle variability. We also identified discrepancies between modeled and observed drifts under certain conditions. This is, in particular, the case of vertical equatorial plasma drifts during low solar flux conditions, which were attributed to a poor specification of the E-region neutral wind dynamo. DINAMO is then used to quantify the impact of meridional currents on the morphology of F-region zonal plasma drifts. Analytic representations of the equatorial drifts are commonly used to interpret observations. These representations, however, commonly ignore contributions from meridional currents. Using DINAMO we show that that these currents can modify zonal plasma drifts by up to ~ 16 m/s in the bottom-side post-sunset F-region, and up to ~ 10 m/s between 0700 and 1000 LT for altitudes above 500 km. Finally, DINAMO results show the relationship between the pre-reversal enhancement (PRE) of the vertical drifts and the vertical shear in the zonal plasma drifts with implications for equatorial spread F.

Preface to the special issue of the Division Energy, Resources and the Environment at vEGU2021: Gather online​​​​​​​

The European Geosciences Union (EGU) is one of the leading global bottom-up societies that promotes earth, planetary and space sciences. In its annual general assemblies, EGU brings together experts from all over the world to discuss cutting-edge research and implementation of findings in its respective disciplines and thus offers a unique forum for scientific exchange, science-policy interaction, and joint development of strategies for future research endeavours. This special issue in Advances in Geosciences comprises a collection of contributions from the Division Energy, Resources and the Environment (ERE) of the EGU, which were presented at the General Assembly 2021, vEGU2021: Gather online. It was held entirely online for the second time after EGU2020 from 19 to 30 April 2021.

Astrotheology’s contribution to public theology: From the extraterrestrial intelligence myth to astroethics

Public theology is conceived in the church, reflected on critically in the academy and addressed to the world for the sake of the world. The development of a theology of nature is included in the public theologian’s list of tasks of nature that is scripturally based and heavily informed by the natural sciences. Astrotheology is one product. Astrotheology engages astrobiology and other space sciences, firstly, by critically exposing the extraterrestrial intelligence (ETI) myth at the heart of science and secondly, by partnering in thinking through public policy proposals with astroethicists.Contribution: The HTS collection on ‘Theology and Nature’ sparks theological discussion both within and beyond the church. By developing the fields of astrotheology and astroethics, this article contributes to a ‘Theology of Nature’ as an exercise in Public Theology.

Women in Astronomy in Belgium

<p>We are attempting to gather all information available to study the question of the representation of women in astronomy in Belgium, which is not a straightforward task.</p> <p>In an early study, [1] analysed gender-specific statistics on the Belgian physicists. One of the difficulties they found was that Belgium keeps different statistics for the French-speaking and Flemish universities, and the career structure is different depending on the Communities.</p> <p>As preliminary analysis, we investigated the percentage of women in the International Astronomical Union (IAU) registered in the database for Belgium [2]. The IAU is an international organization with participation from 68 countries that covers the main areas of astronomy, including planetary science. In 2021, 32 out of 144 Belgian members were female (22%). It is important to notice that not all astronomers in Belgium, and in particular not the younger generation where the percentage of female researchers is higher, are member of IAU. Therefore we expect these values to underestimate the true number of women in the field. In view of the fact that it is the same at the level of the funding bodies and, by construction, at the universities, Earth and Space Sciences will be considered together. We will present preliminary results of our study.</p> <p><strong>References:</strong></p> <p>[1] Petra Rudolf, Vice‐President, Christine Iserentant, Muriel Vander Donckt, Nathalie Balcaen, Peggy Fredrickx, Karen Janssens, and Griet Janssen, "Women in Physics in Belgium: Still a Long Way From Achieving Gender Equality", AIP Conference Proceedings 628, 131-132 (2002) https://doi.org/10.1063/1.1505297</p> <p>[2] https://www.iau.org/administration/membership/individual/distribution/</p>

Measurement of Titan’s surface permittivity with the DraGMet/DIEL sensor on Dragonfly

