MarcoPolo-R: Near-Earth Asteroid sample return mission selected for the assessment study phase of the ESA program cosmic vision

This paper presents the sample return mission to a primitive Near-Earth Asteroid (NEA) MarcoPolo-R proposed to the European Space Agency in December 2010. MarcoPolo-R was selected in February 2011 with three other missions addressing different science objectives for the two-year Assessment Phase of the Medium-Class mission competition of the Cosmic Vision 2 program for launch in 2022. The baseline target of MarcoPolo-R is the binary NEA (175706) 1996 FG3, which offers an efficient operational and technical mission profile. A binary target also provides enhanced science return. The choice of a binary target allows several scientific investigations to occur more easily than through a single object, in particular regarding the fascinating geology and geophysics of asteroids. MarcoPolo-R will rendezvous with a primitive, organic-rich NEA, scientifically characterize it at multiple scales, and return a bulk sample to Earth for laboratory analyses. The MarcoPolo-R sample will provide a representative sample from the surface of a known asteroid with known geologic context, and will contribute to the inventory of primitive material that is probably missing from the meteorite collection. The MarcoPolo-R samples will thus contribute to the exploration of the origin of planetary materials and initial stages of habitable planet formation, to the identification and characterization of the organics and volatiles in a primitive asteroid and to the understanding of the unique geomorphology, dynamics and evolution of a binary asteroid that belongs to the Potentially Hazardous Asteroid (PHA) population.     

Emerging views on a joint Soviet—US Mars mission

The political climate today is more favourable for joint superpower cooperation in space than it has been for many years. The authors of this Viewpoint, who studied together as members of the inaugural class of the International Space University, trace recent developments in the USA and USSR and evaluate how they might affect cooperation. Ironically, they find, it is the common problems both nations face in relation to space activities - budgetary constraints and declining political support for their space programmes - that argue most forcefully for cooperation. But a subtle and initially modest strategy will be needed to overcome the obstacles that stand in the way.     

SPS — time for a pilot plant

Scientists have expended much energy researching SPS but their theories have never yet been realistically tested. It is time for this to change and SPS 2000 — a Japanese-sponsored project to construct and operate a pilot plant to supply electricity to residents of equatorial zones — could provide the means. The project and its benefits are described and the political—economic imperatives for undertaking it presented. The author argues that there are cogent — and practical — reasons for funding a pilot plant, especially given the vast sums spent on other space activities, and on nuclear power, although the latter has never lived up to expectations.     

Options for space — proposal for a programme

Because of the physical scale of human operations at present, we need to extend them into the Solar System for sustainability and into interstellar space for knowledge. Stabilizing the population on Earth, as well as reducing poverty, is vital, as is a more environmentally appropriate demographic transition than the historical one. Space assets can contribute most to strategic threats in areas like power and minerals and can also assist global education. Such public interest is important as education, but it is vital to remember that a certain level of precision in materials and engineering is needed before ideas become realizable. The crucial step is to turn the space environment to an open market and override the present government monopoly constraint. As a start, a Center for International Space Industrialization Research (CSIR) is to be set up as a model for the better understanding of the issues involved, thus making a case for strategic investment for space assets.     

The data compression problem for the “GAIA” astrometric satellite of ESA

Space-based astrometry has a great tradition at ESA. The first space-based astrometric satellite in history, “Hipparcos”, was launched by ESA in 1989 and, in spite of orbital problems, was able to accomplish almost all of its tasks until it was finally shut down in 1993. The results of the Hipparcos mission were published by ESA in 1997 in the form of six CD-ROMs: the Hipparcos Catalogue contains 118,218 entries with median astrometric precision of around 1 milliarcsec, and specific results for double and multiple systems. In practice, Hipparcos drew for the first time the three-dimensional “map” of the spherical region of the Galaxy surrounding the Sun and having a radius of roughly 1,000 light years.

Then, in 1995, ESA launched the study of a new astrometric satellite, named “GAIA” and about a hundred times more powerful than Hipparcos, i.e. with median astrometric precision of around 10 microarcsec. This new satellite is intended to measure the parallaxes of over 50 million stars in the Galaxy, at least for the brightest stars, and this would mean to “draw” the three-dimensional map of the whole Galaxy, reaching out even to the Magellanic Clouds, 180,000 light years away.

The team of European scientists and engineers now designing GAIA, however, is facing hard technological difficulties. One of these is the design and coding of radically new and ultra-powerful mathematical algorithms for the on-board compression of the 50-million-stars data that GAIA will send to Earth from its intended geostationary orbit. Preliminary estimates of the raw data rates from the GAIA focal plane, in fact, are of the order of a few Gigabits per second. To reduce the data stream to the envisaged telemetry link of 1 Megabit per second, on-board data compression with a 1 to 1,000 ratio is the target. Clearly, this is far beyond the capabilities of any lossless compression technique (enabling compression ratios of 1 to some tens), and so some “wise” lossy compression mathematical procedure must be adopted.

