The case for small space missions

Three orders of arguments are outlined to illustrate the importance of small missions. First, the classical reasons (one has to begin small, educational aspects, introduction to the space field) are summarized; then some thoughts are introduced on the efficacy and the efficiency of the effort invested (how expensive is a national project, and how advantageous the inevitable multinational cooperation); finally, a synopsis of the considerations about the need for cultural changes in the space program (the challenge of the coming era, the resulting needs, the philosophy of “small missions” and its contributions) is given.     

Funding for space - private finance for public space missions?

Private users of space capability are used to buying a service, not a spacecraft. The supplier builds, launches and operates the spacecraft and the users only pay for the service that they receive. Publicly funded users could benefit from the same approach. Transferring responsibility for the success of the mission to a true prime contractor who is best able to manage technical and programme risks can lead to significant reductions in costs and timescales, but demands changes in attitudes by governments, users, industry and space agencies.     

Emergency and rescue considerations for manned space missions.

Man in space is totally dependent upon spacecraft systems. particularly those providing Environmental Control and Life Support (ECLS). It is therefore required that the design of manned spacecraft systems include provision for backup emergency and rescue modes of operation to insure adequate crew safety margin. This paper discusses safety, emergency and rescue provisions included in the Space Transportation System (STS), with emphasis on ECLS subsystems. Similar discussion is included for systems projected for use in future, extended duration manned space missions.     

中国航天固体火箭技术的发展

叙述了20世纪50年代以来中国航天固体火箭推进技术的发展历程,介绍了9种最具代表性的固体火箭发动机的技术特征、研制过程、地面试验和飞行情况,这些发动机分别应用于中国的探空火箭、运载火箭上面级和应用卫星变轨系统。文中还简要地评述了中国固体推进各单项技术的发展水平。     

Situation studies of aes orbits for solar-Earth space experiments

The questions on the orbit selection for studying various areas of the Earth magnetosphere are discussed. The method of the orbit selection is based on the use of orbital tori and on the construction of areas of orbit set intersection with model surfaces, forming specific areas in the near Earth space: bow shock (BSh), magnetopause (MP) neutral sheet in the magnetosphere tail, cusp etc. Intersections of the “Prognoz” 1–8 orbit set with model surfaces BSh and MP are shown.     

Psychology and culture during long-duration space missions

The objective of this paper is twofold: (a) to review the current knowledge of cultural, psychological, psychiatric, cognitive, interpersonal, and organizational issues that are relevant to the behavior and performance of astronaut crews and ground support personnel and (b) to make recommendations for future human space missions, including both transit and planetary surface operations involving the Moon or Mars. The focus will be on long-duration missions lasting at least six weeks, when important psychological and interpersonal factors begin to take their toll on crewmembers. This information is designed to provide guidelines for astronaut selection and training, in-flight monitoring and support, and post-flight recovery and re-adaptation.     

Rapid assessment of radiobiological doses for terrestrial and interplanetary space missions

This paper presents the doses levels expected in orbits in chart form, covering the range 300-800 km of altitude and 0-90 degrees of inclination behind shieldings similar to the Hermes spacecraft and the EVA spacesuit matter distributions. These charts allow users to rapidly find the radiobiological dose received in the most critical organs of the human body either in normal situations or during a large solar event. Outside the magnetosphere, during interplanetary or lunar missions, when the dose received during crossing of the radiation belts become negligible, the dose is due to galactic cosmic rays (GCR) and solar flares. The correct radiobiological assessment of the components of this radiation field becomes a major problem. On the Moon a permanent ground-based station can be shielded by lunar materials against meteoroids and radiations. The radiobiological hazard, essentially linked to the solar flare risk during the transfer phase and the extra-station activities, may be solved by mission planning. For interplanetary flights the problem comes from both increased risk of solar events and from the continuous exposure to GCR. These energetic particles cannot be easily stopped by shieldings; cost considerations imply that more effective materials must be used. Impact on the vehicle design and the mission planning is important.     

Risks of radiation cataracts from interplanetary space missions

Recognition of the human risks from radiation exposure during manned missions in deep space has been fostered by international co-operation; interagency collaboration is facilitating their evaluation. Further co-operation can lead, perhaps by the end of this decade, to an evaluation of one of the three major risks, namely radiation cataractogenesis, sufficient for use in the planning of the manned mission to Mars.     

Astromedicine and astrolaw: Emerging issues for advanced missions beyond Earth orbit

It is generally agreed within the scientific community that provision of appropriate medical facilities and administration of quality health care to astronauts are of great importance. However, for the more complex and remote missions envisaged for the future, issues of liability, responsibility and damage relating to medical practice may take on a greater significance and will need to be addressed. The author briefly reviews potential issues which may arise in the context of medical emergencies, crew autonomy and environmentally altered physiological status which characterize some projected advanced space missions and argues that the law of outer space will need to be expanded to take account of them.     

