[geertj]

The always on orbit exists and is called a dawn-dusk Sun synchronous orbit. It is an orbit that is always above the terminator (line between night and day) where it can face the Sun 100% of the time.

This orbit has to rotate about a degree every day to follow the terminator as the earth orbits the Sun. It uses the equatorial bulge of the earth to achieve that rotation without have to spend rocket fuel. It is really quite interesting.

[adrian_b]

But the slots on such Sun-synchronous orbits are limited and many applications want them.

A few datacenters could occupy some slots, but it would be difficult to accept a large number of datacenters obstructing such orbits.

[saalweachter]

Aren't dusk-dawn orbits already the most crowded orbital space with the most orbital debris?

[geertj]

Yes they are crowded. There are engineering solutions to that, including formation flying based on absolute positioning and space tethers. It is a great time to be an engineer.