Orbit Fab will soon launch fuel depots for satellites in geostationary orbit and even offer self-driving refueling services. Price? 20 million dollars for 100 kilograms of hydrazine (a chemical compound for the engine). Much cheaper than developing and launching a new geostationary satellite.

What does geostationary orbit mean?

Geostationary satellites are those that appear to always be above a fixed point above the Earth (they actually orbit the Earth like any other satellite, but do so at the same speed as the Earth rotates on its axis). This is particularly useful for telecommunications satellites (which provide TV, radio or even Internet services, but unlike Starlink, they do so with a much longer delay). To reach the speed required for such an orbit, geostationary satellites are 35,786 km above the Earth’s surface, which is much further than low-orbit satellites (only a few hundred kilometers).

Reaching this height typically requires a high-performance launch vehicle, as well as an upper stage that can restart its engine in space to send the satellite to a higher altitude, meaning a higher cost to launch a satellite into geostationary orbit compared to satellites placed in low Earth orbit.

Moreover, maintaining visibility over a fixed point is accomplished by small orbital adjustments, maneuvers that consume the satellite’s fuel. And when the fuel reserves are exhausted, the satellite is placed in a special orbit so as not to interfere with other operating satellites.

Thus, if these satellites could be refueled, their lifetime could be significantly extended, which not only means lower costs for the operator (who no longer needs to launch a new satellite or develop a new satellite), but it also reduces orbital pollution by reducing the number of secondary stages or the number of inactive satellites.

Orbit Fab plan

Orbit Fab became famous a few years ago after developing a special valve (called RAFTI) that can be used both on the ground and in space to refuel specific satellites. Now he wants to expand his reach and build fuel depots that he can place near geostationary orbit (300 km above the altitude used by telecommunications satellites) from where he can refuel satellites that are running out of fuel and do so with his vehicle. its own, which would dock with the stranded satellite and transfer fuel to it.

The problem is that almost none of the more than 400 satellites in geostationary orbit have a RAFTI valve that can be used to pump fuel (hydrazine, since the engines on board telecom satellites typically use this chemical for propulsion). But Orbit Fab has a solution to this problem.

MEV – Mission Expansion Vehicle

In 2019, a small MEV-1 (Mission Extension Vehicle) satellite, created by the American company Northrop Grumman, was on board the Russian Proton-M launch vehicle. After separation from the additional stage of the Proton launch vehicle, the MEV-1 launched towards the Intelsat-901 telecommunications satellite. Launched in 2001, it was nearing the end of its life and had already been removed from its nominal orbit, but MEV-1 docked with the Intelsat-901 satellite and, using on-board fuel, returned it to a place from where it could be used again. The Intelsat-901 satellite is expected to be operational until 2025.

MEV-2 was launched in 2020 by a European Ariane 5 rocket, and a few months later it docked with the Intelsat 10-02 satellite, which also significantly extended its life. MEV satellites are small and were launched as auxiliary payloads, so their launch does not create orbital debris because they still share the path to orbit with other, larger satellites.

So it’s no surprise that Orbit Fab is already in talks with Northrop Grumman about a collaboration where the MEV vehicles used to dock with geostationary satellites will be equipped with a RAFTI valve that will allow fuel to be transported from future geostationary depots. That’s because other MEV vehicles will be launched in the future, and they fit nicely into Orbit Fab’s plan, at least until there are geostationary satellites equipped with this fuel transfer valve.

Depending on size and performance, a geostationary satellite costs anywhere from $150 million to $500 million, including launch. Under these conditions, $20 million per 100 kilograms of hydrazine, an amount that significantly extends the life of a satellite, becomes an attractive sum for geostationary satellite operators.