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As scientific discovery and human presence push further into space, it is necessary to investigate the effects of spaceflight on physiological systems. Research into the effects of the space flight environment on the human body is still in its relative infancy. Although initial studies have indicated harmful effects of spaceflight environments on certain body systems, this phenomenon still needs illumination with regards to the female reproductive system. Better understanding of these consequences can change the way society views space travel and colonization of other planets. The spaceflight environment consists of at least two major factors that could confer negative effects on physiology, namely radiation and microgravity. In this experiment, uterine smooth muscle, or the myometrium, was analyzed in 6-month old female C57BL/6 mice that were exposed to 21 days of low dose/low dose rate whole-body radiation with γ-radiation using 57Co plates (0.04 Gy at 0.01 cGy/h) and/or simulated microgravity (via hind limb unloading). Tissue samples were harvested 4 months after the 21-day simulated spaceflight period. Following embedding, sectioning, and hematoxylin and eosin staining (H&E), the tissues were examined, and the average thicknesses of the myometrial layers were measured. Three types of measurements were made 1 – outer longitudinal layer, 2 – inner circular layer, and 3 –total muscle layer thickness (outer and inner combined). Two-way ANOVA statistical tests were used to compare the thicknesses of the myometrial muscle layers between the various treatment groups. A statistical difference was found between the thicknesses in the outer longitudinal layer of smooth muscle between the control animals and the unloaded animals (P: 0.051).

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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / This paper describes an approach to the implementation of an IF sampling digital receiver for low data rate command and telemetry applications in the NASA Goddard Spaceflight Tracking and Data Network (STDN) and Air Force Space-Ground Link System (SGLS). The digital design is targeted for an FPGA-based implementation and was written entirely in VHDL. Several size and clock reduction techniques are described which were utilized due to limited gate-array resources and power. The system-level design architecture is described followed by a discussion of algorithms and performance of critical stages in the receiver chain. Bit error performance of the prototype receiver is also presented. Finally, although this design is specifically targeted for a narrowband command and telemetry application, the methodology forms the basis of a configurable receiver for higher data rate applications.

