Outer Space Missions Research Articles

Drafting a Cybersecurity Standard for Outer Space Missions: On Critical Infrastructure, China, and the Indispensability of a Global Inclusive Approach

Despite limited progress within international institutions, the need for articulating a regulatory framework for cyber operations in outer space is becoming a pressing concern. One precondition for regulation is to share cybersecurity and outer-space common terminology that can inform the negotiation of standards, policies and laws. While the UN Institute for Disarmament Research has recently issued a baseline policy glossary, binding technical definitions are missing, and the lack of a binding international cybersecurity regime adds to the obsolescence of a binding outer-space regime tracing back to half a century ago. As the IEEE SA embarks on the drafting of the first-ever technical standard for cybersecure-by- design outer-space missions, scoping and conceptual challenges abound. Technical standards are US-centred, non-binding, engineering-intensive exercises, where lawyers and Asian jurisdictions are only marginally involved; nevertheless, as China’s framework for cybersecurity is refined and its involvement in outer-space policing deepens, its disengagement from Western-driven standard-setting bodies appears unsustainable. Drawing on the specific challenge of defining what makes a cyber system ‘mission-critical’, I expose the necessity to examine how domestic cybersecurity laws from a diverse range of States identify ‘critical’ information infrastructure. Generalising therefrom, I advocate a jurisdictionally inclusive process that combines American supremacy in technical standard-setting for outer-space missions with Chinese normative contributions to cybersecurity regulation, including on data localisation and mandatory multilevel cyber-hygiene requirements. I further argue that involving legal experts from a diverse range of jurisdictions and sociolegal cultures may enhance the global reception of standardisation outputs, thus securing higher degrees of voluntary compliance therewith. This could foster cooperation and promote regional and global satellite cybersecurity.

Drafting a Cybersecurity Standard for Outer Space Missions: On Critical Infrastructure, China, and the Indispensability of a Global Inclusive Approach

Drafting a Cybersecurity Standard for Outer Space Missions: On Critical Infrastructure, China, and the Indispensability of a Global Inclusive Approach

Nature-Inspired Concepts for High-Power Electric Propulsion Systems

The development of new space missions and the growing interest in space exploration have created an urgent need to develop high-thrust propulsion systems capable of propelling spacecraft far beyond the Earth and the solar system for long periods. Electric propulsion can potentially enable space missions to reach speeds thousands of times greater than conventional high-thrust chemical rockets. However, high speed comes at the cost of low power-to-thrust efficiency when considering propulsion systems as a whole, including the power generation system, transmission lines, and thrusters, which prevents high thrust from being achieved with any conceivable power system, resulting in long acceleration times. In addition, modern electric propulsion systems rely on external power sources that suffer significant power transfer losses at the high power levels required for high thrust levels. In addition, modern electric propulsion systems suffer from a number of critical physical and engineering problems that affect thrust levels and longevity. In addition, modern electric propulsion systems do not follow the principles of generation and acceleration of plasma flow that can be observed in space and potentially borrowed for artificial applications. This paper discusses several promising electrodeless plasma thruster concepts for high-power, high-thrust electric propulsion systems based on a combined power source/power converter/thruster architecture. These concepts have the potential to overcome modern limitations of high-power electric propulsion systems and enable new outer space missions that would not be possible with conventional thrusters.

Stability of Antimicrobial Drug Molecules in Different Gravitational and Radiation Conditions in View of Applications during Outer Space Missions.

The evolution of different antimicrobial drugs in terrestrial, microgravity and hypergravity conditions is presented within this review, in connection with their implementation during human space exploration. Drug stability is of utmost importance for applications in outer space. Instabilities may be radiation-induced or micro-/hypergravity produced. The antimicrobial agents used in space may have diminished effects not only due to the microgravity-induced weakened immune response of astronauts, but also due to the gravity and radiation-altered pathogens. In this context, the paper provides schemes and procedures to find reliable ways of fighting multiple drug resistance acquired by microorganisms. It shows that the role of multipurpose medicines modified at the molecular scale by optical methods in long-term space missions should be considered in more detail. Solutions to maintain drug stability, even in extreme environmental conditions, are also discussed, such as those that would be encountered during long-duration space exploratory missions. While the microgravity conditions may not be avoided in space, the suggested approaches deal with the radiation-induced modifications in humans, bacteria and medicines onboard, which may be fought by novel pharmaceutical formulation strategies along with radioprotective packaging and storage.

