Sky Project Research Articles

The Figurative System in the Works During the Russian-Ukrainian War: Nazhyvo (Live) and Mutilated Sky Projects

The article analyzes changes of the figurative system in works on military subjects, created in the period from the end of February 2022 to the middle of 2023, focusing on Nazhyvo (Live) and Mutilated Sky projects. The first exhibition of the Nazhyvo project featured works which declared their authors’ rootedness in the cultural layers of their homeland; the second exhibition focused on the theme of human interaction with the universe in times of war; the third exhibition showed the authors’ interest in mythology, which demonstrates a deeper level of artistic comprehension of Ukraine’s modern history. The author highlights that when changing the figurative system due to the expansion of topics and the depth of comprehension of dramatic events, the participants of the Nazhyvo project retain constant motifs in their works, such as archetypal images. In their artistic practices, the participants of the Mutilated Sky project realize the results of comprehending their own identity as a solid foundation in times of great suffering through the expression of rootedness in their family, community, and, more broadly, their native land. The rootedness expressed by the young artists in their own way confirms the tendency manifested in the works of Ukrainian artists during wartime. Thus, for the participants of the Nazhyvo and Mutilated Sky projects, it is important to mark identity in their artistic practices by conveying a connection with their ancestry as a family and their ancestry in the sense of their native land, as well as by placing the events of the Russian-Ukrainian war in a broader historical and cultural context. The effective realization of creative aspirations is facilitated by the development of a figurative system characterized by expansion in the development of sustainable motifs

HORuS transmission spectroscopy and revised planetary parameters of KELT-7 b

ABSTRACT We report on the high-resolution spectroscopic observations of two planetary transits of the hot Jupiter KELT-7b (Mp = 1.28 ± 0.17MJup, Teq = 2028 K) observed with the High Optical Resolution Spectrograph (HORuS) mounted on the 10.4-m Gran Telescopio Canarias (GTC). A new set of stellar parameters are obtained for the rapidly rotating parent star from the analysis of the spectra. Using the newly derived stellar mass and radius, and the planetary transit data of the Transiting Exoplanet Survey Satellite (TESS) together with the HORuS velocities and the photometric and spectroscopic data available in the literature, we update and improve the ephemeris of KELT-7b. Our results indicate that KELT-7 has an angle λ = −10.55 ± 0.27 deg between the sky projections of the star’s spin axis and the planet’s orbital axis. By combining this angle and our newly derived stellar rotation period of 1.38 ± 0.05 d, we obtained a 3D obliquity ψ = 12.4 ± 11.7 deg (or 167.6 deg), thus reinforcing that KELT-7 is a well-aligned planetary system. We search for the presence of Hα, Li i, Na i, Mg i, and Ca ii features in the transmission spectrum of KELT-7b but we are only able to determine upper limits of 0.08–1.4 per cent on their presence after accounting for the contribution of the stellar variability to the extracted planetary spectrum. We also discuss the impact of stellar variability on the planetary data. Our results reinforce the importance of monitoring the parent star when performing high-resolution transmission spectroscopy of the planetary atmosphere in the presence of stellar activity.

In Order to Know, We Must Imagine for Ourselves: How Artworks by Penny Siopis and Anton Kusters Re-present Traumatic Histories for Participatory, Open-Ended Re-imaginings

There are historical events that remain charged with trauma, thereby resisting the logic of causal progress conventionally ascribed to historical narratives. As obstacles to cohesive representations of history and national identities, these events remain ambiguous and problematic. Prompted by art historian and philosopher Georges Didi-Huberman’s proclamation “In order to know, we must imagine for ourselves” (Images in Spite of All. Chicago: Chicago University Press, 2012, p. 3), I argue that art, by not being intent on resolution or certitude, can offer opportunities to re-present, re-imagine, and re-think traumatic histories. In this article, I bring a selection of films by South African artist Penny Siopis, namely Obscure White Messenger (2010), The Master Is Drowning (2012), and Communion (2011), into conversation with the installation The Blue Skies Project (2018) by Belgian photographer Anton Kusters. I investigate how they engender affective encounters that probe the limits of the known. This is made possible by the artworks’ tangential approach to the events, activating the viewer’s imagination. The imagination facilitates a subjective, contingent, and indeterminate inquiry into the unknown, which the discipline of history often precludes. As viewers are tasked with the work of making meaning, I argue for the unique potential of art and the imagination as highly generative sources for engendering varying and differing expressions of knowledge that remain open-ended. Central to my argument is the way in which the artworks discussed grapple with the dialectics of the image, with the imbrication of the evidentiary and the imagination—knowing and un-knowing.

