A

Alternate Name
An alternate name or designation of a space object that may differ from the name included in the source database.
Apogee
The point in a space object’s orbit at which it is farthest from the Earth; the distance between this furthest point and the Earth’s center.
Apogee Altitude
A space object’s maximum orbital altitude; the distance between its apogee and the Earth’s surface.
Argument of Perigee
The angular position of a space object’s perigee; a description of an orbital trajectory’s orientation within its orbital plane.
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C

Contractor
The organization that was primarily contracted to develop a satellite.
Country of Jurisdiction
The country that has administrative control and jurisdiction over a space object.
Further Reading
Country of Launch Site
The country that possesses the geographic territory from which a space object was launched into orbit.
Further Reading
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D

Drift Rate
The rate at which an object in geosynchronous Earth orbit moves east or west as measured in geodetic longitude space.
Further Reading
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E

Earth Radius
The average distance between the center of the Earth and its surface.
Further Reading
Eccentricity
An orbit’s deviation from a perfect circle; values near zero refer to nearly circular orbits, whereas those closer to one are more elongated.
Further Reading
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I

Inclination
The angle of a satellite’s orbital plane relative to the Earth’s equatorial plane.
Further Reading
International Designator (COSPAR)
A unique identifier assigned to artificial objects launched into space.
Further Reading
International Telecommunications Union (ITU)
A specialized agency of the United Nations responsible for protecting space systems against harmful interference in the radio-frequency spectrum.
Further Reading
ITU Catalog Date
The date at which space network licenses from the ITU were cataloged; some licenses may have expired or been added since this date.
Further Reading
ITU Filing Longitude
The orbital position allocated to geostationary satellites as part of a license filed with the International Telecommunications Union.
ITU Frequency Band
The radio-frequency band(s) allocated to geostationary satellites as part of a license filed with the International Telecommunications Union.
Further Reading
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L

Launch date
The calendar date on which a space object was launched into space.
Launch Site
The spaceport or other platform from which an object was launched into space.
Further Reading
Launch Vehicle
The name of the launch vehicle that placed an object into orbit.
Further Reading
Lifetime
The estimated or planned operational lifetime of a space object.
Longitude
The location of a geostationary satellite along the Earth’s Equator.
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M

Mean Motion
The average angular velocity of a space object in orbit.
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N

NORAD ID (Satellite Catalog Number)
An identification number assigned sequentially to space objects by the U.S. Space Command in the order in which they were observed.
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O

Operator
The entity that operates or controls a space object.
Orbital Period
The time it takes a space object to complete one full orbit.
Mean Orbital Speed
The average speed or velocity of a space object as it moves along its orbital trajectory.
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P

Perigee
The point in a space object’s orbit at which it is closest to the Earth; the distance between this closest point and the Earth’s center.
Perigee Altitude
A space object’s minimum orbital altitude; the distance between its perigee and the Earth’s surface.
Purpose
The discipline in which the satellite is used in broad categories.
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R

Right Ascension of the Ascending Node (RAAN)
An angular orbital parameter that specifies the orientation of a space object’s orbital plane relative to the First Point of Aries.
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S

Semi-major Axis
One half of the a space object’s major orbital axis; a common measurement an orbit’s general size.
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T

Type
The type of space object (active payload, inactive payload, rocket body, debris, or uncategorized)
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