The role of the space industry in building capacity in emerging space nations

The space industry in established space-faring nations is playing an increasingly important role in the development of capacity in emerging space nations. The role of industry ranges from provision of turn-key systems, to provision of training and joint development of satellites in partnership with emerging space countries. Ranked number 1 worldwide in terms of satellites ordered in 2006, Thales Alenia Space is at the heart of the most high performance satellite technologies in both civil and defense sectors. The company has been involved in parterships with a number of emerging space nations. This paper discusses several key factors for successful interaction of industry with national space programmes in emerging space nations.     

Different space weather effects in anomalies of the high and low orbital satellites

Preliminary results of the EU INTAS Project 00810, which aims to improve the methods of safeguarding satellites in the Earth’s magnetosphere from the negative effects of the space environment, are presented. Anomaly data from the “Kosmos” series satellites in the period 1971–1999 are combined in one database, together with similar information on other spacecraft. This database contains, beyond the anomaly information, various characteristics of the space weather: geomagnetic activity indices (Ap, AE and Dst), fluxes and fluences of electrons and protons at different energies, high energy cosmic ray variations and other solar, interplanetary and solar wind data. A comparative analysis of the distribution of each of these parameters relative to satellite anomalies was carried out for the total number of anomalies (about 6000 events), and separately for high (5000 events) and low (about 800 events) altitude orbit satellites. No relation was found between low and high altitude satellite anomalies. Daily numbers of satellite anomalies, averaged by a superposed epoch method around sudden storm commencements and proton event onsets for high (>1500 km) and low (<1500 km) altitude orbits revealed a big difference in a behavior. Satellites were divided on several groups according to the orbital characteristics (altitude and inclination). The relation of satellite anomalies to the environmental parameters was found to be different for various orbits that should be taken into account under developing of the anomaly frequency models.     

Two-dimensional phase plane structure and the stability of the orbital motion for space debris in the geosynchronous ring

Based on the orbital resonance model, we study the two-dimensional phase plane structure of the motion of space debris orbiting the geosynchronous ring under the combined effects of the tesseral harmonics J₂₂, J₃₁ and J₃₃ of the Earth’s gravitational field. We present the main characteristic parameters of the two-dimensional phase plane structure. We also analyze the stability of the two-dimensional phase plane structure with numerical method. Our main findings indicate that the combined effects of the tesseral harmonics J₂₂, J₃₁ and J₃₃ fully determine the two-dimensional phase plane structure of the space debris, and it remains robust under the effect of the Earth’s actual gravitational field, the luni-solar perturbations and the solar radiation pressure with the normal area-to-mass ratios.     

A review of instruments and methods for dosimetry in space

Instruments and methods recently used for space radiation dosimetry are reviewed for the purposes of comparison and reference. Passive detection methods mentioned include track-etch, luminescent, nuclear emulsion, and metal foil detectors. These can provide a reliable source of data for all types of radiation, but often require processing that cannot occur in space. Experimental methods of LET determination using TLDs, such as the high temperature peak ratio (HTR) method, are also discussed. Portable readout passive detectors including Pille, MOSFET, and bubble detector systems provide a novel alternative to traditional passive detectors, but research is more limited and their widespread use has yet to be established. Active detectors including DOSTEL, CPDS, RRMD-III, TEPC, R-16, BBND, and the Liulin series are examined for technical details. These instruments allow the determination of dose in real-time, and some can determine LET of incident particles by measuring energy deposition over a known path-length, but size and power consumption limit their practical use for dosimetry. Improved neutron dosimetry and development of a small active or portable readout personnel dosimeter capable of accurate LET determination are important steps for managing the effects of long-term exposure to the space radiation environment.     

