Earth Day Research Articles

Planetary Waves Drive Horizontal Variations in Trace Species in the Venus Deep Atmosphere

Abstract The deep atmosphere of Venus remains mysterious because of the planet’s high, optically thick cloud decks. While phenomena such as the observed decadal fluctuations in sulfur dioxide abundance above the clouds could shed light on conditions below, poor understanding of vertical and horizontal transport limits such an approach. Nightside spectral windows permit observation of trace gas species in the lower atmosphere, but incomplete understanding of the circulation makes the distribution of these species challenging to interpret. We performed two simulations with the Venus Planetary Climate Model including an age of air calculation to investigate tracer transport (a) between the surface and the stagnant lower haze layer and (b) between the cloud deck and the observable upper atmosphere. We find a timescale on the order of many decades for surface-to-lower haze layer transport and ∼1.4 yr from the lowest cloud deck to 101 km. The extreme slowness of transport from the surface to the clouds makes it unlikely that compositional variability at the surface could affect the upper atmosphere sulfur dioxide abundance on observed timescales. Planetary-scale Rossby waves with a zonal wavenumber of 1 in both hemispheres are found to circumnavigate the planet in the deep atmosphere in 36 Earth days. These waves are associated with gyres that collect tracers and areas of upwelling that transport them to higher altitudes, leading to significantly younger air at polar latitudes in the altitude range of 25–45 km. The existence of chemically enhanced traveling Rossby gyres could explain the observed deep atmosphere carbon monoxide variability.

Challenges in illumination analysis and design for Martian surface-level habitation

It is needless to say that travel to and settlement on Mars are associated with extreme levels of scientific and engineering issues. This will only be amplified with the long-term duration of the mission, not only due to scarcity of resources, but also as the psychological aspects of the dynamics among the crew increase drastically. It should be emphasized that this is a scientific crew, who have undergone high levels of confinement during space travel to Mars, O (102 Earth days), are living in semi-solitude and partial confinement conditions for durations of O (103 Earth days), and even at the nominal termination of the mission, foresee a high-risk and arduous travel time of O (102 Earth days) back to the Earth. The mental weight of the described mission with its slow pace and tardy episodes, puts the crew under severe psychological issues. Minimal and conservative design of spaces, lack of constant access to the exterior, and social solitude are among major factors contributing to the psychological well-being of the crew. Furthermore, the overall lower levels of natural light, accompanied by the minimum possible area of transparent facades, protecting the crew from harmful radiations and cold exterior, burden the mental conditions of the crew even more. Given the limited availability of data from the surface of Mars, study of the effects linked to the lighting and illumination design of the habitats is challenging. The current manuscript hopes to shed light on the illumination and lighting design and simulation procedure, required data, assumptions, and final results for the surface-level habitats on Mars.•Mars / Sub orbital configuration allows for limited natural lighting, however, upon site-specific analysis, it might be considerable as a base passive source.•Current simulation tools are design based on Earth-bound design requirements. These need to be re-oriented to match available planetary data.

3- and 6-degree-of-freedom analysis of the Magellan aerobraking experiment and planar aerobraking at Venus

The first non-Earth aerobraking experiment occurred in 1993 as part of the Magellan satellite's mission to Venus. Magellan reduced its orbit from elliptical to nearly circular over a span of 70 Earth days by leveraging the non-conservative force of aerodynamic drag to reduce its orbital energy via transiting the upper region of Venus' sensible atmosphere. First tested with the Hiten probe in the Earth-Moon system in 1991, the subsequent Magellan experiment helped prove the viability of aerobraking for planetary missions and paved the way for its implementation in Mars missions starting in the late 1990s and the 2014 Venus Express mission. This paper, for the first time in literature, investigates the Magellan aerobraking experiment from the perspective of both 3- and 6-degree-of-freedom analysis. Multiple atmospheric density models are considered, as well as J4 gravitational perturbations in order to understand the complexity and sensitivity of numerous aerobraking maneuvers in the thick Venusian atmosphere. Alternative satellites are also studied to ascertain their capability of maintaining the Magellan aerobraking flight profile. So as to examine a wide range of vehicle mass and drag reference area, the Hubble Space Telescope (HST) and Hiten satellites are modeled and their aerobraking performance analyzed for the hypothetical case of Venus orbital operations. When reconstructing the historical Magellan aerobraking maneuvers, 3DOF and 6DOF analysis yielded minimal trajectory deviation with the Magellan and Hiten models, while more significant deviation was experienced with the larger HST model. Both 3DOF and 6DOF analyses also reveal the sensitivity of the atmospheric density model and indicate a higher fidelity gravity model is necessary for Venusian aerobraking modeling, planning, and analysis.