Bioconversion systems for food and water on long term space missions

An imperative for prolonged Space flight missions is the conservation of resources. Extensive resupply could pose technological and logistical challenges for those responsible for the management and successful completion of the mission. Therefore, the biological waste water reclamation system (BWWR) which requires little or no expendable supplies and the waste cellulose to edible mushroom conversion system (CMCS) which is conceived as a low energy crop waste recycling system are prototype instruments which have been conceived as solutions to the mission resupply problem. Out tests, conducted with relatively crude devices based on the original concepts, indicate that further research on the basic principles underlying the systems and refinement of the engineering designs will lead to hardware with the potential to satisfy the requirement for minimal re-supply while providing recycled water and edible mushrooms.     

Small satellite's role in future hyperspectral Earth observation missions

Along with various advanced satellite onboard sensors, an important place in the near future will belong to hyperspectral instruments, considered as suitable for different scientific, commercial and military missions. As was demonstrated over the last decade, hyperspectral Earth observations can be provided by small satellites at considerably lower costs and shorter timescales, even though with some limitations on resolution, spectral response, and data rate. In this work the requirements on small satellites with imaging hyperspectral sensors are studied. Physical and technological limitations of hyperspectral imagers are considered. A mathematical model of a small satellite with a hyperspectral imaging spectrometer system is developed. The ability of the small satellites of different subclasses (micro- and mini-) to obtain hyperspectral images with a given resolution and quality is examined. As a result of the feasibility analysis, the constraints on the main technical parameters of hyperspectral instruments suitable for application onboard the small satellites are outlined. Comparison of the data for designed and planned instruments with simulation results validates the presented approach to the estimation of the small satellite size limitations. Presented analysis was carried out for sensors with conventional filled aperture optics.     

A low-cost femtosatellite to enable distributed space missions

A new class of distributed space missions is emerging which requires hundreds to thousands of satellites for real-time, distributed, multi-point sensing to accomplish long-awaited remote sensing and science objectives. These missions, stymied by the lack of a low-cost mass-producible solution, can become reality by merging the concepts of distributed satellite systems and terrestrial wireless sensor networks. However, unlike terrestrial sensor nodes, space-based nodes must survive unique environmental hazards while undergoing complex orbital dynamics. A novel sub-kilogram very small satellite design is needed to meet these requirements. Sub-kilogram satellite concepts are developing elsewhere, such as traditional picosatellites and microengineered aerospace systems. Although viable technical solutions, these technologies currently come at a high cost due to their reliance on high-density technology or custom manufacturing processes. While evaluating these technologies, two untapped technology areas became evident that uniquely encompass low cost and mass producibility by leveraging existing commercial production techniques: satellite-on-a-chip (SpaceChip) and satellite-on-a-printed circuit board (PCBSat). This paper focuses on the design, build, and test results of a prototype PCBSat with a prototype unit cost less than $300. The paper concludes with mission applications and future direction.     

Coping with space motion sickness in Spacelab missions.

A substantial number of persons, around 75%, making their first transition into orbital flight will need to adapt to this unique environment. The two most powerful instruments in the prevention of space motion sickness reside in the selection process and in acquiring adaptation-prelaunch. Today, neither of these means is practical. One logical alternative is to administer preventative medication to all or none. One candidate drug is a high-potency transdermal therapeutic system (TTS)-scopolamine. This is marketed in the nature of a patch that is affixed to the skin behind the ear 12 hr before need and delivers scopolamine into the blood stream for three days. We are systematically evaluating all claims for its high potency and low side effects. We are also evaluating new antimotion sickness remedies and new combinations of homergic drugs.     

Psychosocial issues affecting crews during long-duration international space missions

Psychosocial issues can negatively impact on crew performance and morale during long-duration international space missions. Major psychosocial factors that have been described in anecdotal reports from space and in studies from analog situations on Earth include: 1) crew heterogeneity due to gender differences, cultural issues, and work experiences and motivations; 2) language and dialect variations; and 3) task versus supportive leadership roles. All of these factors can lead to negative sequelae, such as intra-crew tension and cohesion disruptions. Specific sequelae that can result from single factors include subgrouping and scapegoating due to crew heterogeneity; miscommunication due to major or subtle language differences; and role confusion, competition, and status leveling due to inappropriate leadership role definition. It is time to conduct research exploring the impact of these psychosocial factors and their sequelae on space crews during actual long-duration international space missions.     