Development of a thin section device for space exploration: Overview and system performance estimates

In this paper we present a conceptual design of a spaceborne instrument for the in situ production of rock thin sections on planetary surfaces. The in situ Automated Rock Thin Section Instrument (IS-ARTS) conceptual design demonstrates that the in situ production of thin sections on a planetary body is a plausible new instrument capability for future planetary exploration. Thin section analysis would reduce much ambiguity in the geological history of a sampled site that is present with instruments currently flown. The technical challenge of producing a thin section device compatible with the spacecraft environment is formidable and has been thought too technically difficult to be practical. Terrestrial thin section preparation requires a skilled petrographist, several preparation instruments that individually exceed typical spacecraft mass and power limits, and consumable materials that are not easily compatible with spaceflight. In two companion papers we present research and development work used to constrain the capabilities of IS-ARTS in the technical space compatible with the spacecraft environment. For the design configuration shown we conclude that a device can be constructed that is capable of 50 sample preparations over a 2 year lifespan with mass, power, and volume constraints compatible with current landed Mars mission configurations. The technical requirements of IS-ARTS (mass, power and number of samples produced) depend strongly on the sample mechanical properties, sample processing rate, the sample size and number of samples to be produced.     

Using parallel computing for the display and simulation of the space debris environment

Parallelism is becoming the leading paradigm in today’s computer architectures. In order to take full advantage of this development, new algorithms have to be specifically designed for parallel execution while many old ones have to be upgraded accordingly. One field in which parallel computing has been firmly established for many years is computer graphics. Calculating and displaying three-dimensional computer generated imagery in real time requires complex numerical operations to be performed at high speed on a large number of objects. Since most of these objects can be processed independently, parallel computing is applicable in this field. Modern graphics processing units (GPUs) have become capable of performing millions of matrix and vector operations per second on multiple objects simultaneously.     

Validation of the in-flight calibration procedures for the MICROSCOPE space mission

The MICROSCOPE space mission aims to test the Equivalence Principle with an accuracy of 10^-15${10}^{-15}$. The drag-free micro-satellite will orbit around the Earth and embark a differential electrostatic accelerometer including two cylindrical test masses submitted to the same gravitational field and made of different materials. The experience consists in testing the equality of the electrostatic acceleration applied to the masses to maintain them relatively motionless. The accuracy of the measurements exploited for the test of the Equivalence Principle is limited by our a priori knowledge of several physical parameters of the instrument. These parameters are partially estimated on-ground, but with an insufficient accuracy, and an in-orbit calibration is therefore required to correct the measurements. The calibration procedures have been defined and their analytical performances have been evaluated. In addition, a simulator software including the dynamics model of the instrument, the satellite drag-free system and the perturbing environment has been developed to numerically validate the analytical results. After an overall presentation of the MICROSCOPE mission, this paper will describe the calibration procedures and focus on the simulator. Such an in-flight calibration is mandatory for similar space missions taking advantage of a drag-free system.     

A new algorithm for optical observations of space debris with the TAROT telescopes

Since 2004, we observe satellites in the geostationary orbit with a network of robotic ground based fully automated telescopes called TAROT. One of them is located in France and the second at ESO, La Silla, Chile. The system processes the data in real time. Its wide field of view is useful for the discovery, the systematic survey and for the tracking of both catalogued and un-catalogued objects. We present a new source extraction algorithm based on morphological mathematic, which has been tested and is currently under implementation in the standard pipeline. Using this method, the observation strategy will correlate the measurements of the same object on successive images and give better detection rate and false alarm rate than the previous one. The overall efficiency and quality of the survey of the geostationary orbit has drastically improved and we can now detect satellites and debris in different orbits like Geostationary Transfer Orbit (GTO). Results obtained in real conditions with TAROT are presented.     

The extension of the INCL model for simulation of shielding in space

Radiation hazard for space missions is mainly due to cosmic ray protons, helium nuclei and light ions, whose energy spectrum is maximum around 1 GeV per nucleon but remains non-negligible for energies up to 15 GeV per nucleon. Nuclear reactions induced by high energy protons are often described by intranuclear cascade plus evaporation models. The attention is focused here on the Liège Intranuclear Cascade model (INCL), which has been shown to reproduce fairly well a great deal of experimental data for nucleon-induced reactions in the 200 MeV to 2 GeV range, when coupled with the ABLA evaporation-fission code. In order to extend the model to other conditions relevant for space radiation, three improvements of INCL are under development. They are reported on here. First, the reaction model has been extended to nucleon–nucleus reactions at incident energies up to 15 GeV, mainly by the inclusion of additional pion production channels in nucleon–nucleon collisions during the cascade. Second, a coalescence mechanism for the emission of light charged particles has been implemented recently. Finally, the model has been modified in order to accommodate light ions as projectiles. First results are shown and compared with illustrative experimental data. Implications for issues concerning radiation protection in space are discussed.     

