// ORBITAL LOGISTICS AND PROPULSION TERM
Descending Node
The point where an orbiting object crosses from above to below a reference plane, such as the Earth's equatorial plane.
TECHNICAL DEFINITION
The descending node is one of the orbital nodes where an orbiting body (e.g., satellite) crosses the reference plane (e.g., Earth's equatorial plane, ecliptic) moving from north to south, an essential orbital element.
BACKGROUND
Rome is the capital city and most populated comune (municipality) of Italy. It is also the administrative centre of the Lazio region and of the Metropolitan City of Rome. A special comune named Roma Capitale with a population of 2.7 million in an area of 1,287.36 km2 (497.1 mi2), Rome is the third most populous city in the European Union by population within city limits. The Metropolitan City of Rome Capital, with a population of 4.2 million, is the most populous metropolitan city in Italy. Its metropolitan area is the third-most populous within Italy. Rome is located in the central-western portion of the Italian Peninsula, within Lazio (Latium), along the shores of the Tiber Valley. Vatican City is an independent country inside the city boundaries of Rome, the only existing example of a country within a city. Rome is often referred to as the "City of Seven Hills" due to its geography, and also as the "Eternal City". Rome is generally considered to be one of the cradles of Western civilization and Western Christian culture, and the centre of the Catholic Church.
READ MORE ON WIKIPEDIASYNONYMS & ALIASES
- Southbound crossing
- Downward node
USAGE NOTE
Sun-synchronous orbits are often designed to cross the equator at a specific local time at the descending node for consistent lighting conditions.
DEVELOPERS
Organizations developing technology related to Descending Node.
Developer of Systems Tool Kit (STK), a physics-based software platform used extensively for modeling, simulating, and analyzing missions for space, defense, and intelligence systems. The software's core function is calculating and visualizing orbital mechanics, where the descending node is a fundamental parameter for defining an orbit's orientation.
Provides space situational awareness (SSA) and space traffic management services by operating a global network of phased-array radars. LeoLabs tracks satellites and debris in Low Earth Orbit, providing high-resolution orbital data, including all classical orbital elements like the position of the descending node, to satellite operators.
Operates the world's largest commercial network of optical telescopes for tracking and characterizing objects in geosynchronous orbit (GEO) and beyond. Their services provide precise orbital determination and space domain awareness, which relies on the accurate calculation of all orbital parameters, including nodal crossings.
Develops space situational awareness and data analytics platforms that aggregate data from multiple sources to provide a comprehensive picture of the orbital environment. Their software is used for collision avoidance and tracking, which necessitates constant calculation and prediction of satellite orbits and their nodes.
Provides satellite ground systems, including command and control (C2) software. This technology is used to operate satellites, manage their health, and maintain their orbits (station-keeping), which involves precise maneuvering based on parameters like the descending node.
As the operator of the Starlink satellite constellation, SpaceX manages thousands of satellites in LEO. This requires an advanced, automated system for orbital determination, prediction, and collision avoidance that continuously processes the orbital elements, including the nodes, for every satellite.
A launch service provider that specializes in delivering small satellites to precise and unique orbits. Their launch vehicles' guidance, navigation, and control (GNC) systems are designed to achieve highly accurate orbital insertions, defined by specific parameters such as inclination and the longitude of the ascending/descending node.
Operates the largest fleet of Earth observation satellites. Maintaining the desired ground track for their imaging constellation requires precise orbital control and station-keeping, which is fundamentally dependent on managing the orbit's nodal precession and crossing points.