<p>Titan, Saturn’s biggest moon, is an ocean world, covered by organic materials and therefore one of the most promising astrobiological target in the Solar System, likely holding clues on the origin of life on Earth. That is why NASA has selected the Dragonfly mission to send in 2027 a rotorcraft lander to Titan and investigate its prebiotic chemistry and habitability.</p> <p> </p> <p>Making multiple flights (up to 24 in 2.5 years, starting in 2034), Dragonfly will explore a variety of locations, from the Shangri-La dune field to the rim of the young impact crater Selk (Lorenz et al., 2018), and therefore sample materials and determine surface properties in different geologic settings. The two permittivity probes - called DIEL- on board the Geophysical and Meteorological package (DraGMet) will be especially useful to characterize Dragonfly landing site environment.</p> <p> </p> <p>DIEL<strong> </strong>consist of 2 electrodes acting as self-impedance permittivity probes. They will be mounted on each skid of the Dragonfly rotorcraft and operate independently for sake of redundancy and safety. Their objective is to measure the complex ground permittivity at several low frequencies (<10 kHz) which will provide clues on the composition, moisture and porosity of the near-subsurface of Titan as well as on the spatial and temporal variations of such properties. As a reminder, the first permittivity probe on Titan (actually the first ever planetary permittivity probe) successfully determined the complex permittivity of the Huygens landing site in 2005 (Grard et al, 2006; Hamelin et al. 2016).</p> <p> </p> <p>During this presentation, we will describe the tests that have been performed on prototypes of the DIEL electrode plates in order to estimate their sounding depth and sensitivity to composition variations. Tests were performed e.g., with the electrode lying on reference plastic slabs and natural materials (air, sand, soil, liquid water, etc.) of well-known complex permittivity, at ambient and Titan temperatures. The effect of porosity and of a bad ground-electrode contact was also investigated leading to suggestions to optimize DIEL electrode design, accommodation and performance.</p> <p> </p> <p>Indeed, the design of the DIEL experiments (size, shape, accommodation of the electrodes, modes of operation ect.) is not frozen yet and we are also conducting modelling simulations with COMSOL Multiphysics © to explore possible better designs and confirm the results obtained in laboratory.</p> <p> </p> <p>Lastly, in order to relate DIEL measurements to the ground composition, it is crucial to know the electrical properties of materials relevant to Titan’s surface. This is the purpose of the PAP (Permittivité d’Analogues Planétaires) measurement bench that have been developed at LATMOS. This bench includes a cryostat to perform measurements at Titan’s temperature (90 K). It was successfully used to investigate the complex permittivity of analogs of Titan’s organic aerosols called “tholins” (Lethuillier et al., 2018). Future measurements will focus on “eroded” tholins, that is tholins that have been modified during their descent to the surface by processes analogous to those at play in Titan’s atmosphere: UV radiations (Carrasco et al., 2018), interaction with ionosphere’s charged particles (Chatain et al., 2020), deposition of ice in the low stratosphere (Fleury et al., 2019; Dubois et al., 2020), wetting by droplets of liquid methane in the troposphere etc.</p> <p> </p> <p><strong>References</strong></p> <p>Beghin et al., <em>Icarus</em> 218 (2012)</p> <p>Carrasco et al., Nature Astronomy, Nature Publishing Group (2018)</p> <p>Chatain et al., Icarus 345 (2020)</p> <p>Dubois et al., Icarus 338 (2016)</p> <p>Hamelin et al., Icarus 270 (2016)</p> <p>Grard et al., Planet. Space Sciences 54 (2006)</p> <p>Fleury et al., Icarus 321 (2019)</p> <p>Lethuillier et al., Astronomy & Astrophysics 519 (2018)</p> <p>Lorenz et al., <em>Johns Hopkins APL Technical Digest</em> 34 (2018)</p> <p> </p>

Status of space science and planetary sciences in Uganda: Building it through synergies with Europe

<p>Space Science and Astrophysics are currently emerging fields in most African countries and in particular Uganda. These two fields are known to be channels of socioeconomic development and as such need to be developed further in the different African countries. For this to be achieved, there is need to deal with the challenges in doing astronomy or space science research on the African continent for instance access to state of the art computational and observational facilities. Creating synergies between European and African countries offers a gateway to advancing astronomy in Africa. In East Africa, and in particular Uganda, Mbarara University of Science and Technology (MUST) is aiming at becoming a centre of excellence in Space Science and Astrophysics research. This has been possible through the funding from the Swedish International Development Agency through the International Science Programme at Uppsala University.<br />I will briefly highlight the different projects going on at MUST in both Planetary and Space sciences. I will then focus on the results obtained in our study on “stellar activity as an important factor for planet habitability”. This study was carried out in collaboration with the Thueringer Landessternwarte-Tautenburg, Germany.</p>