Celebration of the Earth Day 2024 – A Report

Celebration of the Earth Day 2024 – A Report

Why We Must Stop Saying “Climate Apocalypse”: Symbols, Religious Social Memory, and Effective Climate Action

The apocalyptic framework has become a handy metaphor for climate change because this story, better than most others, is able to express the scope and severity of the transformation most scientists believe is coming to humanity’s planetary and social systems. Since the first Earth Day in 1970 (Bailey 2000) and increasingly in journalistic media, nongovernmental organization circles, scientific literature, academia, eco-activism, and youth culture, climate change is referred to in world-ending terms that are explicitly apocalyptic. Those who use the phrase “climate apocalypse” mean to spur serious confrontation with the facts of climate change, resulting in climate activism, whether in the form of climate change mitigation or shoring up societal resiliency. However, stories not only describe reality, they help shape reality, and “climate apocalypse” has the unintended effect of creating passivity, fear, paralysis, and naïve hope in its audience.

Silence: A Novel Co-Produced Experience To Build Community Awareness Of Biodiversity Loss

The current sounds of our world are under threat of disappearing. Undergraduate students and interdisciplinary university teams are at the forefront of generating collaborative research opportunities to create community awareness of biodiversity loss and conservation practices. Recent conservation research has focused on how local communities can begin to reverse the trends of biodiversity loss by using private residences and urban spaces. The inclusion of native plants in backyard gardens is an accessible way to promote ecological restoration. In this co-produced instructional exhibit, “Earth Day Celebration: Silence,” we introduce a novel experiential event that connects instructional design with community collaboration. The event was designed to explore the ways in which society can become engaged in the preservation and protection of biodiversity and our sonic world.

Every day is Earth Day: Indigenous Peoples and their knowledges for planetary health

Every day is Earth Day: Indigenous Peoples and their knowledges for planetary health

When the Past Teaches the Future: Earthquake and Tsunami Risk Reduction through Episodes of Situated Learning (ESL)

The past offers important lessons with regard to facing the future with greater awareness. In this context, school plays a key role in spreading knowledge of natural phenomena and in promoting behavior change. Together with researchers, teachers can be strong allies to build more resilient future citizens. The Istituto Nazionale di Geofisica e Vulcanologia (INGV) school training activities provide tools to prepare for the next earthquake and/or tsunami. Approximately 5000 students, from both middle schools (ISCED 2) and high schools (ISCED 3), were involved in active learning activities based on a flipped-up approach during specific online scientific events during the pandemic. Online lab activities were conducted during European Researchers’ Night (“Earthquakes: history teaches us the future: researchers for a day with experimentation in didactics for ESL”) and during both World Water Day 2021 and World Earth Day 2021 (“Tsunamis: history teaches us the future researchers for a day with experimentation in didactics for ESL”). These two Episodes of Situated Learning (ESL) experiences triggered students’ interest, favoring remote learning, developing life skills, and focusing on historical seismic studies of both past earthquakes and tsunamis.

A study of Jupiter's UV Great Dark Spot and tropopause to stratosphere winds in the high northern latitudes as seen by Cassini imaging

Images of Jupiter taken during the year 2000 Cassini flyby revealed the early stages and evolution of a high northern-latitude UV Great Dark Spot over a three-month period. They also provided a window on the circulation of Jupiter's polar stratosphere. Jupiter's rarely-detected UV Great Dark Spot (UVGDS) is unusual in several respects. It is an ephemeral feature, twice appearing as an oval with size and shape similar to Jupiter's Great Red Spot (GRS). Like the GRS, it is an anticyclonic feature. It is unlike the GRS in that: (1) A gas, and/or very small particles (radius < < 1 micro meter, of unknown composition but likely hydrocarbon) is responsible for its contrast with its surroundings; (2) It appears to be a shallow feature, confined to the stratosphere; (3) It evolves (moves in System III longitude, elongates and tilts) over a period of months; and (4) It may be produced by an auroral event as inferred by its proximity to the southern extent of Jupiter's main auroral oval. However, we did not identify a specific auroral trigger event. We measure the rotation rate for the UVGDS to have been ∼20° per Earth day. To investigate the dynamical regime of this feature, we applied an automated cloud feature tracking algorithm to Cassini Imaging Science Subsystem images of Jupiter's northern hemisphere (30°N – 80°N) in the near-IR continuum, methane band, and ultraviolet filters. From these images we were able to derive zonal wind profiles from the middle troposphere cloud tops to the lower stratosphere and track the evolution of the UV Great Dark Spot. Differences in mean zonal wind speed between the continuum and methane band filters indicate a weakening of jets with altitude as far north as 75°N latitude at the altitudes sampled by these filters. We also observe notable differences between the ultraviolet and the other two filters: (1) Winds are significantly weaker and mostly westward in the ultraviolet relative to lower altitudes at all latitudes equatorward of 60°N latitude; (2) Poleward of 60°N latitude, winds observed in the ultraviolet may be faster than those observed in the continuum and methane bands, though we are less confident in this result as Jupiter's haze morphology and the lack of small, discrete, unambiguous trackable features present unique challenges to obtaining reliable mean zonal winds in the ultraviolet at high latitudes.

