Geographers make frequent use of satellites. These are of two varieties: weather
satellites and Earth resources satellites. Weather satellites have been in orbit since
1960 and geographers have used them to study all manner of phenomena ranging
from severe storms to seasonal mountain snowpacks to the monitoring of El Nin ̃o.
Earth resources satellites are polar orbiters and have been used for purposes such
as monitoring land use change, identifying prehistoric habitation sites, and esti-
mating citypopulations. The large area views afforded by satellites have aided
in refining our knowledge of the physical and cultural features of Earth and dis-
covering spatial relationships between seemingly disparate elements. Some uses
depend on the “picture” qualities of the satellite data. Yet, it must be remembered
that these are “images” with no film involved. The data are used in digital form
and, as such, the numeric data generatedcanbeusedinsophisticatedmodeling
such as observing the components of Earth’s energy balance or automated detec-
tion of change in Earth surface properties over time. The various satellites can
detect energy in both visible and invisible wavelengths so that combined informa-
tion is able to make more assessments and environmental models more certain.Satellite State
A satellite state is a country that lies in the “orbit,” metaphorically, of a larger,
more powerful country, meaning that it owes political allegiance or economic trib-
ute to the more powerful state. Before the 20th century, such states were typically
referred to as “vassal states,” “tributary states,” “puppet states,” or “client states.”
The governance of such states is frequently characterized by authoritarian or
totalitarian political structures, and satellite states may compose abuffer zone
between empires; thus historically they have played a role inimperialismand
geopolitics. In some cases, a satellite state functions in a fashion similar to a
colony, in that its foreign policy aligns closely with that of the more powerful state
to which it is subordinate. However, a satellite state differs from a colony or a
dependency in that it is a de jure sovereign power, despite the fact that such sover-
eignty is compromised by its satellite status. Furthermore, satellite countries may
form an economic bloc with the dominant power, based on a shared ideology or
simply to enhance the development and authority of the dominant polity. The term
was widely employed by both politicians and scholars during the Cold War, espe-
cially in relation to the communist states of Eastern Europe. “Finlandization” is a
related term also used during the same era. In this case, Finland was not subject to
the same degree of domination as most of the Eastern European countries, but294 Satellite State