In this paper a GAIA-adapted lossy data compression technique is presented, based on the Karhunen-Loève Transform (KLT). The essence of this method was already used by NASA for the Galileo mission when the large antenna got stuck and the mission was rescued by re-programming the on-board computer in terms of the KLT. That transform was officially named ICT — “Integer Cosine Transform” — by the NASA-JPL team led by Dr. Kahr-Ming Cheung. But the KLT here described for GAIA will of course differ from the JPL one in many regards, owing to the advances in computer technology.

Finally, estimates are also given about the possibility of using the KLT for onboard data compression in case GAIA is going to be put into orbit around the Lagrangian point L2 of the Earth-Sun system, and, above all, in case the number of stars to be observed is actually raised from 50 millions to one billion, as ESA currently appears to be likely to pursue.     

The ISMA proposal — time for a reappraisal?

The proposal for an International Satellite Monitoring Agency (ISMA) was made by France in 1978. This article looks at the arguments raised against developing an ISMA and reassesses the proposal in the light of current and anticipated developments in the field of verification, and new national space programmes.     

Space education policy — a global imperative

The discoveries and knowledge gained from space exploration and technology development are valuable scientific education tools which are not being adequately used in the classroom. Moreover, the increasing application of space technology to everyday life and industry requires a work force educated to be able to work productively in this field and to take advantage of all it has to offer. This article provides a survey of what is presently being done in the field of space education in Europe and the USA. Although encouraging, it is not nearly enough to meet the needs of 21st century society, principally because current efforts lack government or industry support. The author argues that this state of affairs must change, and proposed an international symposium as a first step towards this goal.     

UK space policy — a problem of culture

According to the UK government, the announcement in July 1987 of a freeze on the British National Space Centre's (BNSC) budget was based solely on lack of money and the belief that private industry, rather than the state, should fund space activities. In challenging the validity of this view, the author suggests that it has also been used to conceal internal bureaucratic competition and a myopic, market-driven mind-set.     

Space station — the new frontier

The exciting challenge of building a permanent space station has been taken up by the USA, and participation in its development has been offered to the USA's allies. European countries are faced with the dilemma of whether to cooperate or to try to develop an autonomous approach. This article discusses the opportunities for Europe in participating closely in the US project — particularly in providing pressurized modules based on the Columbus programme — and argues that it is an opportunity not to be missed.     

Military computing — the last generation

This article examines the computing requirements of the Strategic Defense Initiative. Dr Din points to the massive software problems inherent in SDI programming requirements, and raises the crucial issue of the potential bypassing of human control in any actual outbreak of hostilities.     

Commercialization of space — the investment opportunities

This report by Ray Williamson of the US Office of Technology Assessment, looks at the prospects for commercialization of space into the 21st century and discusses the relative benefits of private v government investment. The report is taken from a revised version of an article originally appearing in the October 1982 issue of Futures. A fully updated paper will appear in Michiel Schwarz and Paul Stares (eds), ‘The Exploitation of Space: Policy Trends in the Military and Commercial Uses of Space’ (Butterworths, Guildford, UK, 1985).     

Hyperspectral imaging—An advanced instrument concept for the EnMAP mission (Environmental Mapping and Analysis Programme)

In the upcoming generation of satellite sensors, hyperspectral instruments will play a significant role. This payload type is considered world-wide within different future planning.Our team has now successfully finalized the Phase B study for the advanced hyperspectral mission EnMAP (Environmental Mapping and Analysis Programme), Germans next optical satellite being scheduled for launch in 2012. GFZ in Potsdam has the scientific lead on EnMAP, Kayser-Threde in Munich is the industrial prime.The EnMAP instrument provides over 240 continuous spectral bands in the wavelength range between 420 and 2450 nm with a ground resolution of 30 m×30 m. Thus, the broad science and application community can draw from an extensive and highly resolved pool of information supporting the modeling and optimization process on their results. The performance of the hyperspectral instrument allows for a detailed monitoring, characterization and parameter extraction of rock/soil targets, vegetation, and inland and coastal waters on a global scale supporting a wide variety of applications in agriculture, forestry, water management and geology. The operation of an airborne system (ARES) as an element in the HGF hyperspectral network and the ongoing evolution concerning data handling and extraction procedures, will support the later inclusion process of EnMAP into the growing scientist and user communities.     

Buying Russian technology — pros and cons for the US programme

A marriage between Russian space technology and US space ambitions was unthinkable only a short time ago, but that potential union is now the talk of the town. With the dizzying pace of changes in US-Russian relationships, what is written here in July 1992 may well have changed by the time this article is published. Nevertheless, a glance at what the Russians are selling, what the USA may want to buy and the major policy issues involved is worth a look. Traditional cooperative ventures remain an important part of US-Russian space relations, but are not the focus of this article.     

