Stellar Surface Inhomogeneities as a Potential Source of the Atmospheric Signal Detected in the K2-18b Transmission Spectrum

Transmission spectroscopy of transiting exoplanets is a proven technique that can yield information on the composition and structure of a planet’s atmosphere. However, transmission spectra may be compromised by inhomogeneities in the stellar photosphere. The sub-Neptune-sized habitable zone planet K2-18b has water absorption detected in its atmosphere using data from the Hubble Space Telescope (HST). Herein, we examine whether the reported planetary atmospheric signal seen from HST transmission spectroscopy of K2-18b could instead be induced by time-varying starspots. We built a time-variable spectral model of K2-18 that is designed to match the variability amplitude seen in K2 photometric data, and we used this model to simulate 1000 HST data sets that follow the K2-18b observation strategy. More than 1% of these provide a better fit to the data than the best-fitting exoplanet atmosphere model. After resampling our simulations to generate synthetic HST observations, we find that 40% of random draws would produce an atmospheric detection at a level at least as significant as that seen in the actual HST data of K2-18b. This work illustrates that the inferred detection of an atmosphere on K2-18b may alternatively be explained by stellar spectral contamination due to the inhomogeneous photosphere of K2-18. We do not rule out a detection of water in the planet’s atmosphere, but we provide a plausible alternative that should be considered and conclude that more observations are needed to fully rule out stellar contamination.

MMX geodesy investigations: science requirements and observation strategy

In order to investigate the origin of Phobos and Deimos, the Japanese Martian Moons eXploration (MMX) mission is scheduled for launch in 2024. MMX will make comprehensive remote-sensing measurements of both moons and return regolith samples from Phobos to Earth. Geodetic measurements of gravity, shape, and rotation parameter of a body provides constraints on its internal structure reflecting its origin and evolution. Moments of inertia are important parameters to constrain the internal mass distribution, but they have not been well determined for the Martian moons yet. We discuss the mission requirements related to the moments of inertia to detect a potential heterogeneity of the mass distribution inside Phobos. We introduce mission instruments and operational strategies to meet the mission requirements. We present a preliminary imaging strategy from a quasi-satellite orbit for a base shape model that is expected to be created at the early stage of the mission. Geodetic products including ephemeris, gravity field, rotation parameter of Phobos, and spacecraft orbit are of importance not only for the geodetic study, but also for interpreting data from various mission instruments and selecting possible landing sites. Graphical Abstract

Myelodysplastic syndromes (MDS)

MDS in children is a rare group of hematopoietic stem cell clonal disorder. Allogeneic HSCT is the only curative treatment. HLA typing and the search for a compatible donor must be carried out upon diagnosis, for all patients. However, patients with refractory cytopenia of childhood without an unfavorable karyotype can keep the disease stable for a long time. Thus, in the absence of transfusion dependence or severe neutropenia, a careful observation strategy without treatment is recommended. The treatment of children diagnosed with MDS with excess blasts remains a major challenge. Allogeneic HSCT is the only curative treatment, although the data published in the literature generally include a small number of patients, heterogeneously transplanted. For children with MDS secondary to therapy, despite HSCT, the evolution is generally unfavorable.

FROM CONFLICT TO ALTERNATIVE SOLUTION: A CASE STUDY OF LOCAL INHABITANTS’ RESISTANCE TO TIN MINING IN SELINDUNG VILLAGE, BANGKA BARAT

The sea and the cost with the abundant resources frequently become the competition among the groups of interest. The competition is close to the conflict and ends up with the physical and verbal violence. Selindung village located in the coast area of Muntok, West Bangka is the area of the abundant resources, marine biota, and tin commodity. The contradiction of the economic interest causes the emerge of longer conflict. This study aims to map these conflicts and offers to the best alternative to cope with. This study is a qualitative research with the interview and observation strategy as the data collection. The result of the conflict mapping shows that the conflicted area shows the social tension. The pro and anti tin mining groups clash each other with the company interest, the local government, and the impact of the local people’s occupation interfere that causes a conflict. The conflict itself has experienced up and down however the various tin mining moduses stand still. The conflicts that have been mapped are the competition of resource access, the social jealousy, the policy of the maritime politics that does not accommodate the fishermen’ interest, as well as the issue of identity. There are four alternatives to get over these conflicts by referring to Galtung’s perspective namely supporting the role of government to be more accommodating and communicative to the majority interest, ensuring no extending licence of a large scale mining in the future, mediating by having two neutral parties, and finding new economic alternative to the local people who have already been depended on the mining activity.

