More than two thousand satellites are currently in orbit. They measure the earth's surface characteristics, ocean currents, clouds and the gaseous content of the atmosphere. One of the oldest programs is Landsat. Run by both the National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS), Landsat is still widely used today because it provides its data to researchers free of charge.

Sustainable development supports the concept of lifting populations out of poverty without endangering resources and the environment for future generations. A wide range of past projects have attempted to achieve these objectives, but the United Nations Millennium Declaration in 2000 established for the first time an extensive partnership among nations to reduce global poverty through a specified framework of time-bound objectives. These goals and objectives, which are to be met by 2015, were agreed upon by 189 nations and have come to be known as the Millennium Development Goals (MDGs) (Table 1).

This year marks the halfway point in efforts to achieve the MDGs, and progress has been promising in some areas such as primary education and vaccination rates. However, demographic trends are interfering with efforts to achieve other goals. For example, increasing population exacerbates extreme poverty even as work is being done to mitigate it. Organizations such as the Center for Global Development (CGD) have recognized this impediment. Last month, CGD launched an initiative that calls for more adequate consideration of demographics in the formation of development policy.

Capturing and eating fish and rainforest wildlife, including large primates, for human sustenance has been practiced for generations. However, as human populations have grown and demand for these resources has increased, species in coral reefs and tropical rainforests--the most diverse ecosystem types on the planet--have been put in jeopardy.

Though both ailing fisheries and dwindling wildlife populations have received much attention and attempted remediation, these problems have been difficult to tackle because of competing interests among conservationists and fishermen/hunters who base their livelihood on harvesting wildlife. Two recently released studies offer new insight into the problem of harvesting wildlife, and perhaps even a solution.

More than 2,400 scientists and policymakers convened in Stockholm last month for the 2008 World Water Week summit. This year's summit was focused on sanitation access, although a variety of interdisciplinary research was presented for discussion.

Inadequate sanitation is a known cause of infectious diseases and death in the developing world. In response, improvement in sustainable access to safe drinking water and sanitation became part of the UN Millennium Development Goals.