# Satellite internet

> Internet access beamed from space to a dish, where cables and cell towers don't reach.

- Level: Basic
- Topics: Networks
- URL: https://tidbit.legios.com.ar/satellite-internet/
- In Spanish: [Internet satelital](https://tidbit.legios.com.ar/es/satellite-internet/)

**Satellite internet** connects a home, a ship or a plane to the internet without any cable running to it. A small dish or flat antenna points at the sky and exchanges radio signals with a satellite. The satellite relays them to a **ground station**, a site with big antennas that is plugged into the regular internet. Everything you send and receive makes that trip up and down.

For decades the satellites sat in **geostationary orbit**, roughly 36,000 km up, where one satellite seems fixed in the sky and covers a third of the planet. The catch is distance: the signal takes roughly half a second to go up, down, and back again, so video calls feel awkward and online games are nearly unplayable, even when downloads are reasonably fast.

Newer systems use thousands of smaller satellites in **low Earth orbit**, a few hundred to about two thousand kilometers up. Being closer, they cut the delay, the latency, to something similar to a regular home connection. Because each one crosses the sky in minutes, the dish keeps handing your connection from one satellite to the next. SpaceX's Starlink is the best-known example; others are being built.

It is a lifeline for rural areas, islands, boats, flights and places where a disaster knocked out the ground network. The trade-offs: the dish needs a clear view of the sky, heavy rain or snow can weaken the signal, and capacity is shared among everyone under the same patch of sky. Large constellations also raise concerns about space debris and about streaks across astronomers' images.

## An analogy

Shouting to a friend across a valley by bouncing your voice off a mountain. A distant mountain carries it far but the echo comes back late; a closer hill answers quickly, but you need many hills to cover the whole valley.

## Keep in mind

- A dish talks to a satellite, which relays to a ground station on the internet.
- High geostationary satellites add roughly half a second of delay.
- Low-orbit constellations use thousands of satellites to cut that delay.
- Needs a clear view of the sky; heavy weather can slow it down.

## Go deeper

- [Satellite internet access on Wikipedia](https://en.wikipedia.org/wiki/Satellite_Internet_access)
- [Low Earth orbit on Wikipedia](https://en.wikipedia.org/wiki/Low_Earth_orbit)
- [Geostationary orbit on Wikipedia](https://en.wikipedia.org/wiki/Geostationary_orbit)

## Related terms

- [Internet](https://tidbit.legios.com.ar/internet/): A worldwide network of networks that lets any connected device reach any other.
- [Bandwidth and latency](https://tidbit.legios.com.ar/bandwidth-and-latency/): How much data fits per second, and how long each trip takes. Two different things.