Ensuring of long operation life of the orbiting station EVA space suit

Russia has gained a lot of experience in operating the space suits (SS) during the extravehicular activities (EVA) by the crews of SALYUT-6, SALYUT-7 and MIR orbiting stations. A total of 21 Orlan-type space suits of various models were operated onboard the orbiting stations (OS) during almost 20 years period. Some of these space suits served up to 3 years in orbit. The paper reviews special features of long SS operation (without return to the Earth) onboard an orbiting station as well as the problems associated with SS repeated use by several crews. An analysis of measures to support solving of the problems of SS long stay and reliable operation onboard the orbiting station is made: selection of a corresponding SS type and separate elements design; selection of the materials; routine and preventive maintenance; development tests. The advantages of the space suit of a semi-rigid type for solving the above problems are shown. The paper includes a short analysis of space suits' operation onboard the Russian orbiting station MIR, and some restuts of inspection of the Orlan-DMA space suit returned to the Earth from orbit by STS-79 alter long operation in orbit. Recommendations on further improvement of the space suits for EVA operations in the International Space Station (ISS) are given.     

Large-size space debris flyby in low earth orbits

the analysis of NORAD catalogue of space objects executed with respect to the overall sizes of upper-stages and last stages of carrier rockets allows the classification of 5 groups of large-size space debris (LSSD). These groups are defined according to the proximity of orbital inclinations of the involved objects. The orbits within a group have various values of deviations in the Right Ascension of the Ascending Node (RAAN). It is proposed to use the RAANs deviations' evolution portrait to clarify the orbital planes’ relative spatial distribution in a group so that the RAAN deviations should be calculated with respect to the concrete precessing orbital plane of the concrete object. In case of the first three groups (inclinations i = 71°, i = 74°, i = 81°) the straight lines of the RAAN relative deviations almost do not intersect each other. So the simple, successive flyby of group’s elements is effective, but the significant value of total ΔV is required to form drift orbits. In case of the fifth group (Sun-synchronous orbits) these straight lines chaotically intersect each other for many times due to the noticeable differences in values of semi-major axes and orbital inclinations. The intersections’ existence makes it possible to create such a flyby sequence for LSSD group when the orbit of one LSSD object simultaneously serves as the drift orbit to attain another LSSD object. This flyby scheme requiring less ΔV was called “diagonal.” The RAANs deviations’ evolution portrait built for the fourth group (to be studied in the paper) contains both types of lines, so the simultaneous combination of diagonal and successive flyby schemes is possible. The value of total ΔV and temporal costs were calculated to cover all the elements of the 4th group. The article is also enriched by the results obtained for the flyby problem solution in case of all the five mentioned LSSD groups. The general recommendations are given concerned with the required reserve of total ΔV and with amount of detachable de-orbiting units onboard the maneuvering platform and onboard the refueling vehicle.     

Architectural design for space tourism

The paper describes the main issues for the design of an appropriately planned habitat for tourists in space.Due study and analysis of the environment of space stations (ISS, MIR, Skylab) delineate positive and negative aspects of architectonical design. Analysis of the features of architectonical design for touristic needs and verification of suitability with design for space habitat.Space tourism environment must offer a high degree of comfort and suggest correct behavior of the tourists. This is intended for the single person as well as for the group. Two main aspects of architectural planning will be needed: the design of the private sphere and the design of the public sphere.To define the appearance of environment there should be paid attention to some main elements like the materiality of surfaces used; the main shapes of areas and the degree of flexibility and adaptability of the environment to specific needs.     

Social and cultural issues during Shuttle/Mir space missions.

A number of interpersonal issues relevant to manned space missions have been identified from the literature. These include crew tension, cohesion, leadership, language and cultural factors, and displacement. Ground-based studies by others and us have clarified some of the parameters of these issues and have indicated ways in which they could be studied during actual space missions. In this paper, we summarize some of our findings related to social and cultural issues from a NASA-funded study conducted during several Shuttle/Mir space missions. We used standardized mood and group climate measures that were completed on a weekly basis by American and Russian crew and mission control subjects who participated in these missions. Our results indicated that American subjects reported more dissatisfaction with their interpersonal environment than their Russian counterparts, especially American astronauts. Mission control personnel were more dysphoric than crewmembers, but both groups were significantly less dysphoric than other work groups on Earth. Countermeasures based on our findings are discussed which can be applied to future multicultural space missions.     

Vibrografic signs of autonomous muscle tone studied in long term space missions

Signs of resting muscle tone, assessed by cardiac driven microvibrations (MV), were studied in two cosmonauts during long term space missions on the Russian MIR station. In the 1 g environment, MV showed the typical 7-13 Hz resonance oscillations triggered by the heart beat. In 0 g, these pulsations were damped and the waveform became similar to an acceleration ballistocardiogram. If resting tone was slightly increased by extending the arm in 0 g, the resonance oscillations reappeared in most cases. By means of a simple vibromechanic analog it is demonstrated that the elastic component of muscle has to be reduced during the fully relaxed state in 0g.