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Glossary

E

Echo Sounders

Devices that use sound waves to measure the depth of surface water bodies.

ecosystems

the complex of a community of organisms and its environment functioning as an ecological unit


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EDL

Entry, Descent and Landing

El Nino

Warm-water conditions off the western tropical coasts of the Americas, occurring irregularly but usually around Christmastime, caused by weakening trade winds and causing depleted fisheries, heavier-than-normal rain in the central and eastern Pacific, and drought in the western Pacific.


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emissions

The production of light, or more generally, electromagnetic radiation by an atom or other object.


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EOS

Earth Observing System

EOSDIS

EOS Data and Information System

EPA

Environmental Protection Agency

Ephemeris

An ephemeris is a tabulation of computed positions and velocities (and/or various derived quantities such as right ascension and declination) of an orbiting body at specific times. The plural form of ephemeris is ephemerides. In the context of this web-site, solar system bodies are implied.


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EPO

Education and Public Outreach. See Opportunities in Science Mission Directorate Education and Public Outreach.

equilibrium

the state where conditions in a fluid are uniform or changing only slowly

ESA

European Space Agency

ESIP

Federation of Earth Science Information Partners

ESMD

Exploration Systems Mission Directorate

ESSP

Earth System Science Pathfinder

ESTO

From instruments to data access, the NASA Earth Science Technology Office (ESTO) develops technologies that enable a full range of scientific measurements, operational requirements, and practical applications that benefit society at large.

extra solar planets

Planets around stars other than the Sun.


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