The point at which the orbit of an earth satellite intersects the plane of the equator going from north to south.

the point at which an orbiting body rises through the plane of the ecliptic traveling southward

In an orbit, the place where a body crosses the plane of another orbit (usually, the Earth's orbit), heading south.

The direction in a planets orbit when it crosses from north to south as it passes through the ecliptic.

the point at which an orbit crosses the ecliptic plane going south

The position in the orbit of a planet (or the Moon) where it crosses the plane of the ecliptic, moving southward.

The point of a planet's orbit at which it crosses the plane of the earth's orbit extended to meet the celestial body from north to south.

The point at which an orbiting object or spacecraft, moving from north to south, crosses the plane of the equator.

The point in the orbit of an object, when it crosses the ecliptic whilst travelling north to south.

The point in a satellite's orbit at which it crosses the equatorial plane from north to south. See diagram, Keplerian elements.

Direction that a satellite is travelling relative to the Equator. A descending node would imply a southbound Equatorial crossing.

Refers to the sub-satellite point of a satellite pass when the satellite crosses the equator from the Northern Hemisphere into the Southern Hemisphere.

The point in the orbit of the Moon where it passes from above the ecliptic plane to below (see node).

The point on the ground track of the satellite orbit where the sub-satellite point (SSP) crosses the equator from the Northern Hemisphere into the Southern Hemisphere.

South Node. See Nodes.

The southbound equatorial crossing of a polar-orbiting satellite, given in degrees longitude, date, and universal time (UTC) for any given orbit or pass; the point at which a satellite crosses the equatorial plane heading south.