Welcome to the web pages of Space Geodetic Observation Center(SGOC).
SGOC is the 16th geodetic VLBI observatory in the world and the 3rd in Asia, and
the pioneer of the new era of space geodetic survey in South Korea.
Long distance measurements
VLBI is most precise geodetic technique for determining distance between continents in millimeter scale.
VLBI installed in Sejong will be expected to be a datum point in Korea for positioning observation.
The observation for continental drift
The surface of the Earth consist of a series of plates which are in motion slowly.
Many earthquakes and tsunami happen by this movement. VLBI system can measure the movement of plates
and a variety of natural disasters can be prevented by the data from VLBI measurement.
The reference for the determination of universal time
The irregular change of Earth rotation cause the difference of universal time.
VLBI system is observing and monitoring this time difference and measures change of length of day from accumulated data.
VLBI provides Earth rotation parameter and the reference of universal time.
The earth’s movement
- UT1 : Universal time based on the Earth rotation.
- Precession : A change in the orientation of the rotational axis of a rotating body.(period is 25800 years)
- Nutation : A rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet,
or bullet in flight, or as an intended behavior of a mechanism.