A Preponderance of Perpendicular Planets

Abstract Observing the Rossiter–McLaughlin effect during a planetary transit allows the determination of the angle λ between the sky projections of the star’s spin axis and the planet’s orbital axis. Such observations have revealed a large population of well-aligned systems and a smaller population of misaligned systems, with values of λ ranging up to 180°. For a subset of 57 systems, we can now go beyond the sky projection and determine the 3D obliquity ψ by combining the Rossiter–McLaughlin data with constraints on the line-of-sight inclination of the spin axis. Here we show that the misaligned systems do not span the full range of obliquities; they show a preference for nearly perpendicular orbits (ψ = 80°–125°) that seems unlikely to be a statistical fluke. If confirmed by further observations, this pile-up of polar orbits is a clue about the unknown processes of obliquity excitation and evolution.

An Ultradeep Multiband VLA Survey of the Faint Radio Sky (COSMOS-XS): Source Catalog and Number Counts

Abstract We present ultradeep, matched-resolution Karl G. Jansky Very Large Array observations at 10 and 3 GHz in the COSMOS field: the COSMOS-XS survey. The final 10 and 3 GHz images cover ∼16 and and reach median rms values at the phase center of 0.41 and 0.53 μJy beam−1, respectively. Both images have an angular resolution of ∼20. To account for the spectral shape and resolution variations across the broad bands, we image all data with a multiscale, multifrequency synthesis algorithm. We present source catalogs for the 10 and 3 GHz image with 91 and 1498 sources, respectively, above a peak brightness threshold of 5σ. We present source counts with completeness corrections included that are computed via Monte Carlo simulations. Our corrected counts at 3 GHz are consistent within the uncertainties with other results at 3 and 1.4 GHz but extend to fainter flux densities than previous direct detections. The 3 GHz number counts exceed the counts predicted by the semiempirical simulations developed in the framework of the SKA Simulated Skies project, consistent with previous P(D) analyses. Our source counts suggest a steeper luminosity function evolution for faint star-forming sources. The semiempirical Tiered Radio Extragalactic Continuum Simulation predicts this steeper evolution and is in better agreement with our results at 10 and 3 GHz within the expected variations from cosmic variance. In summary, the multiband, matched-resolution COSMOS-XS survey in the COSMOS field provides a high-resolution view of the ultrafaint radio sky that can help guide next-generation radio facilities.

Advanced Airspace Management Process

In order to increase efficiency and reduce delays, an improved airspace management process must be implemented leading to optimal route planning, better utilization of available airspace and increased performance targets in service delivery - through the establishment functional blocks of airspace (FABs). The Single European Sky (SES) project supports the establishment of the FAB through greater optimization and better performance, strengthening the ATM network through the introduction of the main objectives of the regulatory package, redesigning the European airspace in order to establish new air traffic flows; creating an increase in additional capacity, all with the aim of increasing the efficiency of the ATM system.

Dozens of virtual impactor orbits eliminated by the EURONEAR VIMP DECam data mining project

