Geodesy and Gravity Practice Flashcards

Vocabulary flashcards covering key terms, historical figures, gravity corrections, and geodetic applications.

Cartography

The art of displaying the final product of geodesy.

Bouguer correction

The gravity correction that accounts for the effect of the rock mass.

Space science

The field that relies on the Earth's external gravity field to predict orbits of space vehicles.

Hydrography

The branch of study that uses geodetic positional information specifically at sea.

Terrain correction

The gravity correction caused by variations in local topography.

Relative Method by Pendulum (or Relative determination of gravity)

The method that determines the difference in gravity between two or more locations.

Christiaan Huygens

The scientist who investigated pendulum motion and related clock developments.

Erathosthenes

The historical figure recognized as the founder of geodesy.

Gravity anomalies

The term defined as the difference between observed gravity and predicted values.

Henry Kater

The individual who developed the reversible pendulum.

Geodetic pendulum

A pendulum with finite size, mass distribution, a real pivot, and a rigid or semi-rigid support designed to make its period reproducible.

Pendulum law

The law stating that a pendulum swings more slowly where gravity is weaker and more quickly where gravity is stronger.

Simple pendulum

An ideal pendulum model defined as a point-like mass suspended by a massless line.

Engineering projects

The geodetic application used for large structures like dams and bridges.

Boundary demarcation

The geodetic application responsible for oil and gas leases.

Free air correction

The gravity correction that accounts for the decrease of gravity with increasing heights.

Jean Richer

The scientist who discovered that gravity varies with geographic location.

Geoid

The figure of the Earth that is everywhere normal to the force of gravity.

Free-Fall Gravimeter

A modern absolute gravimeter that determines gravity specifically by observing the motion of a test mass in free fall.

Stevin

The scientist who introduced gravity to the study of geodesy.

Absolute Method by Pendulum (or Absolute determination of gravity)

The method where the actual gravity value at a station is determined directly.

Geodesy

The discipline that presents the Earth's size, shape, and orientation, and serves as the theoretical foundation of surveying.

Ballistic gravimeter

An absolute gravimeter that determines gravity by observing the motion of a freely falling object.

Astronomy

The field of study that utilizes geodesy for monitoring the rotation of the Earth.

Drift correction

The gravity correction that compensates for temperature changes and elastic creep in instrument springs.

Eudoxus

The scholar who created the first star maps and calculated the solar year to be $365.25$ days.

Gravity control stations

A designated location where a reliable gravity value has been established.

Reversible pendulum

A pendulum suspended from two different pivots and observed in both orientations.

Elevation correction

The gravity correction formed by combining the free air and Bouguer corrections.

Aristoteles

The philosopher who formulated the argument for the sphericity of the Earth and gave the first hints of gravity.

Clarke 1866

The reference spheroid defined by parameters $a = 6,378,206$ and $b = 6,356,584$.

Gauss

The mathematician who defined the geoid.

Oceanography

The discipline that relies on geodesy to determine the location and movements of shorelines.

Spongler & Libby

The duo whose theory of gravity surveying is directly dependent on Newton's law of gravity.

Tide correction

The gravity correction that accounts for the gravity effects of celestial bodies such as the Sun and Moon.

Thales of Miletus

The scholar credited with the first documented ideas about geodesy.

Picard

The scientist responsible for the first modern measurement of the Earth.