For teachers
Space Radar in the classroom
A free 3D map of the Solar System, the satellites above you and the stars beyond, in a browser: no account to make, nothing to install, no tracking, and it works with no internet from a copy you download once.
Or take it offline: three steps below.
What it needs
A computer from the last eight years or so, with Chrome, Edge, Firefox or Safari. No login, no licence key, no personal data in any request: nobody is tracked. To run a copy offline, Python 3 (most Macs and Linux machines have it) to serve a folder.
A running offline copy in three steps
- Download
space-radar-<version>.zipfrom the Releases page and unzip it. The zip already holds a saved copy of the data. - Serve it: open a terminal in the unzipped folder and run
python3 -m http.server 8177 --directory site(Windows:pyinstead ofpython3). - Open
http://localhost:8177in the browser. After that first visit it starts again with the server stopped.
The whole guide, with a school server, a USB stick and what works with no network, is docs/RUN_LOCALLY.md. The saved data is as old as the day the zip was made, and every card says so: tell the class that a satellite's position drifts after a week or two.
Present mode
One trip for a room: the panels go, each stop's words are set large enough to read from the back, and whoever holds the clicker decides when to go on. Add &present=1 to a trip's link, or press Present on the trip's first card; present=auto lets it move on by itself.
http://localhost:8177/#trip=moon-phases&present=1
http://localhost:8177/#trip=mars-where-we-have-driven&present=auto| Key | What it does |
|---|---|
→ Page Down Space | Next stop (a presenter's clicker sends these) |
← Page Up | Previous stop |
F | Full screen, and out of it |
A | Move on by itself, or wait for you again |
P | Pause and resume |
M V | Sound on and off; the voice on and off |
Esc | Leave the trip |
A screen nobody is standing at: the kiosk
For a corridor, a lobby, a museum wall or an observatory's waiting room, add #ambient=1 to the address and Space Radar plays its trips one after another, with the words of each stop as captions, until somebody takes the controls (any key or touch; two minutes after the last one it goes back to its reel).
| Address | What plays | One lap |
|---|---|---|
#ambient=classroom-45 | A lesson's worth: Twelve school favourites, from the living Earth to the edge of what we can see. | about 45 min, 12 trips |
#ambient=lobby | For a lobby or a corridor: The most visual trips, good with no sound, round and round for as long as it is on. | about 50 min, 14 trips |
#ambient=tonight | Tonight, from here: The trips that start from your own ground, for an evening at an observatory. | about 20 min, 7 trips |
#ambient=moon-landings,the-sun-today,black-holes | Your own list of trips, in your order |
Add to the address (each key is read by the app's own link reader):
| Parameter | What it does |
|---|---|
&shuffle=1 | A new order every lap |
&sound=1 | Ask for sound (a browser needs one key press); &sound=0 keeps it silent |
&voice=0 | Music only: no narrator |
&captions=0 | No words on screen (only sensible with the voice on) |
#autopilot= | The same key as #ambient=, under another name |
Start Chrome as a kiosk (quit it completely first):
chrome --kiosk --no-first-run --autoplay-policy=no-user-gesture-required "http://localhost:8177/#ambient=lobby"--kiosk is full screen with no address bar. --autoplay-policy=no-user-gesture-required lets sound start with nobody there; leave it out for a silent screen. The program is chrome.exe on Windows, /Applications/Google Chrome.app/Contents/MacOS/Google Chrome on a Mac, and chromium on Linux. A stop that fails to arrive is skipped, a trip that fails twice is left for the next, and the page reloads itself after twelve hours between two trips.
Five ten-minute lesson starters
Each pairs a question with one trip, started in present mode.
1. Why the Moon changes shape
Ask: where do you think the shadow on the Moon comes from? Then fly the trip and watch the Moon's month from space, then from your street. Stop on each phase and ask which way the Sun is. Finish by asking what a person standing on the Moon would see of the Earth in each phase.
2. How long is a year on another world?
Ask: how long does the Earth take to go round the Sun? Run a year in a minute and count how many times each inner planet laps the Earth. Ask whose year is shortest and why a planet closer to the Sun moves faster.
3. How big is the Solar System?
Ask for a guess in minutes of travel at the speed of light to the Sun, to Jupiter, to Neptune. Fly out past Jupiter and compare the guesses with the distances on each card.
Start the trip in present mode: Out past Jupiter, to the farthest thing we sent
4. How do we know planets of other stars exist?
Ask what you would need to see to know a planet is there if the star is far too bright. Fly to the planets of other stars and, at each card, ask which numbers are measured and which the picture only imagines (the pictures are artists' impressions).
5. What is orbiting above our heads?
Ask how many things are in orbit. Fly the trip from the working satellites to the ring that stands still and the junk, and ask what it would take to keep orbits tidy.
Accessibility
- Every control can be reached and used from the keyboard, with a visible focus ring, and every control has a name a screen reader announces.
- Touch targets are at least 44 px on a phone or tablet.
- The words of every trip stop are on screen as captions, so a room does not need sound; the narrator can be turned off.
- Motion calms when the system asks for reduced motion (
prefers-reduced-motion). - The 3D scene is a canvas and is not described to a screen reader; the cards and trip words beside it are text. Say so to a student who relies on one, and tell us what would help.
Tell us how it went
A lesson, a museum screen, a club night: tell us how it went on the project's GitHub (a short form: what you did, what worked, what did not). It is how this page gets better.