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Illustrative: satellite orbits, their ground swaths or the lines of sight a receiver keeps

Risk Academy, led by the Nexus Consortium · Technology and Digital Systems · Department of Cyber, Digital and Space Systems

Positioning, navigation, timing, satellite communication, space weather and debris

Space systems, space weather and navigation

Space systems, space weather and navigation covers the satellites, ground segments and services that provide positioning, navigation, timing and communication, and the risks to them from space weather, debris, interference and attack.

01Scope

What the discipline covers

The subtopics its courses and labs teach.

Courses
In preparation
Levels
In development
Labs
In development
  • Positioning, navigation and timing
  • Satellite communications
  • Space weather and its effects
  • Space debris and sustainability
  • Interference, jamming and spoofing
  • Ground segment resilience
  • Space system dependency of critical services
  • Space governance and data policy

Courses in development extend the scope to further subjects: Space weather risk and degraded operations; Space system dependency and resilience.

02Maps

Build a twin of any place

Search any place or open the world; the layers and generators follow space systems, space weather and navigation on the planet map, the globe and in 3D.

West Cornwall: Goonhilly and the Porthcurno cable landings: a flat plan of the faculty twin. Terrain 0 to 245 m; 4 satellite dishes; 74 communication masts and towers; 12 telephone exchanges; 7 data centres and cable landing stations; 12 aerodromes; 1 telecom offices; Communication line 161 km; 729 known exploited vulnerabilities since 2023-10-17; Night-time lights, VIIRS day-night band: read live when the 3D twin opens. Contours every 25 metres from the elevation grid; communication cables by class; ground infrastructure as marks.
West Cornwall: Goonhilly and the Porthcurno cable landings, United Kingdom. Flat plan of the same data: relief as contours from the inline grid, the mapped ground infrastructure by kind, the mapped cables and the numbers below. The 3D twin opens on devices that can draw it, once its data and code have been checked.
  • Terrain 0 to 245 m
  • 4 satellite dishes
  • 74 communication masts and towers
  • 12 telephone exchanges
  • 7 data centres and cable landing stations
  • 12 aerodromes
  • 1 telecom offices
  • Communication line 161 km
  • 729 known exploited vulnerabilities since 2023-10-17
  • Night-time lights, VIIRS day-night band: read live when the 3D twin opens
Credits and dates per layer are listed under the stage. Relief in the twin is exaggerated ×1.5 for legibility.

Drag to move, right drag or Shift with a drag to turn and tilt, Ctrl with the wheel to zoom. Keyboard: arrows move, Shift with arrows turn and tilt, + and – zoom, 0 resets, V steps through the views, Escape clears.

Flat plan of the same data: relief as contours from the inline grid, the mapped ground infrastructure by kind, the mapped cables and the numbers below. The 3D twin opens on devices that can draw it, once its data and code have been checked.

The boundaries, names and designations shown do not imply any judgement on the legal status of any territory, or any endorsement or acceptance of such boundaries. Countries: Natural Earth (public domain).

03Live map

Earth observation in the Amazon Basin

True-colour imagery, land cover, vegetation, snow and sea ice, over the Amazon Basin.

The interactive map needs JavaScript; the layer list and sources are below.

Layers 1

Earth observation

Latest available

NASA GIBS / EOSDIS · ASTER GDEM (METI, NASA) · Blue Marble (NASA) · © OpenStreetMap contributors (ODbL) · Natural Earth

Loading the latest NASA imagery.

Drag to move. Ctrl or ⌘ and scroll, pinch or the buttons to zoom; hover for the values under the pointer; reset returns to the region.

Earth observation, framed on the Amazon Basin.Satellite and model products as NASA publishes them, each with its own date. They are indicators, not assessments of any place.

Data: NASA GIBS · ASTER GDEM · Blue Marble · © OpenStreetMap contributors · Natural Earth · NASA EONETSources and licences

  • We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • VIIRS near-real-time products (flood, land surface temperature, snow cover, corrected reflectance), NASA LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • MODIS land products (vegetation indices, gross primary production, land cover), NASA LP DAAC and LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • GHRSST Level 4 MUR analyses, NASA Jet Propulsion Laboratory; distributed by the NASA Physical Oceanography DAAC (PO.DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • ASTER GDEM is a product of METI and NASA (ASTER Global Digital Elevation Model V003, NASA LP DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). Cite as: NASA/METI/AIST/Japan Spacesystems and U.S./Japan ASTER Science Team (2019). ASTER Global Digital Elevation Model V003. doi:10.5067/ASTER/ASTGTM.003. NASA open data
  • Made with Natural Earth. Free vector and raster map data @ naturalearthdata.com. Public domain
  • © OpenStreetMap contributors (ODbL), via NASA GIBS (coastlines, boundaries, roads and place names). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). ODbL
  • Blue Marble, NASA Earth Observatory; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • Context on the globe and flat map: coastlines, boundaries, roads and place names from NASA GIBS reference layers (OpenStreetMap data, ODbL, © OpenStreetMap contributors); Blue Marble imagery as an optional base; 3D terrain and the elevation read-out from the ASTER GDEM elevation colour index (5 m to 200 m classes, exaggerated for legibility). Boundaries are drawn as published and imply no position on any territory.
  • Globe: MapLibre GL JS 6.9.1, BSD-3-Clause, © MapLibre contributors.
  • Live events: NASA Earth Observatory Natural Event Tracker (EONET); events are indicative and keep their original source links.
  • Live: NASA EONET Events are indicative, not authority warnings.
  • NASA GIBS: We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS).
  • Past year, daily temperature and sunshine (NASA POWER): These data were obtained from the NASA Langley Research Center (LaRC) POWER Project funded through the NASA Earth Science/Applied Science Program..
  • Weather data by Open-Meteo.com (https://open-meteo.com/), licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/).
  • Optional layers (10 sources in the layer list: live, forecast, observed and context) print their provider credit on the map and here when switched on; forecasts are model output and derived indices are estimates.