Renewing Protest and Earth Day at School: Thinking with Recent Texts on Anticolonial Methods and Climate Change Education

Renewing Protest and Earth Day at School: Thinking with Recent Texts on Anticolonial Methods and Climate Change Education

The first biological experiment on lunar surface for Humankind: Device and results

The Bioregenerative Life Support System (BLSS) is an indispensable part of extraterrestrial bases as it can provide sufficient food, fresh air, recycle waste, and create a safe environment for humans. However, it is still uncertain how the natural environment of extraterrestrial bodies would affect the function of an artificial ecosystem like BLSS. The Chinese Chang'e 4 lunar lander carried a micro-ecosystem called Biological Experiment Payload (BEP), developed by Chongqing University, and conducted the first biological experiments for humans on the back of the Moon to assess the effects of low gravity, intense radiation, and light on the lunar surface to living things. The payload weighs 2.608 kg, with 198 mm in height and 173 mm in diameter, offering a total inside space of 0.82L, containing 0.42L of bio-activity space. Cotton seeds, Potato seeds, Arabidopsis seeds, Rape seeds, Fly eggs, Yeast, and 18 ml of water were placed in the BEP, which was kept at a constant atmospheric pressure. Through a light guide tube, sunlight from the lunar surface can enter the payload's interior, allowing plants to photosynthesize. One remarkable feature of BEP was the gap in radiation protection design.On January 3, 2019, BEP arrived on the back of the Moon and conducted an experiment lasting eight days, 22 h, and 45 min (Earth Day) during the first lunar day after landing. After 22 h of watering, the CCD camera captured cotton seed germination, compared to 53 h after watering in the ground synchronization experiment. The cotton seedling on the lunar surface showed a faster germination rate than the simultaneous experiments on the ground. Also, the morphology of the cotton on the Moon was changed, with its stem growing curved, developing a long part close to the substrate and a short upright portion while forming fat-flowing nodes close to the substrate. Finally, the leaves were also curled and did not unfold. The payload was dormant from 12 to 31 January 2019, with its interior remaining dark and temperatures reaching as low as −52 °C. After the lunar night, the leaves of the terrestrial synchronous experiment were completely blackened and in pieces, in contrast to the Seedling on the Moon, which was upright and green. This experiment demonstrated that plants could grow on the lunar surface even in intense radiation, low gravity (1/6 g), and prolonged intense light. It was also the first time that a biological experiment was carried out by humans on the Moon using sunlight from space to power photosynthesis.

‘Good Cause for Living’: Environmental Justice in Virginia Hamilton’s M. C. Higgins, the Great

This article offers an ecocritical reading of Virginia Hamilton’s celebrated novel M. C. Higgins, the Great (1974) to reposition it as a milestone of environmental writing for children. Arriving concurrently with the first Earth Day in the United States in 1970, the novel exposes the generational effects of environmental racism toward Black Americans in the steel industry and condemns the ongoing injustices of strip-mining in Appalachia. However, the novel remains neglected in the primarily white space of ecocriticism. Rereading it as a text for environmental justice recentres Hamilton’s contribution to environmental writing for children and prompts reflection amongst scholars about whose stories occupy which spaces in critical study.

