The astronaut and the robot : Short- and long-term scenarios for space technology

A series of major accidents - the explosion of the Space Shuttle Challenger, the destruction of Titan and Delta launchers, and failures of the Ariane rocket series - has led to a reexamination of Western space programmes. In the short term, all satellite launches have been delayed. This is not an insurmountable obstacle, although it will inevitably delay the first space-based tests of SDI hardware. The author outlines the growing gap between the immediate needs of organizations which launch satellites and the more uncertain ambitions of the ‘conquerors’ of space. The former are now bearing the costs of the latter, who are aiming at manned space flights and a human presence in space. In the longer term, these objectives have justifications other than simple industrial and commercial logic. The author suggests that an attempt should be made to reconcile immediate military and industrial needs with the human desire to overcome the ‘Icarus complex’ in the long-term future.     

The cost of space flight

Estimates of the cost of human space flight continue to generate controversy in the effort to set US space policy. Estimates vary widely, depending upon the position of the observer. This article identifies the real cost of major space flight programs and traces the heterofore unsuccessful efforts to cut the expense of space operations.     

Effects of long-duration space flight on target acquisition

The purpose of the study was to explore the effects of long-duration space flight on the acquisition of specific visual targets in the horizontal plane. Seven cosmonauts (4 high performance pilots and 3 non-pilots) who had flown between 186–198 days on Mir served as subjects. Baseline testing was performed 4 times prior to launch and 4 times following landing at different intervals totrack recovery. During testing the subjects were required to acquire targets that were randomly presented with both a head and eye movement using a time optimal strategy. Prior to flight two unique head movement strategies, related primarily to piloting experience, were used for target acquisition. Non-pilots employed a Type-I strategy consisting of high velocity head movements with large peak amplitudes, while high performance pilots used primarily low velocity, small amplitude head movements (Type-II) to acquire the targets (p<0.02). For both strategies peak head velocities increased as the angular distance to the target increased (p<0.01) resulting in greater discrimination between strategies for the 60° targets. While preflight eye velocity between strategies did not reach statistical significance, postflight testing revealed a decrease in eye velocity for Type-I compared with their preflight performance (p<0.02) for the 60° targets. Postflight, the Type-I group showed a decrease in head velocity (p<0.20) while the Type-II group compensated by increasing head velocity (p<0.02). Variability for both of the head and eye parameters tended to increase postflight for both types of strategies.     

Effects of prolonged space flight on rat skeletal muscle

The effect of a 20-day space flight on water, Na+, K+, Mg2+, Ca2+ and glycogen contents as well as on activities of glycogen metabolism enzymes--glycogen synthetase and glycogen phosphorylase--of rat skeletal muscles was studied. This data is regarded as an integral test characterizing the state of contractile tissue of the animals at the final stage of flight aboard biosatellites. The measurements indicate that there were no significant changes of cations and glycogen contents nor of the enzymic activities in fast-twitch muscles during the 20-day spaceflight. At the same time dehydration in these muscles was observed, which disappeared on the 25th postflight day. In slow-twitch antigravitational skeletal muscle (m. soleus) there was a decrease of K+ and increase of Na+ in the tissue contents. The changes disappeared at the end of the on-earth readaptation period. From the pattern of these observations, we can conclude that the 20-day space flight leads to some reversible biochemical changes of the rat skeletal muscles. A conclusion can be drawn about necessity of creating, aboard the spaceship, an artificial load on antigravitational skeletal muscles.     

Psychological adaptation and salutogenesis in space: Lessons from a series of studies

Individuals who adapt positively to an inhospitable or extreme environment can derive benefit from their experiences. This positive effect may include an initial improvement in mental health as someone adjusts to the environment (adaptation) as well as more sustained personal growth during the mission (salutogenesis). We review relevant findings from our prior work, including two post-mission surveys of astronauts and cosmonauts, and three studies of crewmembers during missions in a space station simulator, the Mir space station, and the International Space Station (ISS). We also present new analyses showing evidence for adaptation to ISS missions. This finding replicates our previous results from the simulation study, but this effect was not found on the Mir. A better understanding of psychological adaptation and salutogenesis during space flight should help us develop strategies to enhance crewmembers’ in-flight stress tolerance and post-flight adjustment.     

Status and efficacy of countermeasures to physiological deconditioning from space flight

The recent biomedical investigations conducted on the Space Shuttle and Spacelab have provided a wealth of biomedical information, including the ability to test the efficacy of proposed countermeasures. This achievement was made possible by the ability to conduct mechanistic and control-interventive studies simultaneously with a large number of individuals over a relatively brief period and to compare these data with results obtained from the Skylab missions. Comparisons between short- and long-duration results were limited to establishing trends or extrapolating from short-duration missions. To date, we have evaluated several protocols involving the lower-body negative pressure (LBNP) device, the bicycle-ergometer, the treadmill and preparations for body-fluid replenishment. In many instances, the traditional means of applying these protocols were not sufficient to protect against space-related deconditioning. This paper will review current countermeasures and compare their efficacy to that of existing protocols. Results from in-flight and ground-based experiments will be presented to illuminate the recommended protocols and procedures.     

