bluuebunny/crossref_metadata_2025 huggingface dataset:
Pre-perihelion high resolution optical spectroscopy of the long period comet C/2017 K2 (PanSTARRS) with UVES at the VLT
Authors: Jehin Emmanuel , Lippi Manuela , Hutsemékers Damien , Manfroid Jean , Vander Donckt Mathieu , Rousselot Philippe
Published: September 2022

The long-period comet C/2017 K2 (PanSTARRS) was discovered in 2017 at a large heliocentric distance of 16 au (Wainscoat et al. 2017). Pre-discovery images from 2013 show that K2 was even active at a record distance of ~24 au from the Sun (Jewitt et al. 2017) well beyond the snow line, indicating that, most probably, CO and CO2 ices - the most abundant species after water - might drive its activity. CO was indeed detected in K2’s coma in the sub-mm range at a heliocentric distance of 6.7 au (Yang et al. 2021) and K2 was claimed to be a CO-rich comet.

Detecting comets at such large distances is becoming more frequent, but it is still a rare occasion to study a well preserved comet surface coming directly from the Oort Cloud or on a several million years orbit, and especially if it is of a rare type. 
K2 will reach its perihelion on 2022 December 19 (Rh=1.8 au, Δ=2.5 au) and become a bright target in automn with good observing conditions from the Southern hemisphere. We have started an observing campaign on May 8 (Rh=3.2 au), 2022 with UVES at the ESO VLT to obtain high resolution and good SNR optical spectra to characterize the detailed coma composition of its daughter species before and after K2 perihelion. We report here about the first epochs before perihelion.

UVES was setup with a slit width of 0.45" (length of 10") to provide a resolving power of 80.000, and we selected two different settings (DIC#1 346/580 and DIC2 437/860) to cover the whole optical range (304-1040 nm) at each epoch in only two long exposures on the same night. These spectra will allow us to compare K2 - characterized by its unusual distant activity - to other well studied comets in the optical and particularly using the same instrument since 20 years by the Liège comet team. These spectra will allow us to measure the detailed composition of its coma: the production rates of the daughter species (OH, CN, C2 etc.) to check among other things if the comet is a C-chain depleted or normal comet (A'Hearn et al. 1995), to link those production rates with those from the parent species observed in the IR (see CRIRES+ poster by Lippi et al.), to search for CO+ and CO2+ lines to check if K2 is a CO-rich comet like the unique CO-N2-rich blue comet C/2016 R2 (PanSTARRS) (Opitom et al. 2019), to measure the ratio of the [OI] lines to estimate the CO/H2O ratio (Decock et al. 2015), and if the comet is bright enough to measure the isotopic ratios of the light elements (12C/13C and 14N/15N from the CN isotopologues), to measure the ortho- to para- ratio of NH2, and search for faint FeI and NiI lines which are a new and puzzling component of the cometary coma (Manfroid et al. 2021).
Impact of growing planets on the evolution of protoplanetary disks
Authors: Ringseis Ines
Published: September 2022

The protoplanetary disk (PPD) is a complex structure. It is the birth place of protoplanetary systems. The interaction of growing planets and its surrounding PPD is also complex and not fully understand by now. The many different physical processes going on in the PPD over its life time, like accretion, outbursts, planet formation, etc. impact its evolution and structure. The evolution of such a PPD with a growing planet, implemented as a sink term, is simulated by the TAPIR code.  It is an 1+1D implicit code. Due to the fact that TAPIR is an implicit code the time steps are not restricted by the CFL-conditions, therefore it is able to simulate over the whole lifetime of a PPD and examine the evolutionary behaviour of the protoplanetary disk and the influence of a forming protoplanet on it. The results show the gap formation due to mass accretion onto the planet and impact of this sink term on the total disk mass, disk lifetime and accretion rat onto the star. Also the impact of accretion bursts on the accretion rate of the planet is discussed. If the planet is placed in the dead zone the presence of outbursts leads to a quite faster planet growth since the bursts rearranges the disk structure.
A comparison of novel algorithms for unbiased recovery of extended disk signals with ADI - Application to the case of MWC 758 and its protoplanet candidates.
Authors: Christiaens Valentin , Pairet Benoit , Juillard Sandrine , Calcino Josh , Baruteau Clément
Published: September 2022

With its large sub-mm continuum cavity, asymmetric clumps and spiral arms, the disc of MWC 758 is an ideal test laboratory to search for embedded planets at an early stage of formation and study their dynamical interplay with the disc. As such, two protoplanet candidates have been proposed in this disc by independent teams based on thermal IR high-contrast imaging data, which both require confirmation. In this contribution, I will compare three novel algorithms that we designed to alleviate current shortcomings stemming from the application of state-of-the-art Angular Differential Imaging (ADI)-based algorithms - namely geometric biases induced to azimuthally extended signals from the aggressive modeling and subtraction of the stellar halo. The first algorithm relies on an iterative approach, while the other two rely on an inverse-problem approach, with and without regularisation terms, respectively, to recover the unbiased circumstellar intensity distribution. I will show the images obtained from the application of these algorithms to the case of MWC 758, for which we considered the SPHERE (H23) and NIRC2 (L’) datasets obtained in the best observing conditions for this study. I will then compare these images to predictions from hydro-dynamical simulations testing the hypotheses of a single (internal) eccentric companion, and two giant (internal+external) planets on circular orbits, respectively, and will discuss the likelihood of each scenario based on the similarity to our new images.
Quantifying the impact of stellar activity on transmission spectroscopy for F,G and K type host-stars
Authors: Chakraborty Hritam , Lendl Monika
Published: September 2022