Timepix3: Temperature influence on X-ray measurements in counting mode with Si sensor

The Timepix3 radiation imaging and particle tracking detector is the direct successor to the Timepix semiconductor detector developed in CERN. The Timepix ASIC chip (256 × 256 pixels with a pitch of 55μm provides the possibility to operate each of the 65536 pixels in one of the following modes: (1) event counting (Medipix mode); (2) energy measurement (Time over Threshold — ToT mode); and (3) measurement of the interaction time (Time of Arrival — ToA mode). The Timepix3 chip of the new generation introduces the ability to measure ToT and ToA simultaneously and also the event-based readout where each hit pixel is read out immediately after the hit. This detector can be used in a variety fields of science including particle physics, X-ray imaging as well as medicine and space science. With regards to the wide application possibilities of this detector, we investigate the properties of the detector in the temperature range from −20°C to ＋80°C. This temperature range spans the majority of laboratory conditions as well as requirements for most of outer space missions. This paper describes thermal-vacuum testing of the most common 300µm Si detector with AdvaPIX readout interface in the counting mode. The detector was stabilised under various thermal conditions in a thermal vacuum chamber and subsequently exposed to characteristic X-ray radiation of 5 elements in the energy range of 4–24keV. It was found that the absolute measurement accuracy of higher energies is more affected by higher temperature (up to 0.8keV@17.48keV) and relative error of Timepix3 accuracy is inversely proportional to the incident X-ray energy. The relative precision is kept in the range of 6% for temperatures from −20°C to ＋60°C with significant change at ＋80°C.

Morphology analysis of tracks in the aerogels impacted by hypervelocity irregular particles

Abstract As an attractive collector medium for hypervelocity particles, combined with outstanding physical properties and suitable compositional characteristics, SiO2 aerogel has been deployed on outer space missions and laser shock-loaded collection experiments. In this paper, impact experiments were conducted to understand the penetration process of irregular grains, irregular Al2O3 grains with two different sizes and speeds (~110 μm@7 km/s, ~251 μm@2.3 km/s) at various density silica aerogels. By classifying the shapes of projectile residues and tracks, the morphology of tracks was analyzed. It was observed that there were several kinds of typical tracks in the penetration of irregular grains, accompanied by residues with the shapes of near-sphere, polyhedron, streamlined body wedge, and rotator. The rotational behavior was demonstrated by the final status of one flake projectile as direct evidence. In addition, there was no obvious relationship between the track length and experimental parameters, which may be caused by the uncertain interaction between aerogels and irregular particles. In addition, it confirmed the existence of fragmentation, melting situation by observing the shape of the impact entrance hole. At the same time, optical coherence tomography was used to observe the detail of tracks clearly, which provided a method to characterize the tracks nondestructively.

Atmospheric Neutron Monitoring through Optical Fiber-Based Sensing

The potential of fiber-based sensors to monitor the fluence of atmospheric neutrons is evaluated through accelerated tests at the TRIUMF Neutron Facility (TNF) (BC, Canada), offering a flux approximatively 109 higher than the reference spectrum observed under standard conditions in New York City, USA. The radiation-induced attenuation (RIA) at 1625 nm of a phosphorus-doped radiation sensitive optical fiber is shown to linearly increase with neutron fluence, allowing an in situ and easy monitoring of the neutron flux and fluence at this facility. Furthermore, our experiments show that the fiber response remains sensitive to the ionization processes, at least up to a fluence of 7.1 × 1011 n cm−², as its radiation sensitivity coefficient (~3.36 dB km−1 Gy−1) under neutron exposure remains very similar to the one measured under X-rays (~3.8 dB km−1 Gy−1) at the same wavelength. The presented results open the way to the development of a point-like or even a distributed dosimeter for natural or man-made neutron-rich environments. The feasibility to measure the dose caused by the neutron exposure during stratospheric balloon experiments, or during outer space missions, is presented as a case study of a potential future application.

