Orbits

Visualizing different types of orbits

I spent more time improving the TLE tool I built, and used it to learn more about Geocentric orbits. I basically plugged in TLEs from CelesTrack into the tool to generate images below. I also found this amazing SVG on Wikipedia, which is a good overview. It’s clickable, so you can use it to learn more about the information depicted.

Most artificial satellites are in Low Earth orbit, including the ISS and Starlink constellation. The altitude of objects in this orbit is never more than about one-third of the radius of Earth (roughly 2,000 km).

Medium Earth orbit encompasses altitudes between 2,000 km and 35,786 km above sea level. The GPS constellation is located in MEO, specifically in Semi-synchronous orbit, at an altitude of roughly 20,000 km.

Objects in Geosynchronous orbit are at an altitude of 35,786 km and their period equals one sidereal day, coinciding with Earth’s rotation period.

Satellites in High Earth orbit have an altitude entirely above that of a Geosynchronous orbit. They appear to be in retrograde motion, since their orbital period is greater than 24 hours.

A satellite in Polar orbit passes above or nearly above Earth’s poles on each revolution.

Satellites in Molniya orbit spend most of their time over a designated area of the Earth. Molniya is a highly elliptical orbit.

There’s a lot more details on this, Wikipedia is an amazing resource as usual. Links above are a great way to get started.