Transmission spectroscopy remains one of the most powerful tools to infer the atmospheric properties of planets transiting a host star. This technique has resulted in robust detections of different chemical species like Na, K, TiO, H2O, CH4, etc on planets hosted by stars of different spectral types. However, the technique is prone to making errors in the case of planets orbiting active stars. Inhomogeneities on the stellar photospheres in the form of cool(spots) and hot regions(faculae) can distort the measurement of transit depth of a planet as they are often based on the assumption that the planet is transiting a homogenous point source. The presence of spots create a rise in transit depth at lower wavelengths which can be misinterpreted as an atmospheric signal associated with Rayleigh scattering. Moreover, it can also affect the detection of atomic species like sodium and potassium in the visible regime. The impact is especially strong in case of planets orbiting cool stars of spectral types F, G, K and M. 

 

We will present a quantitative analysis of the contamination effect of spots on the measurement of transmission spectra in the visible regime between 3000-10000 A for F, G and K-type stars. To measure this, we developed a customisable tool to model the spotted stellar photospheres using a pixelation approach. This also allows for the inclusion of limb-darkening and rotational broadening effects. The models indicate that the deviation on measurement of transit depth can vary from few PPM’s for F-type stars to hundreds of PPM’s for K-type stars.   
Rocky worlds: What do a planet's orbital parameters tell us about its mantle state?
Authors: Adhiambo Vivian , Root Bart , Desert Jean-Michel
Published: September 2022

Rocky (exo)planets can be classified based on their mantle viscous state. The mantle viscosity influences the efficiency of convection and heat loss of the planet, altering the outgassing rate. Low viscous planets are hypothesized to have strong volcanic activity reshaping the surface and changing the atmosphere. This can be seen in other almost-similar rocky bodies such as Io, one of Jupiter’s Galilean moons, and would be expected of young rocky exoplanets. Whereas, the intermediate viscous planets have less vigorous resurfacing. They experience occasional complete mantle-overturn to slow-moving plate tectonics driven by mantle convection. As a result, their atmospheres vary little or smoothly across time. High viscous planets can be seen as inert, with little or no mantle convection. Moreover, hotspot volcanism might still occasionally contribute to outgassing, producing a less dominant atmosphere. Through this relationship, a planet’s atmosphere could reveal information about the evolution of a planet's interior and surface. However, we rely on primary observables to characterize (exo)planets. So, is there a correlation between a planet's orbital position and mantle viscosity? The answer to this question would aid in the characterization of rocky exoplanets, which is the focus of this work. 

 

To study the relationship between a planet’s mantle viscous state, interior composition, and structure. We use Perple-X to generate mineral physics properties, and Burnman to build a 1-dimensional depth profile of the planet. From this, 2-dimensional annulus compressible convection models are developed using ASPECT. And, exploring the stagnant lid, the episodic lid, and the tectonic convection regimes. We consider the anelastic liquid approximation (ALA), and the truncated anelastic liquid approximation (TALA) formulations. An isoviscous profile results in a hot mantle but can be used for first-order approximations of mantle dynamics without a crust. However, the presence of crust requires for temperature-dependent stratified viscosity profile for the deeper mantle to allow for the cooling of the mantle. The stratification structure of the mantle is determined by the temperature sensitivity of the mineral phases present in the depth profile of the mantle. The iron mass fraction of the planet, which is highly dependent on the orbital position dictates the thermal state of the given planet. Moreover, a high mass iron fraction in the mantle results in a highly viscous planet. Which cools much faster but with a higher average temperature in the earlier phases of evolution. And vice versa to a similar mantle state with less iron mass fraction in the mantle.
Technical aspects of extracting millions of asteroids from TESS: data processing and pipeline structures at the flow of 4 terabytes/month.
Authors: Pál András
Published: September 2022

The Transiting Exoplanet Survey Satellite (TESS) produces a series of large field-of-view images with a size of 96x24 degress using a cadence of 10 minutes. Even when these field-of-views do not cover directly the ecliptic, thousands of asteroids are available for good quality photometry on a monthly basis. In this poster, we display the structure of the multi-stage pipeline designed to extract precise and accurate photometry from asteroids in an effective manner. The corresponding technical aspects include but not limited to the layout of the backend storage system, staging storages, data product indexing, memory utilization, metadata handling, intermediate products for shift & stack and efficient object querying implementation via SQL. Outputs of these pipeline stages are employed many presentations of this conference as perts of the early second data release.
Synergies between low- and high-resolution spectroscopy of exoplanet atmospheres
Authors: Morello Giuseppe , Pallé Enric , Orell-Miquel Jaume , Masseron Thomas , Esparza-Borges Emma
Published: September 2022

