The theoretical discoveries of the Sanal flow choking [V. R. Sanal Kumar et al., “Sanal flow choking: A paradigm shift in computational fluid dynamics code verification and diagnosing detonation and hemorrhage in real‐world fluid‐flow systems,” Global Challenges 4, 2000012 (2020)] and streamtube flow choking [V. R. Sanal Kumar et al., “Deflagration to detonation transition in chemical rockets with sudden expansion/divergence regions,” AIAA Paper No. 2020-3520, 2020] achieved significant contemplation in all branches of science and engineering for resolving various unanswered scientific questions brought onward from the beginning of this era [V. R. Sanal Kumar et al., “A closed-form analytical model for predicting 3D boundary layer displacement thickness for the validation of viscous flow solvers,” AIP Adv. 8, 025315 (2018)]. The applications of these flow choking phenomena are more significant in aerospace industries [V. R. Sanal Kumar et al., “Nanoscale flow choking and spaceflight effects on cardiovascular risk of astronauts—A new perspective,” AIAA Paper No. 2021-0357, 2021] and medical sciences [V. R. Sanal Kumar et al., “Lopsided blood-thinning drug increases the risk of internal flow choking leading to shock wave generation causing asymptomatic cardiovascular disease,” Global Challenges 2021, 2000076]. Herein, as an offshoot of the Sanal flow choking phenomena, the proof of the concept of boundary-layer-blockage (BLB) persuaded external-flow-choking (EFC) at aircraft-in-ground (AIG)-effect is presented. When the aircraft's ground clearance is relatively low, the evolving BLB factor from both planes (the bottom surface of the aircraft and the ground) creates a transient fluid-throat, leading to the Sanal flow choking and supersonic flow development in the duct flow region. In this physical situation, the pressure ratio (P_total/P_static) at the external flow choking region is exclusively a function of the specific heat ratio of the fluid. The EFC is more prone for the low wing aircraft flying in the near vicinity to the ground and/or sea with relatively high subsonic Mach number and low angle of attack. At this flying condition, the underside of the aircraft (fuselage and/or wing) and the ground creates the convergent-divergent duct flow effect leading to the EFC at the critical total-to-static pressure ratio. The accurate estimation of the BLB factor at the location of the EFC at AIG effect is presented in this manuscript as a universal yardstick for two-dimensional (2D) in silico simulation. For establishing the proof of the concept of external flow choking and supersonic flow development and shock wave generation, the 2D in silico results are presented for both stationary and moving airfoils in ground effect. In silico results show that the airfoil at stationary position exhibits relatively higher BLB factor and an immediate occurrence of the EFC than the same airfoil moving with the identical inflow Mach number and Reynolds number. We could establish herein that the moving vehicle simulation is inevitable for capturing actual flow physics and further precise examination of the BLB factor and the possibilities of the occurrence of the EFC for credible trajectory optimization of high-speed ground-effect vehicles.

Kessler’s Syndrome is a global phenomenon characterized by the presence of tens of millions of debris pieces of various sizes that disrupt satellite operations. This article delves into the potential outcomes of a Kessler’s Syndrome occurrence and its implications on satellite operations. The potential threats posed by this scenario are discussed, including the implications of minimal to no satellite function on human impacts, including crashes and minimized or disrupted functions in essential utility services, as these sectors heavily rely on satellites. In addition, we discuss how the loss of satellite communications could gradually or rapidly affect global affairs. As humans are a dominant force on Earth, their endangerment would reverberate throughout the ecological system, potentially leading to the demise of other species. It is crucial for policymakers and relevant stakeholders to recognize these implications and work towards safeguarding satellite communication to mitigate potential negative outcomes for humanity’s wellbeing and progress. The recycling of space debris emerges as a promising and long-term sustainable solution to the mitigation of space debris. By repurposing decommissioned satellites and debris into useful materials to support other space missions, this recycling strategy presents a win-win scenario, promoting environmental sustainability and resource efficiency in space exploration.

The space debris management and alleviation in the microgravity environment is a dynamic research theme of contemporary interest. Herein, we provide a theoretical proof of the concept of a lucrative energy conversion system that is capable of changing the space debris into useful powders in the International Space Station (ISS) for various bids. A specially designed broom is adapted to collect the space debris of various sizes. An optical sorting method is proposed for the debris segregation in the ISS by creating an artificial gravitational field. It could be done by using the frame‐dragging effect or gravitomagnetism. An induction furnace is facilitated for converting the segregated metal‐scrap into liquid metal. A fuel‐cell aided water atomization method is proposed for transforming the liquid debris into metal powder. The high‐energetic metal powders obtained from the space debris could be employed for producing propellants for useful aerospace applications, and the silicon powder obtained could be used for making soil for fostering the pharmaceutical‐flora in the space lab in the future aiming for the scarce‐drug discoveries for high‐endurance health care management. The proposed energy conversion system is a possible alternative for the space debris extenuation and its real applications in orbiting laboratories through the international collaboration for the benefits to humanity.

This full paper is focused on research into how educators might use concept mapping to explore and design learning experiences in a problem-based learning environment. Attempts to incorporate more open-ended, ill-structured experiences have increased but are challenging for faculty to implement because there are no systematic methods or approaches that support the educator in designing these learning experiences. In the reported work, we present an exploratory study toward a systematic approach for comparing and manipulating problems. The approach combines concept mapping with Jonassen’s characterization of problems and the forms of knowledge required to solve them. We explore manipulation pathways for a problem that can be pursued by an instructor who is interested in impacting the dimensions of structuredness and complexity. We compare similarities and differences among two problems taken from introductory aerospace engineering courses. We consider manipulation of structuredness and complexity and the change propagation in forms of knowledge and solution pathways.