Primer

Volume X · 02 · Light

02 · The bet

Light

c is 3×10⁸ m/s. LEO is a few milliseconds. GEO is a quarter-second round trip before routing. The speed of light does not negotiate.

In English

Radio and laser still travel at c. Up and down to 550 km is a few milliseconds. Up and down to GEO is ~240 ms before anyone routes a packet. That floor is physics.

Try this
Ping LEO, then GEO. Watch the dot. Read RTT.
Keep this
LEO ping is terrestrial-ish. GEO ping is a satellite.

Lab · ping the sky

Light is 3×10⁸ m/s. LEO is a short hop. GEO is a long one. Routing, processing, and a bent-pipe double-hop make the real ping worse. The floor is this cartoon.

One-way 23.1 ms · RTT 46.2 ms

One-way time is range/c. GEO range ≈ 36 000 km plus a bit of slant; 120 ms one-way, 240 ms RTT. LEO 550 km is ~2 ms one-way before elevation and routing.

Bent-pipe GEO doubles the hop. Inter-satellite lasers on LEO can walk the mesh without another ground bounce. Processing delay still sits on top of c.