--- title: "Constellations and orbits: Space and | Nexus Observatory" description: "Constellations and orbits, inside Space and satellite systems: LEO broadband constellations, MEO constellations, GEO high-throughput satellites…" url: https://observatory.global/space/constellations-and-orbits/ publisher: Nexus Observatory Inc. updated: 2026-10-29 --- [Nexus Observatory](https://observatory.global/) / [Space and satellite systems](https://observatory.global/space/) / **Constellations and orbits** # LEO, MEO and GEO, sized to revisit and coverage. Constellations and orbits, inside Space and satellite systems: LEO broadband constellations, MEO constellations, GEO high-throughput satellites, HEO (Molniya and Tundra-type) orbits and more. Every item is traced to its specification, from ITU RR Art. 22 (EPFD limits for NGSO) to ITU Resolution 35 (WRC-19) NGSO milestone deployment, and runs on the open Observatory Protocol. [Plan with us](https://observatory.global/contact/) Architecture [The protocol](https://observatory.global/protocol/specification/) **Technologies**: 9 **At the frontier**: 2 **Protocol functions**: 5 of 8 **Industries served**: 10 Reference design, drawn to scale · drag to turn · hover a part **01** What it is ## Orbits and constellations. The space segment end to end: orbits and constellations, spacecraft buses, communications and Earth observation payloads, inter-satellite links, tracking and command, space safety, launch, and the licensing and filings that let a system operate over a site. Every platform, sensor, processing level and ground-segment step that turns remote measurements of the Earth into calibrated, analysis-ready evidence for a site, a region or a network. Each technology below carries what it is, what we do with it, and the standard it is drawn against. Satellite and space systems ### LEO broadband constellations Hundreds to thousands of satellites at 300–2,000 km giving low-latency broadband and backhaul to remote and northern sites. We design, integrate, deploy and operate. ITU RR Art. 22 (EPFD limits for NGSO) · ITU Resolution 35 (WRC-19) NGSO milestone deployment · 3GPP TS 38.300 (NTN, Rel-17) Satellite and space systems ### MEO constellations Satellites at roughly 8,000–20,000 km used for navigation and for high-capacity, lower-latency trunking than GEO. We design, integrate and operate. ITU RR Art. 22 · Rec. ITU-R S.1503 (EPFD computation) Satellite and space systems ### GEO high-throughput satellites Fixed-position spot-beam satellites at 35,786 km for broadcast, trunking and wide-area coverage where latency is acceptable. We design, integrate and operate. ITU RR Art. 9 and Art. 11 (coordination and notification) · ITU RR Appendices 30, 30A and 30B (planned bands) Satellite and space systems ### HEO (Molniya and Tundra-type) orbits Highly elliptical orbits that dwell over high latitudes, giving persistent Arctic coverage that GEO cannot reach. We design, integrate and operate. ITU RR Art. 22 · Rec. ITU-R S.1503 Satellite and space systems ### Sun-synchronous and polar orbits for EO Orbits with fixed local solar time and global coverage, used by most imaging and sounding missions; drive revisit and downlink planning. We design and integrate. CCSDS 502.0-B (Orbit Data Messages) · ECSS-E-ST-10-04C (space environment) Satellite and space systems ### Constellation design and coverage analysis Plane count, phasing, inclination and altitude trade studies that set revisit, capacity, latency and gateway demand for a service area. We design. CCSDS 502.0-B (Orbit Data Messages) · Rec. ITU-R S.1503 **Frontier** · Satellite and space systems ### HAPS and HIBS stratospheric platforms Platforms at 20–50 km acting as relays or IMT base stations, filling the gap between towers and satellites. We design, integrate and deploy. ITU RR No. 1.66A (HAPS definition) · ITU Resolution 221 (Rev. WRC-23) HIBS **Frontier** · Satellite and space systems ### Very low Earth orbit (VLEO) Orbits below about 450 km with higher-resolution sensing and lower latency, traded against drag, atomic oxygen and short lifetimes. We design. ECSS-E-ST-10-04C (space environment) Remote sensing and Earth observation ### Geostationary imagers and sounders Continuous hemispheric views every few minutes for weather, fire, smoke and flood watch over a site. We integrate and deploy. WMO OSCAR/Space · CGMS baseline for the operational space-based observing system **02** Architecture ## Where it sits, and what it speaks. Constellations and orbits draws on 3 domains and 24 layers of the spectrum; the highlighted layers carry this area. It speaks 5 of the protocol's 8 core functions. Orbits and constellations 8 Spacecraft buses and platforms 9 Communications payloads, NTN and direct-to-device 9 Inter-satellite and space-to-ground links 7 Earth observation payload classes 10 Tracking, telemetry and command and space safety 9 Launch, licensing and regulation 8 Frontier and research 6 Gateways and teleports 8 User terminals 9 Baseband, modems and software-defined radio 8 Ground-station-as-a-service and antenna networks 7 CCSDS protocol stacks 9 Mission control and flight dynamics 7 Data downlink, processing and distribution 8 Earth station spectrum coordination and interference 7 01**Join** Identity, attestation quote, signed policy. 02**Admit** Admitted for a stated scope, nothing wider. 03**Describe** What, where, how and by whom, with calibration. 04**Time** One clock across the grid, with its error bound. 05**Observe** Every value with quality and provenance. 06**Qualify** Tested against the specification, state on record. 07**Federate** Signed exchange across grids and trust domains. 