A predictive model for the ichnological suitability of the Jezero crater, Mars: searching for fossilized traces of life-substrate interactions in the 2020 Rover Mission Landing Site

Ichnofossils, the fossilized products of life-substrate interactions, are among the most abundant biosignatures on Earth and therefore they may provide scientific evidence of potential life that may have existed on Mars. Ichnofossils offer unique advantages in the search for extraterrestrial life, including the fact that they are resilient to processes that obliterate other evidence for past life, such as body fossils, as well as chemical and isotopic biosignatures. The goal of this paper is evaluating the suitability of the Mars 2020 Landing Site for ichnofossils. To this goal, we apply palaeontological predictive modelling, a technique used to forecast the location of fossil sites in uninvestigated areas on Earth. Accordingly, a geographic information system (GIS) of the landing site is developed. Each layer of the GIS maps the suitability for one or more ichnofossil types (bioturbation, bioerosion, biostratification structures) based on an assessment of a single attribute (suitability factor) of the Martian environment. Suitability criteria have been selected among the environmental attributes that control ichnofossil abundance and preservation in 18 reference sites on Earth. The goal of this research is delivered through three predictive maps showing which areas of the Mars 2020 Landing Site are more likely to preserve potential ichnofossils. On the basis of these maps, an ichnological strategy for the Perseverance rover is identified, indicating (1) 10 sites on Mars with high suitability for bioturbation, bioerosion and biostratification ichnofossils, (2) the ichnofossil types, if any, that are more likely to be present at each site, (3) the most efficient observation strategy for detecting eventual ichnofossils. The predictive maps and the ichnological strategy can be easily integrated in the existing plans for the exploration of the Jezero crater, realizing benefits in life-search efficiency and cost-reduction.

Transitivity Shift in the Translated Official Website of Indonesian Ministry of Health

The objectives of this research are to depict the shift of transitivity that happen brought about by applying interpretation strategies in the translation on the site of Indonesian Ministry of Health. This research is Transitivity Shift In The Translated Official Website Of Indonesian Ministry Of Health. The samples of the research were clauses under the classification of experiential capacity that experience a shift in transitivity. The data were gathered by using the observation strategy. This strategy specifically selects articles that regulate Covid-19 and their translations in English. It has to carefully read every provision in the source language, then finding transitivity shifts by grouping it according to the experience capacity function. This research was analyzed by qualitative descriptive method and Systemic Functional Linguistic (SFL) approach. The findings showed that there are the transitivity shifts in the articles that published on 20th July and 11th September 2020. In conclusion, the transitivity shift in the analyzed articles, there are transitivity shifts on existential to verbal, material to relational, behavioral to material, verbal to relational and relational to existential. Nonetheless, there is no shift involving mental process in the two articles.

Influence of Indirect Solar Irradiance on Satellite Observation

With the development of Space Domain Awareness(SDA), satellites’ optical characteristics are becoming attention-grabbing. Sunlight was usually considered the only light source for the satellites. However, in the actual observation, researchers have found that earthshine and moonlight would increase errors of the observation results, which have greatly influence the estimation of the satellite’s state. In order to avoid this influence, we propose an observation strategy. Firstly, we propose an accurate earthshine model, which considers the earth’s volume and favors long-time continuous satellite observation. Then, we explore the earthshine and moonlight’s impact on satellite observation results and find that this impact varies with the satellite attributes. Furthermore, we Figure out the law of this impact and establish a connection between this law and observation geometry. Finally, a Period Contribution model is proposed to provide a corresponding observation strategy to avoid the influence of earthshine and moonlight.

The ASKAP Variables and Slow Transients (VAST) Pilot Survey

The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $\sim\!5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of $\sim\!162$ h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of $0.24\ \mathrm{mJy\ beam}^{-1}$ and angular resolution of $12-20$ arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.