The composition of several exoplanet atmospheres has been largely debated with contrasting results in the literature. Low- and high-resolution spectroscopy offer complementary views, although sometimes appear to be in sparkling contrast. We present a new approach to simultaneously model low- and high-resolution observation and apply this method to resolve known controversies in the literature. We show that the synergy between different techniques of observations is significantly more informative than the separate analyses. We recommend the joint analysis of low- and high-resolution exoplanet spectra to fully exploit the potential of upcoming space missions, such as JWST, Twinkle and Ariel.
Does the non-dipolar structure of Uranus’ magnetic field produce a relatively weak proton radiation belt?
Authors: Masters Adam
Published: September 2022

Since the Voyager 2 flyby in 1986 the radiation belts of Uranus have presented a problem for magnetospheric physicists. The proton radiation belt was measured to be far less intense than the electron radiation belt, below theoretical predictions. Here we propose this could be a persistent characteristic of the environment that is due to the relatively strong non-dipolar structure of the planetary magnetic field. We model the trajectories of test particles in Uranus’ dipole-plus-quadrupole magnetic field and find that the quadrupole component causes their gradient-curvature drift to take them across dipole “L-shells” as they bounce between hemispheres. This finite-gyroradius effect is greatest for 100-keV protons, promoting the drift of these particles into regions where they are lost through impact with the rings, impact with the atmosphere, or to the more distant magnetosphere and solar wind. We suggest this could explain the relatively weak proton radiation belt observed by Voyager 2.
A lower-than-expected saltation threshold at Martian pressure and below 
Authors: Claudin Philippe , Andreotti Bruno , Iversen Jens Jacob , Merrison Jonathan P , Rasmussen Keld Romer
Published: September 2022

Aeolian sediment transport has been seen to occur on Mars as well as other extraterrestrial environments, generating ripples and dunes as on Earth. The search for terrestrial analogues of planetary bedforms, as well as environmental simulation experiments able to reproduce their formation in planetary conditions, are powerful ways to question our understanding of geomorphological processes towards unusual parameter sets. Here, using sediment transport laboratory experiments performed in a closed-circuit wind tunnel placed in a vacuum chamber, which is operated at extremely low pressures, we show that Martian conditions belong to a previously unexplored saltation regime. The saltation transport wind speed is quantitatively predicted by the state-of-the art models up to a density ratio between grain and air of 4x105, but unexpectedly falls, above this cross-over point, to much lower values than expected. By contrast, impact ripples, whose emergence is continuously observed on the granular bed over the whole pressure range investigated, display characteristic wavelength and propagation velocity essentially independent of the pressure. Testing these findings against existing models suggests that sediment transport at low Reynolds number but high grain to fluid density ratio may be dominated by collective effects associated with grain inertia in the granular collisional layer.

Ref: B. Andreotti, P. Claudin, J.J. Iversen, J.P. Merrison and K.R. Rasmussen, Proc. Natl. Acad. Sci. USA 118, e2012386118 (2021).
Constraining the stability and habitability of circumbinary planets
Authors: MacDonald Mariah , Pedowitz Michael
Published: September 2022

Although most stars exist in binary and multi systems, very few circumbinary planets (CBP) have been identified and studied. Observational biases contribute significantly to this paucity, as the orbital regions close to binaries are often unstable due to overlapping secular resonances. As we continue to improve our data reduction and analysis techniques, we can start to detect more planets farther from their stars and will therefore detect more CBPs. Through thousands of N-body simulations, we constrain the stability regions of an injected terrestrial planet around low-mass binaries, integrating the systems for 1Gyr or until instability. We then explore the potential detection and habitability of such planets. Through the 1Gyr evolution of the system, we trace the top-of-atmosphere temperature of the simulated planets to constrain the fraction that could host liquid water on their surfaces. Then, using a simple energy-balance model, we study the evolution of the planets' surface temperatures to identify which could host regions of continuous surface water.
New Python package to find, confirm, and characterize mean motion resonances
Authors: MacDonald Mariah
Published: September 2022