Periodic Variation of Mesoscale Ultraviolet Contrast at the Cloud Top of Venus

AbstractImages of Venusian clouds taken at ultraviolet (UV) wavelengths frequently exhibit mesoscale cellular structures at low latitudes. To obtain clues regarding the origin of these structures, we studied the temporal variation of the mesoscale UV contrast using 283‐ and 365‐nm images taken by the ultraviolet imager (UVI) onboard the Akatsuki spacecraft. The 283‐nm channel is mostly affected by SO2 at the cloud top and the 365‐nm channel is mostly affected by an unknown absorber, though both absorbers are thought to influence both wavelengths. We defined the mesoscale as a spatial scale roughly below 1,000 km, where the effect of large‐scale streaky patterns is not significant according to the spatial spectra of 283‐nm images taken by UVI and 2.02‐μm images taken by the near‐infrared camera (IR2) onboard Akatsuki. We found that the temporal variation of the standard deviation of the mesoscale UV contrast is dominated by quasi‐periodic oscillations with amplitudes of 30%–50% relative to the mean value and periods of around 4–5 Earth days. Oscillations of the planetary‐scale UV contrast with similar periods were also observed, suggesting that the mesoscale structures are influenced by planetary‐scale waves. The mesoscale contrast tends to be enhanced when the background albedo decreases in the course of the propagation of planetary‐scale waves. This correlation suggests that the solar heating near the cloud top level feeds the mesoscale dynamics. An enhancement of the mesoscale contrast in the afternoon was seen at a wavelength of 365 nm.

ŽEMĖS DIENOS RENGINIAI: TVARUMO IDĖJOS IKIMOKYKLINUKAMS

As environmental issues become more relevant, more attention is paid to sustainability. Sweden's long-term experience shows that including sustainability topics in preschool education programs allows children to feel like they are masters of their planet, responsible for its future. The article shares the experience of how environmental issues were discussed in a group of four-year-old children during the month-long educational activities dedicated to Earth Day. With the help of the teacher, the children explained which human activities in nature are appropriate and which are not. They looked for evidence of such activities in the environment and shared their experiences. In Lithuanian, the spring months are named after birds. Children got to know rook, dove and cuckoo. They looked for signs of spring in the school yard. While performing a creative task, children shared their thoughts on how they can contribute to protecting the nature of the planet. In other activities, children learned about our planet, its continents and oceans. After planting vegetable and flower seeds, they watched how the plants grew and developed. The peppered "continents" allowed the children to imagine that our planet is green and beautiful when many animals breed on it. So we have to preserve it as green and we are all responsible for its future. By researching and performing practical activities, children improved initiative and perseverance, knowledge of the environment, research, and problem solving skills. Keywords: educational activities, problem solving skills, preschool education, education for sustainability

Maps of Solar Wind Plasma Precipitation onto Mercury’s Surface: A Geographical Perspective

Mercury is the closest planet to the Sun, possesses a weak intrinsic magnetic field, and has only a very tenuous atmosphere (exosphere). These three conditions result in a direct coupling between the plasma emitted from the Sun (namely, the solar wind) and Mercury’s surface. The planet’s magnetic field leads to a nontrivial pattern of plasma precipitation onto the surface that is expected to contribute to the alteration of the regolith over geological timescales. The goal of this work is to study the solar wind plasma precipitation onto the surface of Mercury from a geographical perspective, as opposed to the local time-of-day approach of previous precipitation modeling studies. We employ solar wind precipitation maps for protons and electrons from two fully kinetic numerical simulations of Mercury’s plasma environment. These maps are then integrated over two full Mercury orbits (176 Earth days). We found that the plasma precipitation pattern at the surface is most strongly affected by the upstream solar wind conditions, particularly the interplanetary magnetic field direction, and less by Mercury’s 3:2 spin–orbit resonance. We also found that Mercury’s magnetic field is able to shield the surface from roughly 90% of the incoming solar wind flux. At the surface, protons have a broad energy distribution from below 500 eV to more than 1.5 keV, while electrons are mostly found in the range 0.1–10 keV. These results will help to better constrain space weathering and exosphere source processes at Mercury, as well as interpret observations by the ongoing ESA/JAXA BepiColombo mission.

