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Trajectories of Interplanetary Flights
Published in G.A. Gurzadyan, Theory of Interplanetary Flights, 2020
From the point of view of celestial mechanics, interplanetary flight implies first of all, passage of a space apparatus into the zone of the Solar gravity after its departure from the Earth and escape from the zone of action, so that the motion of the apparatus is determined by the influence of the Sun. The apparatus escaping from the Earth thereby becomes an independent member of the Solar system, and therefore its motion within the interplanetary space can, to a first approximation be described by the laws of the two-body problem with the Sun as the central body (Celnikier, 1993). As has already been described, that motion around the central body must take place according to a conical section – an ellipse, parabola or hyperbola.
Mars Surface Exploration via Unmanned Aerial Vehicles
Published in Shashi Bhushan, Manoj Kumar, Pramod Kumar, Renjith V. Ravi, Anuj Kumar Singh, Holistic Approach to Quantum Cryptography in Cyber Security, 2023
Manjula Sharma, Akshita Gupta, Sachin Kumar Gupta
For an interplanetary mission, radio frequency (RF) waves are used to communicate to and from the satellite. They are usually sent at frequencies in the GHz range. Telemetry, Tracking, and Control (TT&C) and data communications can be interrupted at any time during the satellite's lifespan, forcing the attacker to gather additional data and launch attacks on the ground segment. The most popular methods of data communication disruption are jamming, hijacking, eavesdropping, and spoofing.
The individual and combined effects of spaceflight radiation and microgravity on biologic systems and functional outcomes
Published in Journal of Environmental Science and Health, Part C, 2021
Jeffrey S. Willey, Richard A. Britten, Elizabeth Blaber, Candice G.T. Tahimic, Jeffrey Chancellor, Marie Mortreux, Larry D. Sanford, Angela J. Kubik, Michael D. Delp, Xiao Wen Mao
GCR nuclei originate outside our solar system and are high-LET (linear energy transfer), ions with enough energy to easily pass through typical spacecraft with minimal energy loss.58 The considerable ionization power of GCR ions makes them the primary antagonist for possible late effects to multiple physiologic systems. During spaceflight in interplanetary space, every cell nucleus will be traversed by a hydrogen ion or delta ray every few days, and by the heavier GCR ion every few months.59,60 Despite their relatively low frequency, the heavy ions contribute a significant amount to the GCR dose that astronauts will incur outside of LEO. Thicker shielding could provide protection but is limited by the capabilities of spacecraft launch systems. In fact, studies have shown that even if the amount of shielding is increased (e.g., aluminum), there will not be a significant reduction of the intra-vehicular radiation dose.57,60,61 Astronauts currently on the International Space Station (ISS) are exposed to on average about 1 mSv/day, and even have emergency plans to shield themselves with water bags should an SPE occur. As we travel further outside of LEO, however, it is expected that this daily dose will increase by a factor of 2-3 with limited additional protective measures for SPEs due to spacecraft design and consumables.57,62,63