Simple deceleration mechanism confirmed in the terminal hypervelocity impacted tracks in SiO2 aerogel

As an attractive collector medium for hypervelocity particles, SiO2 aerogel has been deployed on outer space missions. Aiming at quantifying the complicated relationship between the penetration track and the residual grains, many attempts have been made on hypervelocity experiments and models. However, models were difficult to accord strictly well with experimental data attributed to many uncertainties including thermal effects, aerogel accretions and projectile ablation during the penetration. In this paper, impact experiments were conducted at various density silica aerogels (50∼120 kg·m−3) with regular soda-lime glass beads as projectiles. Varying degrees of thermal effects happened around and along track was observed by scanning electron microscopy. That energy distribution in the track released by hypervelocity projectile has a decreasing change. The regular data of the terminal A-β type track (the track with combined features) was found according to A-type tracks classification based on the conditions of vapor model (Domínguez, 2009). Just considering for projectile overcoming the crushing strength with uniform deceleration, the simple mechanism was confirmed by the data fitted well with the snowplow model (Domínguez et al., 2004). The result after tracks classification is due to the terminal track with few thermal effects and aerogel accretions. In addition, other two types of tracks formation processes were discussed.

Antarctic station life: The first 15 years of mixed expeditions to the Antarctic

This study examined the experiences of women who lived and worked on remote and isolated Antarctic stations for up to 15 months at a time. The study employed purposeful sampling and a longitudinal – processual approach to study women's experiences over the first 15 years of mixed gender Antarctic expeditions. The retrospective analysis was based on a semi-structured interview administered to 14 women upon their return to Australia. The results showed that women referred to the natural physical Antarctic environment as one of the best aspects of their experience and the reason they would recommend the Antarctic to their friends as a good place to work. In describing the worst aspect of their experience, women referred to aspects of Antarctic station life, including: (i) the male dominated nature of station culture; (ii) the impact of interpersonal conflict, including gender based conflict and friction between scientists and trades workers; and (iii) the lack of anonymity associated with living and working with the same group of individuals, mainly men, for up to 12 months or more. The results are discussed within the context of the evolution of Antarctic station culture and recommendations are made in terms of the demography of expeditions, expeditioner selection and recruitment and the ongoing monitoring of Antarctic station culture. The study presents a framework that can be applied to groups and teams living and working in analogous isolated, confined and extreme work environments, including outer space missions.

Improvement of Interfacial Adhesion between UHMWPE Fiber and Epoxy Matrix Using Functionalized Graphitic Nanofibers

Ultra high molecular weight polyethylene (UHMWPE) fiber has advanced mechanical properties and excellent physical properties that include high effectiveness for cosmic radiation shielding, which is valuable for outer space missions. Unfortunately, poor interface in UHMWPE fiber—polymer composites hinders the structural integrity and safety, and restricts its effectiveness for the radiation shielding. In this study, we focus on the improvement of the adhesion property between the UHMWPE fiber and resin matrix by developing a nano-epoxy matrix through making a modification on the matrix with reactive graphitic nanofibers (r-GNFs). The interfacial adhesion between UHMWPE fiber and the nano-epoxy matrix with low concentrations of r-GNFs (0.15, 0.30, and 0.50 wt% ) is characterized by analyzing load—displacement curves from microbond tests. Study results show that crack initiation force, debonding force, debonding energy, and friction energy from the microbond tests increase considerably, due to the effective improvement of interfacial adhesion property by the nano-epoxy matrix. One-dimensional shear-lag analysis is applied for theoretical calculations. Calculated results on ultimate adhesive strength and external stress show agreement with the experimental results. Study results reveal that the nano-matrix with 0.30 wt% of r-GNFs is the most effective to improve adhesion properties between UHMWPE fiber and the epoxy.

Radiation protection guidelines for space missions.

The current radiation protection guidelines of the National Aeronautics and Space Administration (NASA) were recommended in 1970. The career limit was set at 4.0 Sv (400 rem). Using the same approach as in 1970 but current risk estimates, a considerably lower career limit would obtain today. Also, there is now much more information about the radiation environments that will be experienced in different missions. Furthermore, since 1970 women have joined the ranks of the astronauts. For these and other reasons, it was considered necessary to re-examine the radiation protection guidelines. This task has been undertaken by the National Council on Radiation Protection and Measurements Scientific Committee 75. Within the magnetosphere, the radiation environment varies with altitude and inclination of the orbit. In outer space missions, galactic cosmic rays, with the small but important heavy-ion component, determine the radiation environment. The new recommendations for career dose limits, based on lifetime excess risk of cancer mortality, take into account age at first exposure and sex. The career limits range from 1.0 Sv (100 rem) for a 24-y-old female up to 4.0 Sv (400 rem) for a 55-y-old male, compared with the previous single limit of 4.0 Sv (400 rem). The career limit for the lens of the eye has been reduced from 6.0 Sv (600 rem) to 4.0 Sv (400 rem).