A Report on the Earth Day 2023 – Invest in Our Planet

A Report on the Earth Day 2023 – Invest in Our Planet

22. АПРИЛ – СВЕТОВЕН ДЕН НА ПЛАНЕТАТА ЗЕМЯ. НАШАТА ПЛАНЕТА, НАШ ДОМ

In this report, Ms. Baneva wants to give publicity to the problem of pollution of the planet Earth and the climate. This day has been celebrated since 1970 in the USA and Canada, and since 1990 has been declared international. In Bulgaria, this day has been celebrated since 1993, and aims to unite people around the idea of protecting the environment and crime. The fight against climate change must be persistent and decisive, but only the actions of people can show whether we will succeed. Climate change is one of the biggest problems in recent years and many global organizations are constantly discussing solutions to reduce this problem. All destruction in nature, targeted pollution and climate change lead to the destruction of the planet’s biodiversity. World Earth Day was held in the group for a full-day organization of the school day 2nd grade First Primary School. „Cyril and Methodius“, Gotse Delchev.

Moon Diver: Exploring a pit's exposed strata to understand lunar volcanism

Natural pits on the Moon expose deep cross-sections of the lunar maria, enabling direct investigation of the Moon's volcanic history and providing potential access to subsurface lava tubes. The Moon Diver mission concept seeks to explore the Mare Tranquillitatis pit, which exposes the largest wall of bedrock of the mare pits (∼65 m). The concept is enabled by two innovative capabilities: pinpoint landing near the pit and robotic access to its near-vertical wall with an instrument package to examine the elemental chemistry, mineralogy, and morphology of these bedrock layers. Pinpoint landing uses closed-loop guidance with terrain-relative navigation (TRN), which was advanced by Perseverance landing on Mars, to deliver the lander within a 100-m ellipse. The Axel robotic explorer, which remains tethered to the lander, would egress onto the lunar surface and traverse the relatively flat terrain to the pit's funnel entrance. The lander, which is the data link to Earth, also serves as an anchor and provides power and communication to the rover through its tether. The rover is a novel two-wheeled platform with a trailing boom and a spool that pays out the tether as the rover traverses toward the pit. The 300-m long tether is well margined for the rover to scale the pit wall. The rover carries a surface preparation tool and three additional instrument types: (a) three high-resolution cameras for acquiring context images of the near and far walls with the near-wall pair in a stereoscopic configuration, (b) an alpha-particle-X-ray spectrometer (APXS) for elemental composition, and (c) a multi-spectral microscopic imager (MMI) that uses controlled lighting for mineralogy. The surface-preparation tool removes dust and patina from the rock wall by grinding a small area. This tool, the MMI, and the APXS would be deployed from an instrument bay inside the wheel wells. The rover would independently point each instrument at the same target on the wall with millimeter repeatability. Landing shortly after sunrise, the surface mission timeline is just shy of a lunar daytime (14 Earth days). Beyond the primary mission, the rover would be capable of descending from the overhang and peering into the void that may open to a large cave or lava tube. Lunar pits provide an exciting new target for exploration using innovative robotic capabilities that have been tested with integrated science instruments at multiple terrestrial analogue sites including a pit with basaltic layers in Arizona.

Harmonic oscillations of circadian rhythms come out of the shadows

About 40 % of the liver transcriptome display a circadian expression. Recently, harmonic oscillations of the circadian rhythm and independent of the circadian clock have been identified. Transcripts oscillating with a 12h period are involved in fundamental and ubiquitous cellular mechanisms such as proteostasis, lipid metabolism or RNA metabolism. A 12h ultradian oscillator involving the UPR response regulator XBP1, the coactivator SRC-3 and the speckle protein SON has been uncovered. The XBP1 oscillator and the 12h ultradian transcriptome are highly conserved suggesting an early emergence that may date back to a time when the Earth's day was much shorter than 24h.

Seven Sisters: a mission to study fundamental plasma physical processes in the solar wind and a pathfinder to advance space weather prediction

This paper summarizes the Seven Sisters solar wind mission concept and the outstanding science questions motivating the mission science objectives. The Seven Sisters mission includes seven individual spacecraft designed to uncover fundamental physical processes in the solar wind and provides up to ≈ 2 days of advanced space weather warnings for 550 Earth days during the mission. The mission will collect critical measurements of the thermal and suprathermal plasma and magnetic fields, utilizing, for the first time, Venus–Sun Lagrange points. The multi-spacecraft configuration makes it possible to distinguish between spatial and temporal changes, define gradients, and quantify cross-scale transport in solar wind structures. Seven Sisters will determine the 3-D structure of the solar wind and its transient phenomena and their evolution in the inner heliosphere. Data from the Seven Sisters mission will allow the identification of physical processes and the quantification of the relative contribution of different mechanisms responsible for suprathermal particle energization in the solar wind.