On the practical exploitation of perturbative effects in low Earth orbit for space debris mitigation

This paper presents the results of a numerical evaluation of the natural lifetime reduction in low Earth orbit, due to dynamical perturbations. The study considers two values for the area-to-mass ratio, a nominal ratio which resembles a typical value of spacecraft in orbit today, and an enhanced ratio which covers the surface augmentation. The results were obtained with two orbit propagators, one of a semi-analytical nature and the second one using non-averaged equations of motion. The simulations for both propagators were set up similarly to allow comparison. They both use the solar radiation pressure and the secular terms of the geopotential ($J_2,J_4$ and $J_6$). The atmospheric drag was turned on and off in both propagators to alternatively study the eccentricity build up and the residual lifetime. The non-averaging case also covers a validation with the full 6?×?6 geopotential. The results confirm the findings in previous publications, that is, the possibility for de-orbiting from altitudes above the residual atmosphere if a solar sail is deployed at the end-of-life, due to the combined effect of solar radiation pressure and the oblateness of the Earth. At near polar inclinations, shadowing effects can be exploited to the same end. The results obtained with the full, non-averaging propagator revealed additional de-orbiting corridors associated with solar radiation pressure which were not found by previous work on space debris mitigation. The results of both tools are compared for specific initial conditions. For nominal values of area-to-mass ratio, instead, it is confirmed that this resonance effect is negligible.The paper then puts the findings in the perspective of the current satellite catalogue. It identifies space missions which are currently close to a resonance corridor and shows the orbit evolution within the resonances with a significantly shorter residual orbital lifetime. The paper finishes with a discussion on the exploitation of these effects with regards to the long-term simulation of the space debris environment and a flux and collision probability comparison.     

The bistatic radar capabilities of the Medicina radiotelescopes in space debris detection and tracking

An accurate measurement of the position and trajectory of the space debris fragments is of primary importance for the characterization of the orbital debris environment. The Medicina Radioastronomical Station is a radio observation facility that is here proposed as receiving part of a ground-based space surveillance system for detecting and tracking space debris at different orbital regions (from Low Earth Orbits up to Geostationary Earth Orbits). The proposed system consists of two bistatic radars formed by the existing Medicina receiving antennas coupled with appropriate transmitters. This paper focuses on the current features and future technical development of the receiving part of the observational setup. Outlines of possible transmitting systems will also be given together with the evaluation of the observation strategies achievable with the proposed facilities.     

On the detection of anomalous seismo-ionospheric behavior in the presence of space weather stimuli for large earthquakes

Anomalous behavior of ionospheric total electron content (TEC) prior to earthquake has been observed in many studies. Evidence of such seismo-ionospheric coupling effects suggests that it is plausible to rely on TEC signatures for early earthquake warning. However, the detection of pre-earthquake TEC anomalies (PETA) has not been adopted in practice due to two pertinent issues. Firstly, the effects of space weather activity can affect TEC levels and cause anomalous behavior in the TEC. Usually arbitrary thresholds are set for space weather indices to eliminate TEC anomaly due to space weather effects. Secondly, the choice regarding moving time-window length used to characterise background variation of TEC within the statistical envelope approach has an effect on detection of PETA. While the rule-of-thumb in selecting the moving window length is to have a time window capable of capturing background variability and short-term fluctuations, the length of the time window used in the literature varies with little justification. In this study, a critical examination is conducted on the statistical envelope approach and in particular, to eliminate the effect of space weather activity without the use of arbitrary space indices to detect PETA. A two-part PETA identification procedure is proposed, consisting of wavelet analyses isolating non-earthquake TEC contributions, followed by the statistical envelope method using a moving window length standardized based on observed periodicities and statistical implications is suggested. The approach is tested on a database of 30 large earthquakes (M?≥?7.0). The proposed procedure shows that PETA can be detected prior to earthquakes at higher confidence levels without the need to separately check for space weather activity. More importantly, the procedure was able to detect PETA for studies where it was previously reported that PETA could not be detected or detected convincingly.     