Context. Massive data mining of image archives observed with large etendue facilities represents a great opportunity for orbital amelioration of poorly known virtual impactor asteroids (VIs). There are more than 1000 VIs known today; most of them have very short observed arcs and many are considered lost as they became extremely faint soon after discovery. Aims. We aim to improve the orbits of VIs and eliminate their status by data mining the existing image archives. Methods. Within the European Near Earth Asteroids Research (EURONEAR) project, we developed the Virtual Impactor search using Mega-Precovery (VIMP) software, which is endowed with a very effective (fast and accurate) algorithm to predict apparitions of candidate pairs for subsequent guided human search. Considering a simple geometric model, the VIMP algorithm searches for any possible intersection in space and time between the positional uncertainty of any VI and the bounding sky projection of any image archive. Results. We applied VIMP to mine the data of 451,914 Blanco/DECam images observed between 12 September 2012 and 11 July 2019, identifying 212 VIs that possibly fall into 1286 candidate images leading to either precovery or recovery events. Following a careful search of candidate images, we recovered and measured 54 VIs in 183 DECam images. About 4,000 impact orbits were eliminated from both lists, 27 VIs were removed from at least one list, while 14 objects were eliminated from both lists. The faintest detections were around V ∼ 24.0, while the majority fall between 21 < V < 23. The minimal orbital intersection distances remains constant for 67% detections, increasing for eight objects and decreasing for ten objects. Most eliminated VIs (70%) had short initial arcs of less than five days. Some unexpected photometric discovery has emerged regarding the rotation period of 2018 DB, based on the close inspection of longer trailed VIs and the measurement of their fluxes along the trails. Conclusions. Large etendue imaging archives represent great assets to search for serendipitous encounters of faint asteroids and VIs.

Limits on the Flux of Nuclearites and Other Heavy Compact Objects from the Pi of the Sky Project.

Many theories predict the existence of very heavy compact objects, that in terms of sizes would belong to the realms of nuclear or atomic physics, but in terms of masses could extend to the macroscopic world, reaching kilograms, tonnes, or more. If they exist, it is likely that they reach our planet with high speeds and cross the atmosphere. Because of their high mass-to-size ratio and huge energy, in many cases, they would leave behind a trail in the form of sound and seismic waves, etches, or light in transparent media. Here we show results of a search for such objects in visual photographs of the sky taken by the "Pi of the Sky" experiment, illustrated with the most stringent limits on the isotropic flux of incoming so-called nuclearites, spanning between 5.4×10^{-20} and 2.2×10^{-21} cm^{-2} s^{-1} sr^{-1} for masses between 100g and 100kg. In addition we establish a directional flux limit under an assumption of a static "sea" of nuclearites in the Galaxy, which spans between 1.5×10^{-18} and 2.1×10^{-19} cm^{-2} s^{-1} in the same mass range. The general nature of the limits presented should allow one to constrain many specific models predicting the existence of heavy compact objects and both particle physics and astrophysical processes leading to their creation, and their sources.

Discovery of a Supercluster Candidate at z ∼ 1.1

Abstract We report a promising candidate for a distant supercluster at z ∼ 1.1 in the Dark Energy Survey Science Verification data. We examine smoothed semi-3D galaxy density maps in various photo-z slices. Among several overdense regions, in this work we report the most significant one as having a 3σ overdensity at a redshift of ∼1.1, over a ∼160 Mpc scale, much larger than the regular cluster scale (several Mpc). The shape of the supercluster is not circular in the sky projection. Therefore, we regard the point of maximum overdensity as the center for quantitative measurements. Two different estimates suggest the mass of the supercluster to be , more than one order more massive than regular galaxy clusters. Except for protosuperclusters found with emission-line galaxies, this could be the most distant supercluster to date defined by regular galaxies. A spectroscopic confirmation would make this a very interesting object for cosmology. We discuss the possible implications of such a massive structure for ΛCDM cosmology.