Syftet med vår uppsats är att undersöka Sveriges möjligheter för att etablera kommersiell rymdfart och om detta är en realistisk framtida möjlighet. Vi tittar även på om vissa satsningar borde göras som ett komplement till detta, genom till exempel virtuella upplevelser från jorden. Utgångspunkten för att undersöka om etablering av kommersiell rymdfart är genomförbart i Sverige var att titta på Kirunas möjligheter att utvecklas till en mer etablerad turist- och rymdstad. Vi fokuserar främst på utvecklingsmöjligheter och rådande framtidsplaner för Sveriges enda rymdraketbas Esrange Space Center. Vi har i denna uppsats huvudsakligen använt oss av kvalitativa metoder i form av strukturerade och ostrukturerade intervjuer. Vi har intervjuat fem, för vår forskning, relevanta aktörer med sin unika koppling till rymden, muntligt och via mejl. Den kvantitativa metoden som vi använt bestod av en enkätundersökning som vi utförde med hundra respondenter under en veckas tid. Våra teorier bygger på fem olika teoretiska ramverk som bidragit till att undersöka och styrka vårt syfte genom att applicera dessa i rymdsammanhang. Teorierna visar hur man genom att använda olika framtidsscenarier som undersökningsmetod kan hjälpa forskarna att förutspå ett visst framtida utfall. De visar även människans behov av självförverkligande och längtan efter nya upplevelser tillsammans med de aspekter som kan påverka människor att ta till sig en ny innovation eller välja att avvisa den. Teorierna undersöker även de hot, styrkor, svagheter och möjligheter som kommersiell rymdfart står inför. En etablering av kommersiell rymdfart innebär flera svårigheter inom områden som säkerhet, miljö och ekonomi. Men om utvecklingen följer samma kurva som för den vanliga flygtrafiken kan det bli möjligt att resa till rymden för ett rimligt pris om cirka 50 år. Var rymdaktörerna slutligen väljer att etablera kommersiell rymdfart kommer indirekt bestämmas av kunderna, då deras efterfrågan styr var en rymdstation blir mest lönsam att etablera. För Kiruna, med Sveriges enda rymdbas, är det viktigt att arbeta aktivt och ambitiöst för att kunna erbjuda ett attraktivt resande för intresserade kunder. Tills man hittar tekniska lösningar på de hinder kommersiell rymdfart står inför kan cyberturism (virtual reality) vara ett substitut för att få uppleva rymden utan att behöva ta hänsyn till tid, plats, säkerhet eller ekonomi. / The purpose of this essay is to explore Sweden’s opportunities to establish commercial spaceflight and whether this is a realistic or unrealistic possibility in the future. We also looked at whether efforts should be made as a complement to this, for example through virtual experiences from Earth. One of our starting points was to investigate the opportunities and potential for Kiruna to develop to a more established tourist- and urban space town. To achieve this, we are primarily focusing on the development opportunities and current plans for the future of Sweden´s only spaceport Esrange Space Center. In this paper, we mainly used qualitative methods in the form of structured and unstructured interviews. We had interviews with five relevant parties for our research, both verbally and via email. The quantitative method we used consisted of a survey we did with one hundred respondents during a period of one week. The theories that have been used are four different theoretical frameworks which have helped us to investigate and strengthen our purpose by applying these into the context of space. They include how the use of future scenarios as a method of investigation could help scientists to predict a certain future outcome. Also the human need of total fulfillment and the longing for new experiences together with the aspects that can affect whether a person accepts a new innovation or decides to reject it. The theories also examines the threats, strengths, weaknesses and possibilities that commercial spaceflight is facing. The commercial space sector is facing curtain difficulties in terms of safety, environmental and economic issues. But if the development follow the same curve as for the regular air traffic it might be possible to travel to space for a reasonable price 50 years from now. Where space organizations ultimately choose to establish commercial spaceflight depends on the customers, since their demand will determine where they want to fly out from. For Kiruna, which is already hosting Sweden´s only spaceport it will be crucial to work hard to show ambition and provide attractive offers for their potential clients. Until technology provides us with the solutions preventing commercial spaceflight cyber Tourism (virtual reality) can be a substitute for visitors to experience space without the need to take account of time, location, security and economy.

Space exploration is a uniquely human activity. As humans continue to push the limits of exploring the unknown, they have sought knowledge supporting the sustenance of life in outer space. New technologies, advancements in medicine, and rethinking what it means to be a “community” will need to emerge to support life among the stars. Crews traveling beyond the Moon will rely on the development of new technologies to support the technological aspects of their missions as well as their quality of life while away from Earth. Likewise, through advancements in medicine, scientists will need to address remaining questions regarding the effects of long-duration spaceflight on the human body and crew performance. Space explorers must learn to utilize these new technologies and medical advancements while learning to adapt to their new environment in space and as a space community. It is important that researchers address these issues so that human survival beyond Earth is not only achievable but so that life among the stars is worth living and sustaining. This thesis addressed these issues in an attempt to extend the trajectory of space exploration to new horizons.

