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Rusty Mars
Published in Thomas Hockey, Jennifer Lynn Bartlett, Daniel C. Boice, Solar System, 2021
Thomas Hockey, Jennifer Bartlett, Daniel Boice
What Viking 1 and 2 revealed about martian weather and scenery was all well and good, but their principal mission was to search for signs of life. Nobody really expected a martian creature to run before their cameras. Nevertheless, what about simpler life, for instance, bacteria? Are they protected from incoming radiation by the martian soil? To this end, the Vikings had a mechanical arm that dug samples of martian dirt and placed them in a special Labeled Release Experiment [LRE] box aboard the craft. This chamber contained nutrients on which biologists hoped martian microbes might gorge themselves. Then, as all life forms eventually must after a good meal, the microbes would—to put it delicately—change the chemistry of the chamber. The instrument could measure such a chemical change and relay the results to the awaiting scientists back on the Earth (Figure 8.15).
The Interstellar and Interplanetary Medium
Published in Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff, Radiation and Radioactivity on Earth and Beyond, 2020
Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff
Where this event occurred, and what the parent body was, remains a matter of speculation. Lunar exploration shows that the Moon can be ruled out. Our satellite has been a geologically dead body for quite a while, the last lava flux having occurred some 2500 million years ago. By successive elimination Mars is left as the most plausible site. Observations of its surface show that lava flows occurred there in the relatively recent past, about 200 million years ago. A possible way in which material could be ejected into space would be by powerful meteoritic impact resulting in instantaneous evaporation of a large amount of frozen water in the Martian soil, followed by explosive steam propulsion of fragments into space. We may have been handling the chunks of Martian rocks for years without realizing it!
An Introduction to Control Systems
Published in Arthur G.O. Mutambara, Design and Analysis of Control Systems, 2017
The Mars Surveyor 2001 Lander is scheduled for launch on April 10, 2001. It will land on Mars on Jan. 22, 2002, if launched on schedule. The 2001 Lander will carry an imager to take pictures of the surrounding terrain during its rocket-assisted descent to the surface. The descent imaging camera will provide images of the landing site for geological analyses, and will aid in planning for initial operations and traverses by the Rover. The 2001 Lander will also be a platform for instruments and technology experiments designed to provide key insights into decisions regarding successful and cost-effective human missions to Mars. Hardware on the Lander will be used for an insitu demonstration test of rocket propellant production using gases in the Martian atmosphere. Other equipment will characterize the Martian soil properties and surface radiation environment. The Lander is shown in Figure 1.21.
Terrain-aware traverse planning for a Mars sample return rover
Published in Advanced Robotics, 2021
Moreover, for a rover on Martian soil, assumptions can be made that the confining pressure is negligible and the vertical stress is simply the load of the vehicle [38], as illustrated in Figure 6. With these assumptions, the Mohr circle at failure (i.e. the circle whose tangent is the Mohr-Coulomb envelope) gives the maximum shear stress (or wheel rotation at constant velocity [38]) and the maximum load (or weight) the soil can bear, which is by definition the ultimate bearing capacity (Figure 6), which is valuable additional information to have. While the ultimate bearing capacity cannot identify a soil, it is a useful factor to know to avoid situations where the rover might be at great risk, such as when Spirit got embedded in sand.
Biomolecular self-assembly under extreme Martian mimetic conditions
Published in Molecular Physics, 2019
Harrison Laurent, Alan Soper, Lorna Dougan
When we start to consider the hostile environment of the subsurface Martian water, we must speculate on its likely contents. It is known that Martian soil contains magnesium perchlorate (Mg(ClO4)2) [7,10,13,14], hence it is reasonable to assume that this is also present in the subsurface water. However, there exists no direct evidence of what its concentration may be. While it is shown that Mg(ClO4)2 can become highly bactericidal when irradiated by UV flux levels consistent with what would be expected at the Martian surface [19], or when desiccated [20], this subsurface briny water would offer an environment where these bactericidal effects would be significantly diminished. It has been shown that several organisms, such as the microorganism Halorubrum lacusprofundi isolated from Deep Lake in Antarctica, are capable of anaerobic growth in 0.04 M Mg(ClO4)2 [21,22], hence the presence of this salt alone does not eliminate the possibility for life. Both ionic species in this compound are highly chaotropic and therefore act as powerful protein denaturants due to their strong interaction with the surfaces of biological molecules [23–25].