The study of orbital resonances allows for the constraint of planetary properties of compact systems. Mean motion resonance occurs when two or more planets repeatedly exchange angular momentum and energy as they orbit their host star, since the planets will always conjunct at the same point in their orbits. We can predict a system's resonances by observing the orbital periods of the planets, as planets in or near mean motion resonance have period ratios that reduce to a ratio of small numbers. However, a period ratio near commensurability does not guarantee a resonance; we must study the system's dynamics and resonance angles to confirm resonance. Because resonances require in-depth study to confirm, and because two-body resonances require a measurement of the eccentricity vector which is quite challenging, very few resonant pairs or chains have been confirmed. We thus remain in the era of small number statistics, not yet able to perform large population synthesis or informatics studies. To address this problem, we build a python package to find, confirm, and analyze mean motion resonances, primarily through N-body simulations. We verify our package by recovering the known resonances of Kepler-80 and Kepler-223. We then demonstrate the package’s functionality and potential by confirming new resonances, characterizing the mass-eccentricity degeneracy of Kepler-80g, and exploring the likelihood of an exterior giant planet in Kepler-80 and Kepler-223. We also study the formation history of K2-138 and constrain the planets’ masses and orbital parameters.
Investigation of planetary systems of WASP, TrES, Qatar and Kepler projects by using transit photometry with O-C parameter tracking and TTV method application on Kyiv Comet Station
Authors: Nahurna Anastasiia , Solomakha Mykhailo , Lobodenko Mariia , Baransky Olexandr
Published: September 2022

We report the results of the investigation of five planetary systems TrES-3b, Kepler-17b, WASP-3b, Qatar-1b, and Qatar-2b. For the exoplanets TrES-3b, Kepler-17b, WASP-3b, and Qatar-1b, the obtained results of the center-transit time, depth and length of transit agree with the ephemeris data, while for two observations of the Qatar-2 system for the planet Qatar-2b there is a clear decreasing trend of the value of the O-C parameter.

Observations were carried out from 2 April 2021 to 14 February 2022 by using a 70-cm reflecting telescope AZT-8 on the Astronomical Observatory of Taras Shevchenko National University of Kyiv / Kyiv comet station (Kyiv, Ukraine). Photometric processing of the observation results was performed by using the Muniwin program. The obtained exoplanet transit brightness curves were published in ETD. The accuracy and quality of our observations on the ETD database scale ranged from 1 to 3.

Additionally, applying the method of time transit variation (TTV) to our and Exoplanet Transit Database (ETD) data, we found a possible gravitational effect on the orbit of the exoplanet Qatar-2b of another massive body. This suggests that the assumption of the existence of the planet Qatar-2c conjectured in Bryan et al. (2011) is true.
The rich chemistry of two warm-giant planets 
Authors: Guilluy Gloria , Carleo Ilaria , Giacobbe Paolo , Sozzetti Alessandro , Bonomo Aldo
Published: September 2022

High-resolution (HR) ground-based spectrographs have drastically improved the investigation of exoplanet atmospheres. In this scenario the near-infrared (0.9-2.45 μm) HR (R /sim 50000) spectrograph GIANO-B mounted at the Nasmyth-B focus of the Telescopio Nazionale Galileo (TNG) telescope is playing an important role.

With the simultaneous detection of six molecules in the atmosphere of the Hot-Jupiter HD 209458b, we have recently demonstrated (Giacobbe+2021) that exoplanetary atmospheres can show a chemical richness previously unknown -as only a few molecules had been previously detected in an exoplanetary atmosphere.  Thus, the question of whether the complexity of HD 209458b’s atmosphere is unique or other exo-atmospheres can also show such a rich molecular composition arises spontaneously.

Here we report on transmission spectroscopy observations of two warm-giant planets, namely WASP-69b, and WASP-80b, gathered within the GAPS large program aimed at detecting atomic and molecular species in exoplanet atmospheres and possibly constraining the planetary C/O ratio, which is thought to be linked to planet migration and formation mechanisms.

We present the simultaneous detection of multiple molecules in the atmosphere of each of the investigated exoplanets -thus unveiling chemical richness also in warm Jupiters for the first time- and interpret the results in terms of possible scenarios of atmospheric composition (C/O ratio, metallicity). 

The analysis presented here, together with Giacobbe+ 2021, opens a new frontier in the characterization of exoplanetary atmospheres, and additional surprising discoveries are expected with both ground-based HR spectrographs, such as CRIRES+, SPIRou, and NIRPS, and the low-resolution (LR) spectrographs on board the JWST telescope.
Untangling rock-inhabiting microorganisms and their biosignatures from the Mars-like area of Puna Plateau, Argentinian Andes
Authors: Aureli Lorenzo , Coleine Claudia
Published: September 2022

Observations of the geological setting of the Martian surface suggest traces of a cold and semi-arid era during the evolution of the planet, characterized by desertic and evaporitic environments. Despite their hostile conditions, these challenging environments host highly adapted and specialized extreme-tolerant and extremophilic microorganisms that evolved unique strategies to survive the harshest conditions on Earth. like those observed in terrestrial microorganisms inhabiting extreme localities. Here, one of the most common strategies of microbial life is endolithism, defined as the colonization of the pores and ﬁssures within rocks, where microorganisms are protected from external harsher conditions. Moreover, the endolithic communities from Mars terrestrial analogues represent excellent models to understand how putative microorganisms may be adapted to the Martian environments and how to detect their signatures. In this optic, the proposed study aims to characterize for the first time endolithic communities and their biosignatures from distinct Mars-relevant rock substrates (ignimbrite and evaporites) in the Laguna Verde Complex, a complex of high-altitude hypersaline lakes surrounded by a desertic and volcanic area, located in the Puna Plateau in the Argentinian Andes. During the sampling campaign, which was performed in the context of the Europlanet 2024 Transnational Access program, rock samples were collected inside and in the surrounding desert area to cover most of the different potential endolithic habitats of the site. Microbiome characterization through Illumina amplicon sequencing, untargeted metabolomic analyses and microscopy studies are currently being undertaken on the collected samples.
Interior-atmosphere modelling of JWST rocky planets
Authors: Acuna Aguirre Lorena , Deleuil Magali , Mousis Olivier
Published: September 2022