Flexbus — an attractive technical solution for small missions

Responding to the demand for a ‘faster, cheaper, better’ implementation of space related services, Domier Satellitensysteme GmbH has established and exercised an approach for the development and production of satellites and the corresponding ground equipment for small missions, referred to as Flexbus. It allows to support space service customers starting from mission engineering via design, development and manufacturing of the necessary hardware, the launch service and ending with the hand-over of the operational system. Flexbus harmonises a modular component concept with a sound design and development approach, as a whole providing the means to offer high quality products in a fairly short time and for competitive pricing. This paper will outline the major features of the Flexbus approach and describe application examples.     

CEOS — an example of fruitful international cooperation

This paper reviews the evolution of CEOS (Committee on Earth Observations Satellites) from the early days, where participating agencies were primarily concerned with compatibility issues and space programs were chiefly technology-driven, up to the present, where complementarity of satellite programs and fulfillment of final user needs are the main goals being pursued.It also analyzes the favorable conditions that allowed continuity and evolution of the efforts carried by the Committee, in both the technical and the administrative areas, and granted the results achieved so far.Finally, it addresses the expectations of the Committee about the cooperation and interaction with other international bodies, with national governments and with the private sector, with the final aim of maximizing the benefits that Earth Observations can provide for Science and for the well-being of humanity, in particular the people of less-favored regions of the earth.     

Dominance in space — a new means of exercising global power?

Sustained criticism of the strategy of nuclear deterrence and technological developments in the military uses of space suggest that nuclear weapons may soon be replaced by control of outer space as the USA and USSR's primary instrument of global power. This article traces the change in perceptions of nuclear weapons policy and assesses the potential of outer space as a means of control, and the plans of the two superpowers for its exploitation, especially in the military sphere. The consequences for Western Europe of a shift from nuclear to space-based weapons as the primary guarantor of national security are also discussed.     

Results of impact simulation for the GIOTTO mission

The European Space Agency (ESA) has decided to carry out a fly-by mission to the comet Halley. The spacecraft will be launched by an ARIANE II and intercept the retrograde Halley orbit on 13 March, 1986. One group of experiments is designed to obtain data on size, mass and composition of the dust in the cometary tail. Because of the very high relative velocity during fly-by (69 km/s) laboratory experiments are necessary to develop and calibrate the experiments. These experiments are presently under way in the laboratory of the Lehrstuhl für Raumfahrttechnik of the Technische Universität München. First results have been obtained for both the Dust Impact Detection System (DIDSY) and the P?articulate Impact Analyzer (PIA). These results are compared with the theoretical models for hypervelocity impact craters. The agreement is good at impact velocities around 15 km/s.     

One optimization problem for trajectories of spacecraft rendezvous mission to a group of asteroids

The optimization problem is considered for the trajectory of a spacecraft mission to a group of asteroids. The ratio of the final spacecraft mass to the flight time is maximized. The spacecraft is controlled by changing the value and direction of the jet engine thrust (small thrust). The motion of the Earth, asteroids, and the spacecraft proceeds in the central Newtonian gravitational field of the Sun. The Earth and asteroids are considered as point objects moving in preset elliptical orbits. The spacecraft departure from the Earth is considered in the context of the method of a point-like sphere of action, and the excess of hyperbolic velocity is limited. It is required sequentially to have a rendezvous with asteroids from four various groups, one from each group; it is necessary to be on the first three asteroids for no less than 90 days. The trajectory is finished by arrival at the last asteroid. Constraints on the time of departure from the Earth, flight duration, and final mass are taken into account in this problem.     

The challenges and opportunities of a commercial human spaceflight mission to the ISS

ESA astronauts' ISS flight opportunities are considered as a vital source to meet the utilisation, operation and political objectives that Europe has established for participating in the International Space Station programme. Recent internal ESA assessments have demonstrated that a rate of three flights per year for European Astronauts should be maintained as a minimum objective. The current flight rate is lower than this. In order to improve this situation, in the context of the activation of the ESA ISS Commercialisation programme, ESA is developing the conditions for the establishment of commercially based human spaceflights with the financial support of both ESA and the private sector or, in the future, only the latter. ESA is working in a Partnership with the space industry to facilitate the implementation of such projects and support customers with a range of end-to-end commercial services. The opportunities and challenges of a "commercial human spaceflight", involving a member of the European Astronaut Corps, or a privately employed flight participant, are discussed here.     

Effects of HZE particle on the nigrostriatal dopaminergic system in a future Mars mission

Because of long duration travel outside the Earth's magnetic field, the effect of iron-rich high charge and energy (HZE) particles in Galactic Cosmic Rays on human body is the major concern in radiation protection. Recently attention has been directed to effects on the central nervous system in addition to mutagenic effects. In particular, a reduction in striatal dopamine content on nigrostriatal dopaminergic system has been reported by investigators using accelerated iron ions in ground-based mammalian studies. In addition, studies of the pathophysiology of Parkinson's disease demonstrated that excess iron cause a reduction in the dopamine content in the substantia nigra. This suggests an intriguing possibility to explain the selective detrimental effects of HZE particles on the dopaminergic system. Should these particles have biochemical effects, possible options for countermeasures are: (1) nutritional prevention, (2) medication, and (3) surgical placement of a stimulator electrode at a specific anatomic site in the basal ganglia.