Biomedical problems of EVA support during manned space flight to Mars

Current projects of manned missions to Mars are aimed to their realization in the second-third decades of this century. The purpose of this paper is to determine and review the main biomedical problems, that require a first and foremost decision for safety support of extravehicular activity (EVA) carried out by crewmembers of the Mars expedition. To a number of such problems the authors of the paper attribute a creation of adequate EVA equipment intended, first, for assembly of interplanetary spacecraft on the Earth orbit, performance of maintenance operations and scientific researches on the external surface of spacecraft during interplanetary flight and, secondly, for work on the Mars surface. New generation of space suits with low weight, high mobility and acceptable risk of decompression sickness must be as a central component of EVA equipment. The program for preparation to a Mars expedition also has to include special investigations in order to design the means and methods for a reliable protection of crew against space radiation, to elaborate the approach to medical monitoring and primary medical care during autonomous space mission, to maintain good health condition of crewmembers during EVA under the Mars gravity (0.38 g) after super long-term flight in weightlessness.     

Assessment of the efficacy of medical countermeasures in space flight

Changes in body fluids, electrolytes, and muscle mass are manifestations of adaptation to space flight and readaptation to the 1-g environment. The purposes of this paper are to review the current knowledge of biomedical responses to short- and long-duration space missions and to assess the efficacy of countermeasures to 1-g conditioning. Exercise protocols, fluid hydration, dietary and potential pharmacologic measures are evaluated, and directions for future research activities are recommended.     

Physiology, medicine, long-duration space flight and the NSBRI

The hazards of long-duration space flight are real and unacceptable. In order for humans to participate effectively in long-duration orbital missions or continue the exploration of space, we must first secure the health of the astronaut and the success of such missions by assessing in detail the biomedical risks of space flight and developing countermeasures to these hazards. Acquiring the understanding necessary for building a sound foundation for countermeasure development requires an integrated approach to research in physiology and medicine and a level of cooperative action uncommon in the biomedical sciences. The research program of the National Space Biomedical Research Institute (NSBRI) was designed to accomplish just such an integrated research goal, ameliorating or eliminating the biomedical risks of long-duration space flight and enabling safe and productive exploration of space. The fruits of these labors are not limited to the space program. We can also use the gained understanding of the effects and mechanisms of the physiological changes engendered in space and the applied preventive and rehabilitative methods developed to combat these changes to the benefit of those on Earth who are facing similar physiological and psychological difficulties. This paper will discuss the innovative approach the NSBRI has taken to integrated research management and will present some of the successes of this approach.     

Excretion of amino acids by humans during space flight

We measured the urine amino acid distribution patterns before, during and after space flight on the Space Shuttle. The urine samples were collected on two separate flights of the space shuttle. The first flight lasted 9.5 days and the second flight 15 days. Urine was collected continuously on 8 subjects for the period beginning 10 d before launch to 6 d after landing. Results: In contrast to the earlier Skylab missions where a pronounced amino aciduria was found, on shuttle the urinary amino acids showed little change with spaceflight except for a marked decrease in all of the amino acids on FD (flight day) 1 (p<0.05) and a reduction in isoleucine and valine on FD3 and FD4 (p<0.05). Conclusions: (i) Amino aciduria is not an inevitable consequence of space flight. (ii) The occurrence of amino aciduria, like muscle protein breakdown is a mission specific effect rather than part of the general human response to microgravity.     

载人航天测控通信系统

在原有卫星测控网的基础上规划设计的载人航天测控通信系统与国际标准接轨，通过国内外的地面测控站和遍布三大洋的四艘远洋测量船保证了地面与飞船的测量控制和通信，实现了多项关键技术突破。它不仅能满足载人航天任务的高可靠、高精度、高覆盖、高速率的需要，还能同时为30颗以上卫星提供测控通信支持，这标志着我国自主发展的航天测控通信技术达到了世界先进水平。     

Research into the effects of astronaut motion on the spacecraft: a review

The paper reviews the research that has been undertaken to understand and quantify the disturbance effects of the astronaut's motion inside and outside the spacecraft on the vehicle's attitude and acceleratory environment. In early investigations, the dynamic interaction of astronauts, modeled as point masses, and the spacecraft, modelled as a rigid body, was analyzed. Through ground-based experiments and the modeling of astronaut-induced forces and moments as stochastic processes, it became possible to estimate the magnitude and energy content of the loads produced by the astronaut. The first experiment in space to measure the astronaut-induced disturbances was conducted on the Skylab orbital station. Loads generated while performing routine operations were measured on board the Space Shuttle in 1994 and on the space station Mir in 1996–1997.     

