Today in space

Reading the live feeds…

·Kp, of 9
·Potentially hazardous
·LDClosest pass
·Earth events

Space weather

·Kp, of 9

Solar wind: ·
Radio blackouts: R·
Geomagnetic storm: G·

Earth events

All events in the Earth view

Engine

A real-time orbital engine, written from scratch in Rust and run on your graphics card through WebGPU.

Measure	Value	Method and source
Download	221 kB	WebAssembly over the wire, Brotli, measured on the live deploy (551 kB unpacked)
Frame rate	60 fps at 50,000 and at 1,000,000	Apple M2, Chrome 153, 2026-09-29 (PERFORMANCE.md)
GPU time to move orbits	0.1 ms at 50,000, under 1 ms at 1,000,000	WebGPU timestamp queries on the compute pass, rounded to 0.1 ms, same machine and date
CPU per orbit	none	a compute shader moves every object (src/shaders/compute_physics.wgsl)
Draw calls	1 for all satellites	one indirect draw after a GPU cull (src/gpu/render.rs)
Real objects	·

What it is

A real-time graphics engine written from scratch in Rust, compiled to WebAssembly and driving WebGPU directly. No Three.js, no game engine, no scene graph.

Tens of thousands of satellites in four orbital shells, moved on the GPU at 128 times real time by default. The real ones come from the CelesTrak catalogue; the rest are generated to fill the scene. A simplified Kepler model with J2 drift moves them, so this is not a live tracker. The NASA and NOAA data around it is live. Your browser asks wheretheiss.at for the ISS position directly.

How it works

Every frame, a compute shader advances each satellite on its orbit, and the render pass reads the positions straight from GPU memory, so the CPU never touches an object. One indirect draw call covers every satellite. When nothing moves, an idle gate stops the GPU work.

Why it holds up

On an Apple computer in Chrome 153 (2026-09-29) the scene held 60 frames per second at 50,000 objects and at 1,000,000. The GPU moved 50,000 objects in 0.1 ms per frame and 1,000,000 in under 1 ms, measured with timestamp queries.

Credits

Planet and Sun textures: Solar System Scope (solarsystemscope.com), CC-BY 4.0. Earth albedo: NASA Visible Earth, public domain.

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Built by Tenzan Logic

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Orbits ·

LEO below 2,000 km · MEO up to 35,800 km · GEO at 35,800 km · Molniya: long, tilted ellipses

Asteroids

Passing this week: ·
Potentially hazardous: ·

Closest pass ·

Nearest first, in lunar distances (LD)

Close approaches

Pairs of objects in the scene, generated ones included, passing within 25 km of each other, checked on the graphics card twice a second. A screening, not a forecast: the model has no error estimate, so a distance here is a sketch.

In sunlight: ·
ISS model against live fix: ·

Passes over you

Ground site

Choose a ground site to see passes over it.

ISS

About the engine

Every dot is an orbit computed on your graphics card by an engine written from scratch in Rust and WebGPU. A stylised picture of Earth’s orbit, not a live tracker; the NASA and NOAA data around it is live.

Open the Engine view4

AstrOS Real-time orbits, Rust + WebGPU

Engine now

System and data

Pictures

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Lists

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