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Physical Hazards of Space Exploration and the Biological Bases of Behavioral Health and Performance in Extreme Environments
Published in Lauren Blackwell Landon, Kelley J. Slack, Eduardo Salas, Psychology and Human Performance in Space Programs, 2020
Julia M. Schorn, Peter G. Roma
Radiation is energy emitted in the form of particles, electromagnetic waves, and/or rays. In the electromagnetic spectrum, radiation can be seen in the form of visible light and felt in the form of infrared radiation. High-energy photons, X-rays, and gamma rays are not visible to the naked eye, but can be observed with special telescopes. There are three kinds of space radiation: particles trapped in the Earth’s magnetic field, solar particle events (SPEs), and galactic cosmic rays (GCRs). SPEs occur when solar flares explode on the surface of the sun, as they release massive amounts of energy in the form of protons, electrons, and HZE particles (Cucinotta, Townsend, Wilson, Golightly, & Weyland, 1994). GCR comprises nuclei from atoms that have had their surrounding electrons stripped away and are travelling at nearly the speed of light. Importantly, radiation is physical—it has mass, and exposure to radiation means particles physically entering or passing through the body and causing damage at the tissue, cell, and DNA levels. Radiation naturally exists throughout the universe; however, the Earth’s protective atmosphere and magnetic field shield us from most of it. In deep space, just the background dose rate of radiation is even higher than that on the ISS, the sun’s 11-year cycle culminates in a rapid increase of SPEs, and there is little to no natural protection from radiation.
Reliability and Flight Qualification
Published in Hamid Hemmati, Near-Earth Laser Communications, 2020
The space radiation environment consists primarily of trapped particles in the Van Allen Radiation Belts, solar energetic particles (SEPs), and galactic cosmic rays (GCRs) (Armstrong and Colborn, 2000; Huston, 2002). Energetic electrons and protons trapped by the Earth's magnetic field and its geomagnetic tail surrounds the Earth. This region is commonly referred to as the Van Allen radiation belts (Webb and Greenwell, 1998). The belts have two primary zones. The inner belt extends in altitude from about hundreds of kilometers to about 6000 km, while the outer belt extends to about 60,000 km. The South Atlantic anomaly comprises a region of lower magnetic field strength that allows energetic particles to penetrate down to about 100 km. While protons and electrons populate the inner belt, the outer belt consists primarily of energetic electrons. Coronal mass ejections and solar flares produce intense bursts of SEPs, including protons and heavy ions (electrons are also included but typically an order of magnitude lower in flux) over the polar caps. GCRs originate from outside the solar system and are formed from diffusive shock acceleration of supernova remnants. Primary GCRs consist of protons, alpha particles and heavy-ion nuclei. GCR particles move perpendicular to the Earth's magnetic field lines and can be deflected at the equator and funneled toward the poles. In this manner, GCRs are most relevant at high altitude and high inclination, polar orbits (Suparta, 2014).
Overview of the NASA ETDP RHESE Program
Published in John D. Cressler, H. Alan Mantooth, Extreme Environment Electronics, 2017
Though sources of space radiation are well understood and characterized, the problem still remains of how to protect the spacecraft, its occupants, and its electronics from the deleterious effects experienced when encountering space radiation. Multiple solutions exist that provide some level of protection. The most basic solution is to provide material shielding for the radiation-sensitive components of the spacecraft. By including additional material around the component to be protected, there is a much greater chance that a high-energy particle will be stopped via its interaction with the shielding material prior to reaching the component. The obvious problem with using shielding on a spacecraft is the mass penalty paid when attempting to place the entire system in orbit. One interesting approach to shielding includes the strategy for a manned mission to carry the potable and wastewater in locations that provide maximal radiation shielding [11] thus allowing the water to serve two purposes. It should also be realized that shielding will protect from lower-energy particles, but higher-energy particles may penetrate the shielding regardless of its practical thickness. Shielding also introduces the risk of induced Bremsstrahlung, or secondary, radiation caused by the interaction of high-energy particles with the constituent particles of the shielding material.
Why Human Enhancement is Necessary for Successful Human Deep-space Missions
Published in The New Bioethics, 2019
Konrad Szocik, Martin Braddock
Space radiation includes particles around the Earth’s magnetosphere in Van Allen Belts, SPE4 and galactic cosmic rays/radiation (GCR). GCR contains 1% of high-energy heavy ions (HZE particles), 90% of high energy protons and 9% of helium particles (Durante and Cucinotta 2008). Space radiation includes mostly protons and heavy ions and is qualitatively different from Earth radiation which comprises γ rays, β rays and α-rays. Space radiation, comprised of mostly high linear energy transfer (LET) particles causes greater health damages than radiation on Earth (Sion 2011). In addition to the killing effect of radiation and the potential for cell repair at low, longer exposures compared with high and shorter exposures, one additional factor is the impact of secondary radiation in spacecraft (Ohnishi et al. 2002). The Earth’s inner radiation belt contains only ionizing protons because of the protective impact of magnetosphere and atmosphere and has not shown to be problematic when traversed quickly as with the Apollo missions. Without the magnetosphere, life on Earth would likely not exist on the surface and more probably exist in subsurface forms. The radiation received on the Martian surface includes GCR, SPE, secondary particles and albedo particles reflected from the regolith (Matthiä et al. 2017).
Study on amplitude of the noise power spectrum for nano-strained Si NMOSFET
Published in Radiation Effects and Defects in Solids, 2022
Minru Hao, Min Shao, Yan Zhang, Lina Duan
The strained Si technology has high carrier mobility, adjustable bandgap and compatibility with the existing Si technology, so it is one of the important ways to improve strained integration technology (1–4). With the rapid development of aerospace technology, especially in high-tech fields, such as outer space technology, more and more semiconductor devices and integrated circuits need to work in space radiation environments (5–8). When these high-performance electronic components work in this space environment, they will always be affected by space radiation, which may significantly reduce the system’s reliability (9–12). On the one hand, the performance of electronic components has been dramatically improved with the rapid development of microelectronics technology. On the other hand, the failure efficiency has been highly reduced to , and it is difficult to select the components with potential reliability risks using conventional detection methods. The high-energy radiation in space will cause several of defects in the device materials, posing a serious threat to the device's reliability. Noise is more sensitive and contains more defect information than traditional reliability characterization parameters (13–15). Noise characterization parameters play an increasingly important role in failure physical evaluation methods. At present, the research is mainly focused on the non-strained materials and the experimental test methods of MOS device noise and the lack of mature theoretical model support. In addition, the assumption of the existing model is relatively simple and unable to meet the quantitative requirements (16–18). There is little correlation analysis on the mechanism of radiation degradation of noise, and the degradation model is still not available.
Optimum conceptual design for the life support systems of manned spacecraft
Published in Cogent Engineering, 2020
M. Mahmoudi, A. B. Novinzadeh, F. Pazooki
To protect the crew from space radiation, specific shielding should be used. This is integrated into the crew’s safety system, which also contains a fire protection module. The crew’s safety and atmospheric management are essential subsystems in a manned spacecraft. The other three blocks can be customized or simplified in short-term and suborbital missions. They manage the water and food for the crew and collect the metabolic and operational waste in the capsule.