Goals and preparation method for ground operations for the manned space flight Altair

The mission's success fully depends on the Payload Operations conducted during the space flight. The Ground Team has to be trained to assist the Space Crew, to replan the cosmonaut's activities when contingengies occurr onboard and to change or cancel Payload activities when required. In order to act efficiently during the mission, the Ground Team must be prepared in advance of the flight and able to operate special tools for tracking the mission's progress, anticipating problems and taking decisions in realtime.

This document sets out the approach for conducting such a preparation for Ground Operation. It will be focused on the Altaïr mission performed in July 1993 onboard the Russian Mir space station.     

Serotonin in individual hypothalamic nuclei of rats after space flight on biosatellite Cosmos 1129.

The experiment on Cosmos 1129 was based on our results obtained in rats exposed to single or repeated restrain stress in the laboratory. These results have convincingly demonstrated a significant increase of serotonin concentration (5-HT) in the hypothalamus in acutely stressed rats. This response, which was found also in the isolated hypothalamic nuclei, was diminished in repeatedly (40 times) immobilized rats. While the concentration of 5-HT was unchanged in the majority of the hypothalamic nuclei of animals subjected to cosmic flight, an increase was recorded only in the supraoptic nucleus (NSO) and a decrease in the periventricular nucleus. These findings demonstrate that only few areas of the hypothalamus respond to cosmic flight with changes of 5-HT concentration and suggest either that long-term cosmic flight cannot be an intensive stressor or that during the flight the rats became already adapted to its long-term effect. However, the exposure of flight rats to repeated immobilization stress resulted in a significant increase of 5-HT in the NSO, para-ventricular and dorsomedial (NDM) nuclei. It should be noted that we have never seen any changes of 5-HT concentration, tryptophan hydroxylase and monoamineoxidase activities in repeatedly (40 times) immobilized rats. On the other hand, the increase of 5-HT concentration in the NDM is a typical finding after seven exposures of rats to immobilization on Earth, daily for 150 min. In the experiment COSMOS 1129 such an increase of 5-HT concentration in the NDM was found not only in the flight group but also in the control group of rats subjected to five daily exposures of immobilization stress. With respect to these findings, the increased 5-HT concentrations observed in some isolated hypothalamic nuclei in the flight group of rats exposed after landing to repeated immobilization stress suggest that long-term space flight and the state of weightlessness do not represent a stressogenic factor with respect to the serotoninergic system in the hypothalamus.     

Results of studies on advanced winged space transportation systems

This paper reviews advanced space transportation studies that have been conducted at the NASA Langley Research Center over the past several years and presents the impact of technology on vehicle size and weight. The focus of this work has been on systems that could become operational in the late 1990s and beyond with the primary emphasis on winged vehicles, both single-stage-to-orbit and two-stage concepts.     

Haploid deletion strains of Saccharomyces cerevisiae that determine survival during space flight

This study identifies genes that determine survival during a space flight, using the model eukaryotic organism, Saccharomyces cerevisiae. Select strains of a haploid yeast deletion series grew during storage in distilled water in space, but not in ground based static or clinorotation controls. The survival advantages in space in distilled water include a 133-fold advantage for the deletion of PEX19, a chaperone and import receptor for newly- synthesized class I peroxisomal membrane proteins, to 77–40 fold for deletion strains lacking elements of aerobic respiration, isocitrate metabolism, and mitochondrial electron transport. Following automated addition of rich growth media, the space flight was associated with a marked survival advantage of strains with deletions in catalytically active genes including hydrolases, oxidoreductases and transferases. When compared to static controls, space flight was associated with a marked survival disadvantage of deletion strains lacking transporter, antioxidant and catalytic activity. This study identifies yeast deletion strains with a survival advantage during storage in distilled water and space flight, and amplifies our understanding of the genes critical for survival in space.     

Prevention of space flight induced soft tissue calcification and disuse osteoporosis.

This paper emphasizes the devastating effects of displacement of calcium during space flight, due to increased bone turnover.     

Study of the psychological adaptation of the crew during a 135 days space simulation

The purpose of this study is to examine human adaptation of a three members' crew during a 135 days MIR flight simulation and to compare and validate psychological methods for monitoring and support in flight. The main findings showed that isolation was not a key factor for the subjects who were more concerned by recreational activities, family, and work. The individual reactions to stress of the crew members were to project their problems on the others. These reactions had some consequences upon the group: Although the three subjects developed a weak tendency to "group think", one of the crew members was considered as less integrated to the group by the other two subjects, who, however, acted to protect (successfully) the general cohesion and mood of the crew. From a methodological point of view, baseline data predicted the difficulties that occurred for one of the crew member. Both quantitative and qualitative tools were adequate, although qualitative tests gave a closer approach to the actual situation that developed during the simulation.