Les vols spatiaux sont source de nombreux stress conduisant à un affaiblissement du système immunitaire. L’efficacité de ce système repose notamment sur la diversité des répertoires de récepteurs aux antigènes présents à la surface des lymphocytes B (BCR) et T (TCR) permettant de reconnaitre un grand nombre d’antigènes différents. Au cours de cette thèse, j’ai étudié la diversité des récepteurs à l’antigène dans trois modèles animaux différents : l’amphibien Pleurodeles waltl, le modèle murin de suspension anti‐orthostatique (micropesanteur simulée) et le modèle murin CUMS (pour « Chronic Unpredictable Mild Socio‐environmental stressors ») qui fait appel à des stress sociaux et environnementaux chroniques similaires à ceux rencontrés lors des vols spatiaux. L’étude des répertoires de chaînes lourdes d’anticorps IgM et IgY de P. waltl a montré que ceux‐ci présentent une diversité importante, faisant de cet animal un bon modèle pour étudier les effets d’un vol spatial sur le système immunitaire humoral. Nous avons aussi montré que l’exposition à la suspension anti‐orthostatique durant 21 jours diminue la lymphopoïèse B mais n’affecte que modérément la diversité du répertoire de chaînes lourdes d’IgM. Ces résultats ont été comparés à ceux obtenus avec des souris âgées afin de savoir si la suspension anti‐orthostatique induit un vieillissement accéléré du système immunitaire. Même si nous avons noté des similitudes intéressantes entre ces deux groupes de souris, nous avons constaté que l’effet du vieillissement sur le répertoire d’IgM est plus important que celui de la suspension anti‐orthostatique, suggérant que le temps d’exposition au modèle anti‐orthostatique devrait être augmenté pour accentuer ses effets sur le répertoire d’anticorps. Quant au modèle CUMS, nous avons montré que son application durant la gestation n’impacte pas la lymphopoïèse T chez les souriceaux nouveau‐nés mais affecte 25% de leur répertoire de chaînes lourdes β du TCR. Ces résultats suggèrent que des stress socio‐environnementaux chroniques, même de faibles intensités, pourraient modifier les capacités de reconnaissance antigénique de l’hôte / Spaceflight is a source of various stresses leading to the weakening of the immune system. The efficiency of this system relies, notably, on the diversity of antigen receptor repertoires present on B (BCR) and T (TCR) cells, allowing the recognition of a vast array of antigens. During this thesis, I studied the diversity of antigen receptors in three different animal models: the amphibian Pleurodeles waltl, the murine anti‐orthostatic suspension model (simulated microgravity) and the CUMS (for "Chronic Unpredictable Mild Socio‐environmental stressors") murine model involving exposure to chronic social and environmental stressors similar to those encountered during spaceflights. Analyses of P. waltl IgM and IgY heavy chain repertoires have shown that they are highly diverse, making this species a nice animal model for studying the effects of spaceflight on the humoral immune system. We have also shown that 21 days of anti‐orthostatic suspension decrease murine B lymphopoiesis and moderately affect IgM heavy chain repertoire diversity. These results were compared with those obtained with old mice to determine if anti‐orthostatic suspension induces an accelerated aging of the immune system. Although we noted interesting similarities between these two groups of mice, we found that the effect of aging on IgM repertoire is stronger than that of the anti‐orthostatic suspension, suggesting that anti‐orthostatic duration should be extended to increase the effects of this model on antibody repertoire. Finally, regarding the CUMS model, we have shown that, when applied during gestation it does not affect T lymphopoiesis in newborn mice but affects 25% of their TCRβ heavy chain repertoire. These results suggest that low‐intensity chronic socio‐environmental stressors may alter antigen recognition capabilities of the host

The architecture of a system which enables the cost-effective exploration of the solar system is proposed. Such a system will make use of the benefits of the natural dynamics represented in the Circular Restricted Three-Body Problem (CRTBP). Additionally, a case study of the first missions which apply the lessons from the CRTBP is examined. The guiding principle of the proposed system is to apply lessons learned from both the Apollo project for deep space exploration and the International Space Station for long term habitation in space as well as modular space vehicle design. From this preliminary system design, a number of missions are outlined. These missions form the basis of an evolvable roadmap to fully develop the infrastructure required for long-term sustained manned exploration of the solar system. This roadmap provides a clear and concise pathway from current exploration capabilities to the current long-term goal of sustained manned exploration of Mars. The primary method employed in designing the staging orbits is the "Single Lunar Swingby", each of the component segment trajectory design processes is explored in detail. Additionally, the method of combining each of these segments together in a larger End-to-End optimizer environment within the General Mission Analysis Tool (GMAT) is introduced, called the Multiple Shooting Method. In particular, a specific Baseline Parking Orbit, or BPO, is chosen and analyzed. This BPO serves as the parking home orbit of any assets not currently in use. A BPO of amplitude (14000, 28000, 6000) kilometers. The BPO has full coverage to both the Earth and the Moon and orbit station-keeping may be conducted at a cost of less than 1 m/s over a 14 year period. This provides a cost-effective platform from which more advanced exploration activities can be based, both robotic and manned. One of the key advanced exploration activities considered is manned exploration of Mars, one of the current long-term goals of NASA. Trajectories from the BPO to Mars and back to Earth are explored and show approximately 50% decrease in required ΔV provided by the spacecraft.

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