High-resolution, 3D radiative transfer modelling

Context. Interstellar dust absorbs stellar light very efficiently, thus shaping the energy output of galaxies. Studying the impact of different stellar populations on the dust heating continues to be a challenge because it requires decoupling the relative geometry of stars and dust and also involves complex processes such as scattering and non-local dust heating. Aims. We aim to constrain the relative distribution of dust and stellar populations in the spiral galaxy M 81 and create a realistic model of the radiation field that adequately describes the observations. By investigating the dust-starlight interaction on local scales, we want to quantify the contribution of young and old stellar populations to the dust heating. We aim to standardise the setup and model selection of such inverse radiative transfer simulations so these can be used for comparable modelling of other nearby galaxies. Methods. We present a semi-automated radiative transfer modelling pipeline that implements necessary steps such as the geometric model construction and the normalisation of the components through an optimisation routine. We used the Monte Carlo radiative transfer code SKIRT to calculate a self-consistent, panchromatic model of the interstellar radiation field. By looking at different stellar populations independently, we were able to quantify to what extent different stellar age populations contribute to the heating of dust. Our method takes into account the effects of non-local heating. Results. We obtained a realistic 3D radiative transfer model of the face-on galaxy M 81. We find that only 50.2% of the dust heating can be attributed to young stellar populations (≲100 Myr). We confirm that there is a tight correlation between the specific star formation rate and the heating fraction by young stellar populations, both in sky projections and in 3D, which is also found for radiative transfer models of M 31 and M 51. Conclusions. We conclude that old stellar populations can be a major contributor to the heating of dust. In M 81, old stellar populations are the dominant heating agent in the central regions, contributing to half of the absorbed radiation. Regions of higher star formation do not correspond to the highest dust temperatures. On the contrary, it is the dominant bulge which is most efficient in heating the dust. The approach we present here can immediately be applied to other galaxies. It does contain a number of caveats, which we discuss in detail.

A Cautionary Tale of Urban Media Art: Media-Bait, Planned Censorship and Its Repercussions

How do curatorial initiatives in public spaces balance the critical pursuit of art and the professional ethics of the exhibition context? What are the pros and cons of conducting attention-grabbing guerrilla campaigns versus infiltrating politically sensitive public arenas with long-term initiatives? What happens when corporate sponsors of art become trapped in the battlefield of art-fueled media controversy? This article expands on such inquiries by analyzing the collision of two artistic urban interventions, Open Sky Project and the Countdown Machine campaign—a collision that took place within the delicate political context of Hong Kong in 2016.

AN ALTERNATIVE APPROACH TO THE FINGER OF GOD IN LARGE SCALE STRUCTURES

It is generally accepted that linear theory of growth of structure under gravity produces a squashed structure in the two-point correlation function (2PCF) along the line of sight (LoS). The observed radial spread out structure known as Finger of God (FoG) is attributed to non-linear effects. We argue that the squashed structure associated with the redshift-space (s−) linear theory 2PCF is obtained only when this function is displayed in real-space (r−), or when the mapping from r − to s−space is approximated. We solve for the mapping function s(r) that allows us to display thes −space 2PCF in a grid in s−space, by using plane of the sky projections of the r − and s − 2PCFs. Even in the simplest case of a linear Kaiser spectrum with a conservative power-law r−space 2PCF, a structure quite similar to the FoG is observed in the small scale region, while in the large scale the expected squashed structure is obtained. This structure depends on only three parameters.

Just Culture – Eleven Steps Implementation Methodology for organisations in civil aviation – “JC 11”

This article aims to help organisations in aviation to build a Just Culture (JC). Building a Just Culture is a difficult task, but there are small, local steps that you can take internally. JC 11 steps methodology is a guide which lays out several them. This article maps the evolution of the Just Culture in Europe and within the Single European Sky project. European Commission significantly supports the positive JC in the company as well as on the state level. Your organisation can actively work to change some of the practices of your organisation and maybe even within your country. The main goal of this change is to improve the reporting culture of safety occurrences. Working towards a Just Culture means trying to change some key practices, some essential rules, and perhaps some critical relationships between stakeholders, so that, eventually, a Just Culture may emerge. In this article, we bring you a potential solution, how and where to start with the implementation of different processes of the JC infrastructure. A solution is the practical approach with the list of steps which lead you to the successful JC implementation and maintenance. This methodology is based on years of experience in the JC area in aviation and on the well-recognised literature. The positive JC in your organization will support employees to report the safety related issues and to bring a satisfactory solution as well. When the organization improves safety environment and apply safety measures, this will help to support employees in a more efficient approach to their work. New EC regulations also brought new challenges for aviation stakeholders in Europe to ensure the improvement of safety for future reference periods. These ambitious performance goals, such as improving safety and increasing efficiency and performance, require a structured approach into the implementation of different aspects of aviation safety.