Preliminary results of space experiment: Implications for the effects of space radiation and microgravity on survival and mutation induction in human cells

In view of the concern for the health of astronauts that may one day journey to Mars or the Moon, we investigated the effect that space radiation and microgravity might have on DNA damage and repair. We sent frozen human lymphoblastoid TK6 cells to the International Space Station where they were maintained under frozen conditions during a 134-day mission (14 November 2008 to 28 March 2009) except for an incubation period of 8 days under 1G or μG conditions in a CO₂ incubator. The incubation period started after 100 days during which the cells had been exposed to 54 mSv of space radiation. The incubated cells were then refrozen, returned to Earth, and compared to ground control samples for the determination of the influence of microgravity on cell survival and mutation induction. The results for both varied from experiment to experiment, yielding a large SD, but the μG sample results differed significantly from the 1G sample results for each of 2 experiments, with the mean ratio of μG to 1G being 0.55 for the concentration of viable cells and 0.59 for the fraction of thymidine kinase deficient (TK⁻) mutants. Among the mutants, non-loss of zygosity events (point mutations) were less frequent (31%) after μG incubation than after 1G incubation, which might be explained by the influence of μG on cellular metabolic or physiological function. Additional experiments are needed to clarify the effect of μG interferes on DNA repair.     

Verification of shielding effect by the water-filled materials for space radiation in the International Space Station using passive dosimeters

The dose reduction effects for space radiation by installation of water shielding material (“protective curtain”) of a stack board consisting of the hygienic wipes and towels have been experimentally evaluated in the International Space Station by using passive dosimeters. The averaged water thickness of the protective curtain was 6.3 g/cm². The passive dosimeters consisted of a combination of thermoluminescent detectors (TLDs) and plastic nuclear track detectors (PNTDs). Totally 12 passive dosimeter packages were installed in the Russian Service Module during late 2010. Half of the packages were located at the protective curtain surface and the other half were at the crew cabin wall behind or aside the protective curtain. The mean absorbed dose and dose equivalent rates are measured to be 327 μGy/day and 821 μSv/day for the unprotected packages and 224 μGy/day and 575 μSv/day for the protected packages, respectively. The observed dose reduction rate with protective curtain was found to be 37 ± 7% in dose equivalent, which was consistent with the calculation in the spherical water phantom by PHITS. The contributions due to low and high LET particles were found to be comparable in observed dose reduction rate. The protective curtain would be effective shielding material for not only trapped particles (several 10 MeV) but also for low energy galactic cosmic rays (several 100 MeV/n). The properly utilized protective curtain will effectively reduce the radiation dose for crew living in space station and prolong long-term mission in the future.     

The effect of the space flight environment on mucin production in the mouse uterine tube

Numerous studies have indicated that the microgravity environment of space has harmful effects on several tissues throughout the body. Although this phenomenon is well documented, research in this area is still in its relative infancy. This study investigates the effects of space flight on mucin production of the uterine tubes of mice. This study examined the epithelium of the uterine tubes from female mice that were flown on the space shuttle Endeavour for 13 days in August, 2007 and their concomitant controls. The tissue was qualitatively analyzed for the type of mucin produced, i.e., acidic, neutral, acidic/neutral mixture. Further, the tissue was quantitatively analyzed for the amounts of mucins produced by measuring the thickness of the mucin layer for each region of the uterine tube: isthmus, ampulla, and infundibulum. One way ANOVA tests were used to compare mucin thickness between all three sets of animals. Results indicate similar but not identical results between the three regions of the uterine tube. The Baseline tissue had the thickest mucin layer regardless of treatment group. In the ampulla the mucin layer was the thinnest in the Flight tissue, followed by the Ground Control, with the Baseline being the thickest. Analysis of the mucin layer of the infundibulum of the three treatment groups indicated no difference in its thickness between the three regions of the uterine tube. These results indicate a trend toward thinning of the mucin layer of the uterine tube in space flight, but also indicate an influence by the housing environment.     