08**Orchestrate** Software and configuration by signed plan. **03** On the grid ## Every site joins one observing grid. The open networks on the grid today, over real relief and the geodesic cells we count them into, filtered to the space domain this area serves. A site built here enrols into the same grid. **04** In the field ## Where this runs, sector by sector. 6 deployment scenarios from the sector research that rely on constellations and orbits. [Government and public safety Deployable communications and sensing for incident commandA cell on wheels with satellite backhaul, mesh telemetry and environment nodes at the incident base.](https://observatory.global/sectors/public-safety/) [Development and humanitarian School connectivity with a school observatorySatellite or fixed wireless, school Wi-Fi, an open connectivity probe and an optional station.](https://observatory.global/sectors/humanitarian/) [Development and humanitarian Displacement-site connectivity and sensingPoint-to-multipoint wireless, satellite backhaul, solar and water-point sensors with protection safeguards.](https://observatory.global/sectors/humanitarian/) [Scientific Ocean and coastal low-cost buoy arraysSatellite-backhauled wave buoys accepted in a national programme trial.](https://observatory.global/sectors/scientific/) [Transport Highway corridor mobile coverage for safetySmall cells and satellite backhaul along unserved roads.](https://observatory.global/sectors/transport/) [Government and public safety National GBON surface and upper-air networkWMO-grade stations reporting through WIS 2.0, funded through the systematic-observations financing pathway.](https://observatory.global/sectors/public-safety/) **05** Open and enterprise ## Open by default. Enterprise by contract. The open counterpart lives on the main site for anyone to read and run. The enterprise service is designed, deployed and operated with you, under contract. Open, on the main site - Orbit and pass methods - Payload class catalogue - Ground-station interfaces on the protocol Enterprise, on this site - Mission and payload integration - Tasking and downlink services - Non-terrestrial backhaul for remote sites **06** The rest of the line ## Space and satellite systems, area by area. [Space and satellite systems Spacecraft and payloadsBuses and optical, radar and RF payload classes.](https://observatory.global/space/spacecraft-and-payloads/) [Space and satellite systems NTN and direct-to-device3GPP non-terrestrial networks, from orbit to handset.](https://observatory.global/space/ntn-and-direct-to-device/) [Space and satellite systems Tasking and downlinkRequest, schedule, receive and process: one chain.](https://observatory.global/space/tasking-and-downlink/) [Space and satellite systems Space safetyTracking, telemetry and command, conjunction awareness.](https://observatory.global/space/space-safety/) [Space and satellite systems Licensing and spectrumFilings, coordination and earth-station rules, by country.](https://observatory.global/space/licensing-and-spectrum/) ## Bring us the site. Survey, design, deployment and operation for constellations and orbits. The form names who receives your details. [Talk to us](https://observatory.global/contact/) [contact@observatory.global](mailto:contact@observatory.global?subject=Space%20and%20satellite%20systems%3A%20Constellations%20and%20orbits) [Nexus Observatory](https://observatory.global/)**Space and satellite systems** . From orbit to the ground, on one protocol.[Talk to us](https://observatory.global/contact/) Space and satellite systems - [Constellations and orbits](https://observatory.global/space/constellations-and-orbits/) - [Spacecraft and payloads](https://observatory.global/space/spacecraft-and-payloads/) - [NTN and direct-to-device](https://observatory.global/space/ntn-and-direct-to-device/) - [Tasking and downlink](https://observatory.global/space/tasking-and-downlink/) - [Space safety](https://observatory.global/space/space-safety/) - [Licensing and spectrum](https://observatory.global/space/licensing-and-spectrum/) Technologies - [Orbits and constellations](https://observatory.global/technologies/satellite/orbits-and-constellations/) - [Spacecraft buses and platforms](https://observatory.global/technologies/satellite/spacecraft-buses-and-platforms/) - [Gateways and teleports](https://observatory.global/technologies/ground/gateways-and-teleports/) - [User terminals](https://observatory.global/technologies/ground/user-terminals/) - [Platforms and orbits](https://observatory.global/technologies/eo/platforms-and-orbits/) - [Optical, spectral and thermal sensors](https://observatory.global/technologies/eo/optical-spectral-and-thermal-sensors/) Industries - [Public safety](https://observatory.global/industries/public-safety/) - [Humanitarian](https://observatory.global/industries/humanitarian/) - [Climate](https://observatory.global/industries/climate/) - [Nature](https://observatory.global/industries/nature/) - [Oceans](https://observatory.global/industries/oceans/) - [Agriculture](https://observatory.global/industries/agriculture/) - [Telecom](https://observatory.global/industries/telecom/) Service platforms - [Observatory Protocol](https://observatory.global/protocol/) - [Protocol & Grid](https://observatory.global/grid-services/) - [Software](https://observatory.global/software/) - [Hardware & power](https://observatory.global/hardware/) - [Sensors & instruments](https://observatory.global/sensors/) - [Connectivity](https://observatory.global/connectivity/) - [Edge compute & AI](https://observatory.global/edge-ai/) © 2026 Nexus Observatory Inc. 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