Towards the harmonisation of Just Culture across organisations: the London Luton Airport case

Organisations at an airport, including the airport authority, airlines, air traffic management, ground handling and other services, must all have a Just Culture policy and system in place, according to EC regulation 376/2014. This is to protect employees and also to promote reporting and learning from safety-related events or hazards. However, there may be differences in such policies and the ways in which they are enacted, including the openness of the culture, the investigation processes, and the degree of authentic support from senior and middle management. As part of the H2020-funded Future Safety Sky project, and in collaboration with London Luton Airport (LLA), a Just Culture Framework has been developed which acts as an over-arching Just Culture policy for all companies operating at the airport. This paper shows how this framework was developed and ratified, with input from a number of companies based at LTN.

The Lockman Hole Project: new constraints on the sub-mJy source counts from a wide-area 1.4 GHz mosaic

This paper is part of a series discussing the results obtained in the framework of a wide international collaboration - the Lockman Hole Project - aimed at improving the extensive multiband coverage available in the Lockman Hole region, through novel deep, wide-area, multifrequency (60, 150, 350 MHz, and 1.4 GHz) radio surveys. This multifrequency, multi-band information will be exploited to get a comprehensive view of star formation and active galactic nucleus activities in the high-redshift Universe from a radio perspective. In this paper, we present novel 1.4 GHz mosaic observations obtained with the Westerbork Synthesis Radio Telescope. With an area coverage of 6.6 deg2, this is the largest survey reaching an rms noise of 11 uJy/beam. In this paper, we present the source catalogue (~6000 sources with flux densities S>55 uJy (5sigma), and we discuss the 1.4 GHz source counts derived from it. Our source counts provide very robust statistics in the flux range 0.1<S<1 mJy, and are in excellent agreement with other robust determinations obtained at lower and higher flux densities. A clear excess is found with respect to the counts predicted by the semi-empirical radio sky simulations developed in the framework of the Square Kilometre Array Simulated Skies project. A preliminary analysis of the identified (and classified) sources suggests this excess is to be ascribed to star-forming galaxies, which seem to show a steeper evolution than predicted.

3D mapping of the neutral X-ray absorption in the local interstellar medium: the Gaia and XMM-Newton synergy

We present a three-dimensional map of the hydrogen density distribution in the Galactic interstellar medium. The hydrogen equivalent column densities were obtained from the Exploring the X-ray Transient and variable Sky project ({\sc EXTraS}) which provides equivalent $N_{\rm H}$ values from X-ray spectral fits of observations within the {\it XMM-Newton} Data Release. {\sc EXTraS} include multiple fits for each source, allowing an accurate determination of the equivalent column densities, which depends on the continuum modeling of the spectra. A cross-correlation between the {\sc EXTraS} catalogue and the first {\it Gaia} Data Release was performed in order to obtain accurate parallax and distance measurements. We use a Bayesian method explained in \citet{rez17} in order to predict the most probable distribution of the density at any arbitrary point, even for lines of sight along which there are no initial observation. The resulting map shows small-scale density structures which can not been modeled by using analytic density profiles. In this paper we present a proof of concept of the kind of science possible with the synergy of these catalogs. However, given the systematic uncertainties connected to the source identification and to the dependence of $N_{\rm H}$ on the spectral model, the present maps should be considered qualitatively at this point.

Universal Visible Sky Factor: A method for calculating the three-dimensional visible sky ratio

This paper developed a new methodology for evaluating the visible sky ratio of a vertical building surface. A visible sky ratio is based on a surface viewpoint and measured by projecting obstacles onto a virtual three-dimensional (3D) hemisphere. Typically, virtual sky projection methods use two-dimensional (2D) mapping to calculate the amount of view of the outside. A major concern with 2D mapping is loss of accuracy due to the distortions in geometry that occur during the projection process. To address this limitation, a new projection method has been developed, supported by a computational numeric model that calculates the actual projection area of obstacles onto a 3D hemisphere. The new method improves the accuracy of the visible sky ratio without distorting obstructions. This new method can handle more complex conditions such as the forms of surrounding buildings, as well as various layouts, orientations, and heights. This study examines the new method via existing calculation processes in order to determine its robustness and limitations. The proposed method compared positively to these other existing methods, especially in terms of vertical changes in the observation point.

