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Nexus Observatory Inc. keeps a record of each choice as proof: a random consent ID, the time, your region and the rules applied, the choices, the notice shown, the page, a shortened IP address, a one-way code of your browser type and, if you are signed in, your account. Records are kept while your choice applies and for 3 years after, then deleted.Nexus Observatory Inc. conserve un registre de chaque choix à titre de preuve : un identifiant de consentement aléatoire, l'heure, votre région et les règles appliquées, les choix, l'avis affiché, la page, une adresse IP abrégée, un code à sens unique du type de navigateur et, si vous êtes connecté, votre compte. Les registres sont conservés tant que votre choix s'applique et pendant 3 ans par la suite, puis supprimés.
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Constellations and orbits: ground tracks of a constellation computed over a hidden-line Earth. The loop, step by step: 1. Satellites circle the Earth on set orbits. 2. One satellite crosses its orbital plane. 3. Sensors check that the response worked. 4. Its ground track sweeps across the continent. 5. Each reading is stamped with time and place. 6. Signatures are checked before any model runs. 7. Revisit time is computed for the whole fleet. 8. The edge releases confirmed results only. 9. The next satellite follows within minutes. 10. The relay forwards sealed packets untouched. 11. Coverage gaps appear on the planning map. 12. The console shows the evidence with the alert. 13. An extra plane closes the longest gap. 14. Instruments confirm the response took effect. 15. The whole chain is archived for audit. 16. Everything settles back to idle.
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Satellites circle the Earth on set orbits
Nexus Observatory/
Space and satellite systems/
Constellations and orbitsConstellations 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 usArchitectureThe protocol01What it is
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. Each technology below carries what it is, what we do with it, and the standard it is drawn against.
Satellite and space systems
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
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
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
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
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
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
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
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)
02Architecture
Constellations and orbits draws on the spectrum below; the highlighted layers carry this area, and the protocol functions it speaks are marked.
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
01Join Identity, attestation quote, signed policy.
02Admit Admitted for a stated scope, nothing wider.
03Describe What, where, how and by whom, with calibration.
04Time One clock across the grid, with its error bound.
05Observe Every value with quality and provenance.
06Qualify Tested against the specification, state on record.
07Federate Signed exchange across grids and trust domains.
08Orchestrate Software and configuration by signed plan.
09Correct A correction marks what depends on it and publishes a new version.
10Exchange Products reach people and applications through versioned interfaces.
11Prove Signed proof receipts that an independent verifier can check.
12Exit and decommission An open exit path, and a record that closes.
03On the grid
Real elevation, line of sight, an orbit swath and a GeoAI pass, each an interactive explainer on open terrain data with its source shown.
04In the field
Deployment scenarios from the sector research that rely on constellations and orbits.
Government and public safety05Open and enterprise
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
Enterprise, on this site
06The rest of the line
Survey, design, deployment and operation for constellations and orbits. The form names who receives your details.
Talk to usAsk for a quoteMore presentations
Each opens as a full-screen presentation: deeper pages on the same subject, explainers, stories, guided tours of the places, network scenes and the observatories that came before.
All presentations for this pageConstellations 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.
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.