Low-mass exoplanets, including rocky planets, might present atmospheres that are massive enough to be detected by JWST in transmission or emission spectroscopy. The first assessment of the observability of their atmosphere is based on their density, which is determined by their bulk composition and irradiance conditions. Interior models can be used in synergy with atmospheric models to get a first estimate of the possible atmospheric properties, including their surface pressure and temperature. In this work, we present a self-consistent interior-atmosphere model that retrieves the planetary internal composition, and generates spectra simultaneously. This allows us to assess the observability and predict spectra based on planetary mass, radius, and optionally, stellar abundances. We apply this model to derive the expected output with JWST for TRAPPIST-1 c and 55 Cnc e, which are two rocky planets proposed for observation that are suspected to have high-molecular weight atmospheres.

Figure 1: internal layers of our interior structure model. In the interior structure model for highly-irradiated planets, the ice VII and liquid water layers are substituted by a supercritical water layer.
From TESS single transits to well-characterized warm Jupiters
Authors: Ulmer-Moll Solène , Lendl Monika , Gill Sam , Villanueva Steven , Hobson Melissa , Mordasini Christoph , Bouchy François
Published: September 2022

Warm Jupiters provide a unique opportunity to better understand the formation and evolution of planetary systems. Their atmospheric properties remain largely unaltered by the impact of the host star, and their orbital arrangement reflects a different, and less extreme, migrational history compared to close-in objects. Warm Jupiters are known to cover a wide range of eccentricities but it is unclear which are the dominant formation pathways to explain this observation. Increasing the sample of long-period exoplanets with known radii is thus crucial. In this talk, I report the results of a survey set out to find transiting giants with orbital periods between 20 and 200 days. We selected 50 stars which show a single transit in one TESS sector (27 day baseline) and followed them with ground-based photometric and radial velocity facilities (e.g. NGTS, HARPS). After one year of observations, we report the detection and characterization of ten new transiting warm Jupiters, increasing by 50% the number of known warm Jupiters with precise masses and radii. We infer the metal enrichment of the newly discovered warm Jupiters and explore their influence on the mass-metallicity correlation of giant planets. The growing sample of warm Jupiters allows us to interpret these systems in terms of planet formation models. Finally, these targets orbit bright stars and thus are ideal for follow-up studies of the planetary atmosphere and the system' spin-orbit alignment. This work is a stepping stone for PLATO, as identification and follow up of single transit events will be key in order to detect transiting Earth-sized planets in the habitable zone of Sun-like stars.
High Level Datasets for ASPERA-3 IMA on Mars Express
Authors: Holmström Mats , Ramstad Robin , Futaana Yoshifumi , Persson Moa , Nilsson Hans , Barabash Stas
Published: September 2022

ESA's Mars Express (MEX) spacecraft has operated in Mars orbit since 2003. On-board MEX, the ASPERA-3 (Analyser of Space Plasma and EneRgetic Atoms) instrument is providing a unique dataset of the space plasma near Mars for more than 18 years, covering a complete solar cycle, allowing long-term inverstigation of the interaction of Mars with the solar wind.
The large number of observations also enables unique statistical studies. Here we present two ASPERA-3 Ion Mass Analyzer (IMA) higher level data sets that will be available through the ESA's Planetary Science Archive (PSA): Solar wind ion moments and Ion differential flux.
Detecting molecules in Ariel Tier 1 transmission spectra
Authors: Bocchieri Andrea , Mugnai Lorenzo V. , Pascale Enzo , Changeat Quentin , Tinetti Giovanna
Published: September 2022

The Ariel Space Mission will observe a large and diverse sample of exoplanetary atmospheres in the 0.5 to 7.8-micron range of the electromagnetic spectrum. As part of the Ariel observing programme, a shallow Reconnaissance survey (Tier 1) will provide transiting and eclipse spectroscopy on about 1000 targets, with low spectral resolution but sufficient SNR to identify the signature of molecular species. The wealth of information provided by this survey will be the basis for promoting targets for re-observation to reach sufficient SNR at higher spectral resolution. 

At the same time, these low spectral resolution observations are not suitable for estimating molecular abundances with an appropriate confidence level. Therefore, it is paramount to develop special data analysis techniques to extract their information content. This work investigates using the abundance posteriors from spectral retrieval as an unbiased metric to assess the presence of a molecule up to a certain threshold. 