Spirited Skies project: Silica Aerogel in Art and Design Applications

ABSTRACTThis comparative study on two interdisciplinary artistic practices aims to improve public perception of scientific research and to facilitate informed decision making regarding climate change and how it affects everyday life. It also hopes to break down (or bridge?) the isolated silos of Art and Science, by emphasizing the role of imagination as a tool of creation and innovation in the new economies of the 21st century. Notwithstanding the ephemeral appearance of the super-light nanomaterial silica aerogel used by Ioannis Michaloudis (Michalous) in his sculptures, the longevity of some of his art seems guaranteed: two works, Bottled Nymph and Noli Me Tangere have been selected to be rocketed to the moon as part of the MoonArk sculpture. The sculptures will be aboard a Space X Falcon 9 rocket launched in 2018 from Cape Kennedy in an Astrobotic Robotic Lunar Mission, and will remain on the moon, potentially, for billions of years. Spirited Skies is a project where we experience by touching other forms of longevity of the ephemeral silica aerogel. Filling double jacketed borosilicate glass vials with aerogel skies and clouds in a unique way, Michaloudis transforms every day’s life trivial objects into art. And whilst Michaloudis is seeding the heavens and landing his artwork onto the moon, a Masters student under his supervision, Matthew van Roden is waxing and waning back here on earth. Van Roden’s material of choice is wax, which he pushes through various artistic disciplines to extrapolate its flesh like qualities.

Mechanical Impedance Matching Using a Magnetic Linear Gear

As part of the Fp7 Clean Sky Project, a linear magnetic gear prototype, called Z-transmitter, for aerospace application was designed, built, and tested. It demonstrates a maximum force capacity of 4700 N at 25°C and 4500 N at 90°C. Force ratio between slow and fast stages remains constant and equal to the design value: 7.0. The behavior of the real Z-transmitter as a mechanical impedance matching device when any stiffness is attached to the fast stage including the limit cases of a blocked fast stage or a free to move fast stage is experimentally explored. Although the real Z-transmitter deviates from the ideal, frictionless and massless, device, it still provides an impedance matching effect large enough to potentially become an extremely useful technology for vibration control when combined with other elements such as dampers, springs, or active elements.

Spirited Skies Project: Silica Aerogel Domes for the Habitat of the Future

The hypothesis of this paper is the examination of dome constructions using the space technology nanomaterial silica aerogel as insulating material. Silica aerogels are nanomaterials with excellent thermal insulations properties because 99.98% of their volume can be pure air. Insulation’s origin is the Latin insula ‘island’, an “isolated land” we could say. Planet Earth is a “space island”, in other words an oasis enveloped by its atmosphere: a layer of gases named sky surrounds our planet and protects life from genetic damage by ultraviolet solar radiation. By imitating nature -and in order to protect themselves-humans create garments and architectures. The primary function for garments and architecture is to insulate and to protect the human body. Silica aerogels could be considered as the eco friendly “plastic” of the 21st century because they can find application in any field. As aerogels are phenomenal energy savers they could be the paradigmatic materials for designing the insulation for future sustainable space habitats. Aerogels represent one of the most promising materials for thermally insulating buildings of the future, since the material demonstrates high performance, exhibiting thermal conductivities of 10-20 mW/(mK) in insulated, commercial products not used in a vacuum. Aerogels, when manufactured, can exhibit varying degrees of opacity, including both translucency and transparency, thereby enabling a diverse variety of applications for insulation in buildings that might require access to daylight or exploit sunlight for energy. Silica aerogel is the material-epicentre of all of the author’s multidisciplinary research. During the interactive presentation we will propose the design of small glass domes entitled Spirited Skies and Heaven in a Glass where silica aerogel was poured into jacketed glass beakers and micro clouds were settled in between the glazing. We suggest that the artificial clouds set on the transparent or translucent shell of these future space domes may relieve astronauts of their nostalgia of Earth, our home planet. With the same intention we also propose for a future space mission to utilise water (or wine) glasses with blue and gold skyscapes in double walled glass utensils.