On the application of Exploratory Data Analysis for characterization of space weather data sets

This paper presents an overview of the mathematical foundations for techniques in Exploratory Data Analysis (EDA) for the purpose of investigating the relationships among the numerous variables in large sets of multivariate space weather data. Specifically, we cover techniques in Principal Components Analysis (PCA) and Common Factor Analysis (CFA). These techniques are illustrated using space weather activity indices collected during the year 2002 and the corresponding noon-time hmF2 data from the International Reference Ionosphere (IRI). A CFA is used to categorize the activity indices, and a PCA is used to derive two macro-indices of activity to ascertain the strength of solar and geomagnetic activity. These macro-indices are then used to compare and contrast IRI’s noon-time hmF2 values at six different geographic stations. It was found that the correlation between hmF2 and the macro-indices more accurately represented the variation of this correlation with latitude found in previous studies than if we used an isolated conventional index, such as SSN and AE. We also found that the daily maximum value of the Polar Cap Index was dependent on both solar and geomagnetic activity, but the closely-related cross-Polar Cap Potential was solely associated with elevated levels of geomagnetic activity, which is a unique result compared to previous studies. We argue that the discrepancy can be explained by the difference in experiment designs between the two studies. This paper demonstrates the usefulness of EDA in space weather studies of large multivariate data sets.     

Cowpeas and pinto beans: Performance and yields of candidate space crops in the laboratory biosphere closed ecological system

An experiment utilizing cowpeas (Vigna unguiculata L.), pinto beans (Phaseolus vulgaris L.) and Apogee ultra-dwarf wheat (Triticum sativa L.) was conducted in the soil-based closed ecological facility, Laboratory Biosphere, from February to May 2005. The lighting regime was 13 h light/11 h dark at a light intensity of 960 μmol m⁻² s⁻¹, 45 mol m⁻² day⁻¹ supplied by high-pressure sodium lamps. The pinto beans and cowpeas were grown at two different planting densities. Pinto bean production was 341.5 g dry seed m⁻² (5.42 g m⁻² day⁻¹) and 579.5 dry seed m⁻² (9.20 g m⁻² day⁻¹) at planted densities of 32.5 plants m⁻² and 37.5 plants m⁻², respectively. Cowpea yielded 187.9 g dry seed m⁻² (2.21 g m⁻² day⁻¹) and 348.8 dry seed m⁻² (4.10 g m⁻² day⁻¹) at planted densities of 20.8 plants m⁻² and 27.7 plants m⁻², respectively. The crop was grown at elevated atmospheric carbon dioxide levels, with levels ranging from 300–3000 ppm daily during the majority of the crop cycle. During early stages (first 10 days) of the crop, CO₂ was allowed to rise to 7860 ppm while soil respiration dominated, and then was brought down by plant photosynthesis. CO₂ was injected 27 times during days 29–71 to replenish CO₂ used by the crop during photosynthesis. Temperature regime was 24–28 °C day/deg 20–24 °C night. Pinto bean matured and was harvested 20 days earlier than is typical for this variety, while the cowpea, which had trouble establishing, took 25 days more for harvest than typical for this variety. Productivity and atmospheric dynamic results of these studies contribute toward the design of an envisioned ground-based test bed prototype Mars base.     

VHF radio response of the near Earth space during solar activity growth in October, 2003

The analysis of observations of very high frequency radio noise intensity at the middle latitude on a frequency f = 500 MHz from 14th till 26th of October, 2003 is presented. These data are compared with the solar radio bursts in the range of frequencies 1–14 MHz registered by RAD2 receiver of the WAVES device installed on board the WIND spacecraft.     

Silkworms culture as a source of protein for humans in space

This paper focuses on the problem about a configuration with complete nutrition for humans in a Controlled Ecological Life Support System (CELSS) applied in the spacebases. The possibility of feeding silkworms to provide edible animal protein with high quality for taikonauts during long-term spaceflights and lunar-based missions was investigated from several aspects, including the nutrition structure of silkworms, feeding method, processing methods, feeding equipment, growing conditions and the influences on the space environmental condition changes caused by the silkworms. The originally inedible silk is also regarded as a protein source. A possible process of edible silk protein was brought forward in this paper. After being processed, the silk can be converted to edible protein for humans. The conclusion provides a promising approach to solving the protein supply problem for the taikonauts living in space during an extended exploration period.