The experimental dataset comprises simulated Tier 1 transmission spectra for about 300 targets from the Ariel Mission Reference Sample produced using the Alfnoor software. We use the TauRex 3 retrieval framework to run spectral retrievals on each “observed” spectrum, and we compute the probability that the spectra bear a molecule by integrating the posteriors above a specified threshold of molecular concentration. 

We find that the retrieved probabilities correlate with the abundances in the forward models and that this method is statistically reliable and has considerable predictive power and diagnostic ability. The predictive power is not significantly affected by adding molecules in the fitted composition that are not present in the forward models, while omitting molecules should be discouraged as it can lead to biased results. 
The embedded giant protoplanets in HD 100546
Authors: Fedele Davide
Published: September 2022

Among all the detection of exoplanets, the esistence of giant planets on wide orbits (r > 100 au) is of major importance to test the planet formation mechanism. At such distance from the star, grain growth is inhibited primarily by the low dust density. Gravitational instability might be at work in (some) disks. And yet, according to the measurements of the total gas mass, disks do not appear to be gravitationally unstables. The occurence of such 'cold Jupiters' remains a puzzle. Interestingly, the recent ALMA high angular resolution campaigns do show the presence of dust gaps and rings in protoplanetary disks on wide orbits, on spatial scales similar to those of cold Jupiters. In this regard, HD 100546 is a remarkable system.  

The protoplanetary system HD 100546: HD 100546 is a 2.5 solar mass star surrounded by a large disk extending out to nearly 500 au. The disk show spiral arms at different spatial scales, an inner dust cavity of nearly 28 au radius, a wide dust gap between nearly 50 and 150 au and a faint and eccentric outer ring centered at 200 au. Figure 1 shows the distribution of the millimeter continuum as seen by ALMA. The peculiar disk structures can be explained with the presence of two giant protoplanets (orbiting at at nearly 15 au and 100 au) interacting with the surrounding gas and dust. Notably, HD 100546 is one of the only disk in which cold water emission has been detected. I will present some recent ALMA results along with hydrodynamical simulations and a new analysis of the water distribution in the disk.
The Ariel Machine Learning Data Challenge
Authors: Waldmann Ingo
Published: September 2022

The use of machine and deep learning is prevalent in many fields of science and industry and is now becoming more widespread in extrasolar planet and solar system sciences. Deep learning holds many potential advantages when it comes to modelling highly non-linear data, as well as speed improvements when compared to traditional analysis and modelling techniques.

One such problem is the identification and de-trending of stellar and systematic instrument noise in exoplanet lightcurves and in particular time-resolved spectroscopy of exoplanet atmospheres.

As part of the ESA Ariel Space mission and the European Conference on Machine Learning (ECML-PKDD), we have organised two very successful machine learning challenges in 2019 and 2021 (https://www.ariel-datachallenge.space).  The aim was to provide new solutions to traditionally intractable problems and to foster closer collaboration between the exoplanet and machine learning communities. Often interdisciplinary approaches to long-standing problems are thwarted by jargon and a lack of familiarity. Data challenges are an excellent way to break down existing barriers and establish new links and collaborations.

The top-ranked approaches range from deep-learning to gradient boosted extreme learning machines. In this presentation, I will discuss their pros and cons of solving the set challenge and show how new ideas generated by the data challenges can achieve real progress in the field.
Connecting Stellar Abundance with Element Volatility & Rocky Planet Composition
Authors: Timmermann Anina , Reiners Ansgar , Pack Andreas , Shan Yutong
Published: September 2022

The formation and main element composition of rocky planets can be simulated as equilibrium condensation of the most common species in a protoplanetary disk with parameterized abundance patterns. We have developed an open access python code to perform condensation simulations based on a Gibbs free energy minimisation including thermochemical and stellar abundance databases. Our main objective was to provide a code that is easy to use, adapt, and expand. With our code, we simulated condensation for a representative selection of F, G and K stars. We analysed the influence of stellar abundance patterns and specific element ratios on the equilibrium chemistry in the protoplanetary disk. I will present our results about the connection between stellar elemental abundance patterns, volatility of elements, and planet composition. We found significant variations in condensation temperatures and planetary bulk compositions even for the conservative parameter range of 0.1 < C/O < 0.8, challenging previous assumptions regarding the general consistency of disk chemistry in low to medium C-systems. Our simulations show that the combined differences in various element ratios and overall metallicity of the system have an intricate effect on the condensation behaviour of solid phases. We systematise these effects in an effort to enable cursory estimations of planetary compositions.
A dual approach for the successful dissemination, use and improvement of educational resources in planetary science.
Authors: Pedreira Segade Ulysse , Heward Anita , Duras Federica
Published: September 2022

In recent years, the education and outreach teams in the Europlanet 2024 Research Infrastructure (RI) project, the Europlanet Society’s Outreach Working Group and the Europlanet Early Careers (EPEC) network have developed a number of resources to support teaching of science, technology, engineering, arts and mathematics (STEAM) subjects. We have created, tested, and published hands-on planetary science activities, ready-to-use astrobiology lessons, science education illustrations, etc, and we have also worked in collaboration with partner institutions and networks to run activities. In 2020 and 2021, we co-organised an educational programme linked to the virtual Europlanet Science Congress (EPSC) called ‘EPSC Goes Live for Schools’ in partnership with Lecturers Without Borders, Scientix and Frontiers.

