The State of the Environment—An Overview - National Aeronautics And Space Administration's Missions To Planet Earth

In the past three decades humans have changed the way they think about the planet Earth. Missions to other planets have found those planets interesting and diverse but also sterile. Earth is unique; as far as is known, it is the only planet capable of sustaining life.

While environmental change is certain, many things remain unknown. Among those things is how humans alter Earth. One way to study the effects of humans on Earth as a whole is from space. Since 1991 the National Aeronautics and Space Administration (NASA) has undertaken a comprehensive program to study the planet as an environmental system. The program was originally called Mission to Planet Earth, but is now called Earth Science Enterprise. By using satellites and other tools focused on Earth, scientists hope to expand what is known about how natural processes affect humans and how humans may, in turn, impact the planet.

Earth Science Enterprise has three components: a series of Earth-observing satellites, an advanced data system, and teams of scientists and researchers who study the data collected. Key areas of study include clouds, water and energy cycles, oceans, atmospheric chemistry, land surface, water and ecosystem processes, glaciers and polar ice sheets, and the solid earth.

Phase I of the program comprised satellites, space shuttle missions, and various land- and airborne-based studies. Phase II began April 15, 1999 (delayed from 1998 because of technical problems), with the launch of Land-sat 7 from Vandenberg Air Force Base in California. The first Earth Observing System (EOS) satellite, Landsat 7 has the goal of taking an estimated 250 photographs of Earth each day. These will be available not only for FIGURE 1.10
Ratings of government agencies, September 2003 national security purposes but also to private-sector, commercial, and academic segments of society to help answer pressing environmental questions in all the areas of study. The latest satellite launch occurred on June 24, 2002, when the NOAA-M satellite was launched to collect meteorological data and to monitor environmental events around the world.

FIGURE 1.11
Public level of involvement in the environmental movement, 2004

FIGURE 1.12
Public participation within the past year in various activities, March 2003

FIGURE 1.13
Public participation in activities that affect the environment

FIGURE 1.14
Public opinion on which should take priority—the environment or the economy, 1984–2004

FIGURE 1.15
Public opinion on which should take priority—the environment or the economy, 2004

FIGURE 1.16
Worries of young adults based on 2002–2003 data