Layers and dates

  • True colour: VIIRS NOAA-20 corrected reflectance, NASA LANCE · 13 Oct 2026
  • Land cover type (IGBP), yearly: MODIS Terra and Aqua land cover (MCD12Q1), NASA LP DAAC · 2024
  • Enhanced vegetation index, rolling 8 days: MODIS Terra EVI, NASA LANCE · 13 Oct 2026
  • Snow cover: VIIRS NOAA-20 NDSI, NASA LANCE · 13 Oct 2026
  • Sea ice concentration: GHRSST MUR, NASA JPL PO.DAAC · 12 Oct 2026

04The subject

The subject, methods and measures and debates and bodies

The field and its scope

For infrastructure operators, satellite and ground-segment engineers, regulators and emergency planners who must understand what space services their systems depend on and what degrades them.

05The method

From a miss distance to a manoeuvre: how a conjunction becomes a probability of collision

A conjunction's probability of collision follows from the predicted miss distance, the combined position uncertainty of both objects and their combined size; an uncertainty that is too small or too large moves the figure by orders of magnitude, and the manoeuvre decision compares it with a threshold near one in ten thousand.

Sources: Kessler and Cour-Palais, Collision frequency of artificial satellites: The creation of a debris belt (1978); Liou and Johnson, Risks in Space from Orbiting Debris (2006); Vallado, Crawford, Hujsak and Kelso, Revisiting Spacetrack Report #3 (2006); UNOOSA, Guidelines for the Long-term Sustainability of Outer Space Activities (2019).

06At a glance

At a glance, with 5 related topics

Space systems, space weather and navigation at a glance

risksacademy.comtechnology-digitaldiscipline

Space systems, space weather and navigation: 0 primary courses open, 2 in preparation and 0 also taught here, across 8 subtopics and 2 connected disciplines. Courses: RAS-418 L2 in preparation, RAT-262 L2 in preparation.Space systems, spaceweather and navigationRAS-418RAT-262
Space systems, space weather and navigation at a glance
  • Open, 0
  • In preparation, 2
  • Subtopics, 8
Course codes from the curriculum; study levels L1 to L4.
Twin builderBuild a twin of any placeWorked example: West Cornwall: Goonhilly and the Porthcurno cable landings · 4 generators · 7 layers · 3 instruments
07Console

How Space systems, space weather and navigation is taught, as a process you can run

Press Play to run this process from this page's own data.

08Learning

Learning, practice and connections

Achievements in this discipline

  1. Course achievements

    One for each course with this as its primary discipline, earned when you pass the course's assessed activities.

  2. Cross-faculty: Space and food

    Courses in connected disciplines and a passed integrative task. In development.

An achievement is a record of the learning completed and assessed here. How recognition works.

09Take part

Take part in Technology and Digital Systems

Start from who you are.

10References

Core references and where to begin

Start with Liou, then Kessler, then Vallado.

11Questions

Questions, answers and key terms

Is study here free?
Yes. Every course and learning material of Risk Academy, led by the Nexus Consortium, is free to study, self-paced or with a cohort. Ordinary participation has no fee; paid work, internships and fellowships are separate arrangements.
What does completing a course give me?
A completion record: the course, its version, the date and what was assessed, private by default and shared by you. It stacks into discipline, department and programme achievements. A record states what was studied and assessed and does not certify competence; it is not a licence, a professional title or an employment status.
Where do the data and the places come from?
Every faculty teaches on a twin of a real place built from open data; each layer carries its provider, licence and date, and every result on the Academy states its source. Maps and figures are indicators for teaching, never an assessment of a place.
How do I take part beyond the courses in space systems, space weather and navigation?
Form a competence cell of three to seven people, study a shared pathway, take a supervised assignment in the National Working Groups, or bring a cohort from your institution. For organisations.

Key terms

Term

Global navigation satellite system

Satellite constellations that provide positioning, navigation and timing worldwide.

Term

Space weather

Conditions on the Sun and in near-Earth space that can disrupt satellites, power grids and radio.

Term

Geomagnetic storm

A disturbance of Earth's magnetic field caused by solar activity.

Term

Orbital debris

Defunct satellites and fragments in orbit that threaten operating spacecraft.

ReportsContribute

Contribute evidence from this page.

Reports is the Consortium's quarterly publication. What you know about this subject can become evidence, a case or a correction in the next edition, credited to you and published under CC BY 4.0 where it is your own work.

Risk Academy
Space systems, space weather and navigation

Prepare with a related course

Open courses in connected disciplines teach the methods this discipline will build on.