We have now consolidated a database of all available resources and developed a plan for the successful and sustainable dissemination, use and improvement of these resources. This presentation will cover the strategy we have implemented.

On one hand, we will discuss the advantages and limitations of following a traditional top-down approach centred on using active communication channels in planetary science education. We have worked on creating a unified communication campaign that uses the diversity of topics tackled in order to guide users through our whole database of resources.

On the other hand, we will present the parallel bottom-up approach we have implemented, which focuses on building a supportive, inclusive and sustainable community around our resources. We will show the results of a consultation aimed at teachers and science communicators in order to understand their needs and identify gaps and bottlenecks in the planetary science education landscape at the European level. Based on this consultation, we are aiming to create a dynamic group of teachers, planetary scientists and science engagement practitioners who will work as users, content creators, peer-reviewers, translators of our activities, being a sustainable basis for the wide dissemination and access to our resources.

Finally, in order to learn from these approaches, we will present some preliminary results regarding the implementation of evaluation metrics throughout these steps.

Europlanet 2024 RI has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 871149.
PARSEC Alert System
Authors: Podlewska-Gaca Edyta , Langner Krzysztof , Wilawer Emil , Bartczak Przemysław , Garate Lopez Itziar , Hueso Ricardo , Kargl Gunter , Snodgrass Colin , Tautvaisiene Grazina
Published: September 2022

We present PlAnetaRy SciencE Collaboration tool (PARSEC), a service for coordinating the Solar System observations for observers and researchers. Parsec contains observational campaign coordination tool with alert system and email notifications. The service can be found at www.parsec-europlanet.eu.

In the framework of the Europlanet-2024-RI project we are  developping  a generalized Alert System for observations, which will notify and allow participating observatories to select appropriate targets across the diverse range of planetary science topics. This will provide both regular monitoring of targets and alerts for events  requiring time-critical and/or spatially distributed observations (e.g. stellar occultations by asteroids). The service will be based on the existing alert system software created to coordinate amateur observations of asteroids in support of the ESA Gaia mission (Gaia-GOSA, www.gaiagosa.eu, Santana-Ros et al., 2016).

We have chosen a toolset for the service development: PARSEC (PlAnetaRy SciencE Collaboration tool) which is a webapp created in Python, Flask and bootstrap frameworks with additional C++ code and postgresql database. The main features were programmed, thereby enabling request views on the main page, request filtering by observation date, target category, ownership, campaign view, and a notification system. The user can also establish preferences for notifications and follow requests/campaigns. In the „Requests” view there is the possibility of adding, editing, deleting, commenting the observational needs. Similarly, in „Campaigns” the user can start and coordinate observing campaigns of objects or events. In addition, observational alerts on topics related to planetary atmospheres are announced at the PVOL database (http://pvol2.ehu.eus/pvol2/) including in some cases detailed observation ephemeris and links to relevant campaigns around each alert. The service is currently under developmend, and testing by users is strongly recommended. The service can be found at www.parsec-europlanet.eu.

Santana-Ros T., Marciniak A., Bartczak P., 2016, “Gaia-GOSA: A Collaborative Service for Asteroid Observers”,MPBull, 43, 205

 
Ionospheric temperature variability above Jupiter’s Great Red Spot
Authors: Moore Luke , Stallard Tom , O'Donoghue James , Melin Henrik , Chowdhury M. Nahid , Johnson Rosie , Vogt Marissa , Schmidt Carl , Orton Glenn
Published: September 2022

In 2012, ground-based observations of the dominant molecular ion in gas giant ionospheres, H3+, found that Jupiter’s upper atmosphere was super-heated above its iconic Great Red Spot (GRS). Temperatures there reached 1600 K, hotter even than the auroral region. It was speculated that this GRS “hotspot” was the signature of coupling between Jupiter’s lower and upper atmosphere, perhaps associated with upward propagating acoustic or gravity waves originating from the Solar System’s most powerful storm system. Such an energy transfer could help explain why observed upper-atmospheric gas giant temperatures are all significantly warmer than simulations based solely on solar heating can explain, a discrepancy colloquially referred to as the “giant planet energy crisis”.

