The future of space

Purpose of space progra

The world food situation: New driving forces and required actions

"The world food situation is currently being rapidly redefined by new driving forces. Income growth, climate change, high energy prices, globalization, and urbanization are transforming food consumption, production, and markets. The influence of the private sector in the world food system, especially the leverage of food retailers, is also rapidly increasing. Changes in food availability, rising commodity prices, and new producer–consumer linkages have crucial implications for the livelihoods of poor and food-insecure people. Analyzing and interpreting recent trends and emerging challenges in the world food situation is essential in order to provide policymakers with the necessary information to mobilize adequate responses at the local, national, regional, and international levels. It is also critical for helping to appropriately adjust research agendas in agriculture, nutrition, and health. Not surprisingly, renewed global attention is being given to the role of agriculture and food in development policy, as can be seen from the World Bank's World Development Report, accelerated public action in African agriculture under the New Partnership for Africa's Development (NEPAD), and the Asian Development Bank's recent initiatives for more investment in agriculture, to name just a few examples." from TextWorld food situation, Globalization, food security, Agricultural production, Markets, Food prices,

Food and financial crises: Implications for agriculture and the poor

"High food prices from 2007 through mid-2008 had serious implications for food and nutrition security, macroeconomic stability, and political security. The unfolding global financial crisis and economic slowdown have now pushed food prices to lower levels. Yet the financial crunch has also decreased the availability of capital at a time when accelerated investment in agriculture is urgently needed. The food and financial crises will have strong and long-lasting effects on emerging economies and poor people. A synchronized response is needed to ease the burden on the poor and allow agriculture to face new challenges and respond to new opportunities. Three sets of complementary policy actions should be taken: (1) promote pro-poor agricultural growth, (2) reduce market volatility, and (3) expand social protection and child nutrition action. Agriculture requires strategic investment action, and the food-insecure poor need a bailout now." from Textfood security, Nutrition security, Pro-poor growth, Agricultural growth, Food prices, Social protection, Global financial crises,

Extrasolar Planets and Their Host Stars

In order to understand the exoplanet, you need to understand its parent star. Astrophysical parameters of extrasolar planets are directly and indirectly dependent on the properties of their respective host stars. These host stars are very frequently the only visible component in the systems. This book describes our work in the field of characterization of exoplanet host stars using interferometry to determine angular diameters, trigonometric parallax to determine physical radii, and SED fitting to determine effective temperatures and luminosities. The interferometry data are based on our decade-long survey using the CHARA Array. We describe our methods and give an update on the status of the field, including a table with the astrophysical properties of all stars with high-precision interferometric diameters out to 150 pc (status Nov 2016). In addition, we elaborate in more detail on a number of particularly significant or important exoplanet systems, particularly with respect to (1) insights gained from transiting exoplanets, (2) the determination of system habitable zones, and (3) the discrepancy between directly determined and model-based stellar radii. Finally, we discuss current and future work including the calibration of semi-empirical methods based on interferometric data.Comment: 80 pages in SpringerBrief format containing a few blank pages, 16 figures, 1 table of all stars with high-precision interferometric diameters, glossary of commonly encountered terms, SpringerBrief 2017, ISBN 978-3-319-61198-

Exoplanetary Transit Constraints Based Upon Secondary Eclipse Observations

Transiting extrasolar planets provide an opportunity to study the mass-radius relation of planets as well as their internal structure. The existence of a secondary eclipse enables further study of the thermal properties of the the planet by observing at infrared wavelengths. The probability of an observable secondary eclipse depends upon the orbital parameters of the planet, particularly eccentricity and argument of periastron. Here we provide analytical expressions for these probabilities, investigate their properties, and calculate their values for the known extrasolar planets. We furthermore quantitatively discuss constraints on existence and observability of primary transits if a secondary eclipse is observed. Finally, we calculate the a-posteriori transit probabilities of the known extrasolar planets, and we present several case studies in which orbital constraints resulting from the presence of a secondary eclipse may be applied in observing campaigns.Comment: 7 pages, 5 figures, 1 table; accepted for publication in PAS

Constraints on Secondary Eclipse Probabilities of Long-Period Exoplanets from Orbital Elements

Long-period transiting exoplanets provide an opportunity to study the mass-radius relation and internal structure of extrasolar planets. Their studies grant insights into planetary evolution akin to the Solar System planets, which, in contrast to hot Jupiters, are not constantly exposed to the intense radiation of their parent stars. Observations of secondary eclipses allow investigations of exoplanet temperatures and large-scale exo-atmospheric properties. In this short paper, we elaborate on, and calculate, probabilities of secondary eclipses for given orbital parameters, both in the presence and absence of detected primary transits, and tabulate these values for the forty planets with the highest primary transit probabilities.Comment: 3 pages, 1 figure, 1 table; to appear in ASP Conf. Proceedings: "Pathways Towards Habitable Planets" 2009, Barcelona, Spain (eds.: D. Gelino, V. Coude du Foresto, I. Ribas

Physical and virtual global food reserves to protect the poor and prevent market failure:

"The current food crisis has several causes—rising demand for food and feed, biofuels, high oil prices, climate change, stagnant agricultural productivity growth—but there is increasing evidence that the crisis is being made worse by the malfunctioning of world grain markets. Given the thinness of major markets for cereals, the restrictions on grain exports imposed by dozens of countries have resulted in additional price increases. A number of countries have adopted retail price controls, creating perverse incentives for producers. Speculative bubbles have built up, and the gap between cash and futures prices has risen, stimulating overregulation in some countries and causing some commodity exchanges in Africa and Asia to halt grain futures trading. Some food aid donors have defaulted on food aid contracts. The World Food Programme (WFP) has had difficulty getting quick access to grain for its humanitarian operations. Developing countries are urgently rebuilding their national stocks and re-examining the “merits” of self-sufficiency policies for food security despite high costs. These reactions began as consequences, not causes, of the price crisis, but they exacerbate the crisis and increase the risks posed by high prices. By creating a feedback loop with high food prices, they further increase price levels and volatility, with adverse consequences for the poor and for long-term incentives for agricultural production. Because they impede the free flow of food to where it is most needed and undermine the flow of price signals to farmers, these market failures impose enormous efficiency losses on the global food system, hitting the poorest countries and people hardest." from Author's textFood prices, Food policy, Markets,