Here, based on ground-based observations from 2016-2019, we report on spatial and temporal variations of H3+ temperature surrounding the GRS. We find that, while upper-atmospheric temperatures are still elevated above the GRS, they vary in time and are significantly cooler than in 2012. In addition, there are consistent spatial variations, with H3+ temperature generally highest on the western and northern edges of the GRS. We place these results in context with recent work that implicates Jupiter’s aurorae as primary sources of upper-atmospheric heating, and comment on their implications for Jupiter’s energy crisis.
The Energy and Momentum Balance of Titan’s Stratospheric Polar Vortex as Simulated in a General Circulation Model
Authors: Lombardo Nicholas A , Lora Juan M
Published: September 2022

Titan’s stratospheric polar vortex is a prominent phenomenon of Titan’s global wind field, consisting of a westerly jet achieving speeds of nearly 200 m s-1 [1, 2].  The strong westerly winds have been hypothesized to serve as a mixing barrier to molecules transported to the high winter latitudes by Titan’s stratospheric meridional overturning circulation [2].  Similar to Earth’s stratospheric polar vortex, the vortex on Titan is primarily driven by diabatic cooling at high winter latitudes, resulting in a steep meridional temperature gradient and, via the thermal wind relation, a strong vertical wind shear [3].  While the existence and evolution of the vortex has been constrained for one half of a Titan year by observations from the Cassini spacecraft, a rigorous analysis of the potential mechanisms that give rise to the strong stratospheric jet has not yet been performed.

Here, using simulations from the Titan Atmospheric Model [4], which has recently been updated to better simulate Titan’s stratosphere [5], we study the temporal evolution of processes proposed to be responsible for the evolution of Titan’s stratospheric polar vortex, including: solar shortwave heating (largely controlled by the presence of stratospheric aerosols), adiabatic heating from the descending branch of the meridional overturning circulation, and molecular longwave cooling [3].

References

[1] Sharkey, J. et al, (2021) Icar 354, 114030

[2] Schultis, J., et al., (2022) PSJ 3, 73

[3] Teanby, N. A., et al, (2017), Nat Comm 8, 1586

[4] Lora, J. M., et al., (2015), Icar 250, 516 – 528

[5] Lombardo, N. A., et al., (in review), Icar
The NIR chemical composition of C/2021 A1(Leonard) at perihelion from CRIRES+ at the VLT
Authors: Vander Donckt Mathieu , Lippi Manuela , Faggi Sara , Jehin Emmanuel
Published: September 2022

We will present our observations of the bright comet C/2021 A1 (Leonard) with the newly upgraded CRIRES+ high resolution IR spectrometer mounted on the ESO VLT in Paranal, Chile. C/2021 A1 is a long period comet that reached perihelion on January 3, 2022, at 0.62 AU from the Sun. It is one of the brightest comet of recent years, reaching a visual magnitude of 3 close to perihelion (Seiichi Yoshida's webpage).

Originating from the cold Oort Cloud were it spent most of its dynamical lifetime, C/2021 A1 has presumably experienced little transformation or activity, keeping a pristine memory of the chemistry of the protoplanetary disk at the place where it formed. The sublimation of the nucleus volatile ices during its close approach to the Sun was an unique opportunity to have a glimpse at C/2021 A1 composition through the fluorescence of the species in its coma. We observed the comet with CRIRES+ for three nights close to its perihelion at 0.62 AU between December 28, 2021, and January 3, 2022, and derived the production rates of several parent volatiles including H2O, CH4, C2H6, H2CO and CH3OH. During the period of observation, the proximity to the Sun triggered a series of outbursts in C/2021 A1 (Jehin et al, 2022), enhancing the release of material in the coma and ultimately leading to the disintegration of the comet. The observations were made nodding on sky to subtract telluric features in the spectra, and the spectra were later corrected for atmospheric absorption (dominant in the NIR region) and wavelength calibrated by an atmospheric transmittance model computed with the ESO MOLECFIT software (Smette 2015). A flux reference star was also observed to calibrate the target's flux. The chemical composition of the comet will be compared to other comets from the same and other dynamical groups. The ongoing effort to build a chemical taxonomy of comets (A’Hearn et al., 1995; Dello Russo et al., 2016; Lippi et al., 2021) and compare it to the established dynamical classification underlies the need to better constrain the chemical composition of an increasing number individual comets. 

The high resolution IR spectrometer CRIRES+ is an upgrade of the CRIRES spectrometer into a cross-dispersed spectrograph, increasing the simultaneously covered wavelength by a factor 10 (Dorn et al, 2020). It has been available at the VLT since October 2021, offering a resolving power up to 100000 with a 0.2'' slit between 1 and 5 µm. This first observation of a comet with CRIRES+ will also serve to demonstrate its capabilities to target such objects in the IR.
Mentorship opportunities
Authors: Stonkute Edita
Published: September 2022

The planetary sciences and related fields are built on the foundation of sharing knowledge and making it accessible to all. In August 2020, Europlanet launched the Mentorship platform with the aim to support early career researchers. The platform is built to help early career scientists to develop expertise, ask questions and discuss career plans with the support of more established members of the planetary community. The success of the mentorship programme highlights the need for this programme and the potential role it can play in developing the individuals within our community who will advance planetary sciences over the coming years. On behalf of mentoring team, I will present the Europlanet mentorship platform and the current status of the programme. Europlanet 2024 RI has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 871149.