Have you planned out exactly how you will de-orbit a satellite as part of any upcoming mission?
Minimizing risks to other space assets and operations is becoming an increasingly important factor for any new mission and a clear and timely de-orbiting plan is a crucial element of this.
There are also a growing number of active and passive de-orbiting systems and propulsion technologies available on the market to help with the process of moving a satellite into a graveyard orbit at the end of its operational life.
But in order to select the most suitable system to work with your hardware, software, and mission plan, you need to weigh up a number of factors beyond the available Size, Weight, Power, and Cost (SWAP-C) budget. Let’s take a closer look:
Operating orbit
The higher the orbit, the harder it is to de-orbit, and the longer it will take. This is because hardware systems operating in the higher orbits are (usually) larger, obviously further from Earth’s graveyard orbit, and often have more complex mission plans with longer operating lifetimes. There is also less traffic and debris the further you get from the planet, which also has an effect on the rules in place.
Because of this, regulations and guidance can differ for orbits further from Earth and some technical solutions may not be suitable for hardware of such high masses.
There’s more technical information on the practicalities of de-orbiting processes in NASA’s State-of-the-Art of Small Spacecraft Technology, but the takeaway message is that the operating orbit (or orbits) of your spacecraft will be a major determining factor in the sort of de-orbiting guidelines you’ll need to follow, and the technologies available to do so.
National laws and regulations
Some countries have put in place regulations on de-orbiting timescales for space systems that fall under their jurisdiction (whether that’s for the entire mission or just for part of the operation).
For example, the Federal Communications Commission (FCC) regulates that systems designed to operate in Low Earth Orbit (LEO), and which are either US-licensed satellites or are LEO satellites from other countries that want to access the US market, must de-orbit within 5 years of the mission completion date.
Many such national regulations or recommendations are based on existing guidance frameworks, such as;
- The Inter-Agency Space Debris Coordination Committee guidelines
- The International Organization for Standardization (ISO) Space systems – Space debris mitigation requirements standard (ISO 24113:2010)
- The European Code of Conduct for Space Debris Mitigation [PDF]
It’s important to remember that regulation isn’t static. New rules come into force, and existing ones are altered, on a regular basis. So developing future mission plans might involve predicting how guidance could change and considering how this would affect your mission.
It might be safer, for example, to assume that de-orbiting requirements are only going to get stricter as debris and traffic volumes grow. However, it is also possible that industry dialogue, new innovations, and changing priorities at publicly-funded organizations result in less stringent options becoming available in certain circumstances.
For example, some satellite operators are arguing that waivers to the FCC’s 5-year rule should be available for qualifying missions. The FCC has also recently reorganized, opening a new Space Bureau and Office for International Affairs (OIA) to “modernize satellite regulations” at a national and global level – so further changes and nuances to the existing rules might be on the way in years to come.
It’s clearly vital to find out whether there are any national rules that relate to the territories in which you intend to operate, and determine how they affect your system, while understanding that they might evolve along the way. But that’s still not the whole picture.
Agency rules
A number of national and international space agencies have also produced de-orbiting guidelines. These are typically only applicable to missions and programs under the oversight of those agencies, so might not apply to a purely commercial service.
For example, NASA has a guideline in place specifying that any hardware in space must be limited to a maximum orbital lifetime of 25 years from the date of mission completion. You can read the full standard here [PDF].
This rule has already been enforced on a number of satellites. For example, a NASA CubeSat was removed from a U.S. Space Force mission launch in August 2022 – in this case, although the system had been built to meet the 25-year rule, a delay in the launch date meant that this deadline would have been missed!
On the other side of the pond, ESA have stated that they intend to put in place a new global guideline that would require satellites to begin de-orbiting immediately after the end of the mission.
The bottom line is; if your mission is part of a national or international agency’s program, certain de-orbiting requirements might apply, so be sure to take these into account as well as the relevant national legislation.
When does it all end!?
As you can see, a common aspect of many of the regulations and guidelines mentioned above is that they specify that the de-orbiting process must take place within a certain period that begins once the mission is completed. But definitions vary on when exactly that is.
A mission plan might specify a target operating lifetime, but there are many reasons why this might be different to the time the satellite is active in orbit. If a system needs to avoid collisions a number of times for example, it will use up propulsion propellant, shortening the lifetime.
On the other hand – a technology demonstration that goes better than expected could see a satellite remain operational for years longer than initially planned.
It is important to understand exactly what the de-orbiting guidance or regulation means when it says “the end of the mission” so you’re working to the right goal in the mission plan.
Conclusions
The decision of exactly when to de-orbit a satellite is clearly not straightforward and there are several variables to take into account.
In this article we’ve only discussed the regulatory aspect of this – there is also a brand perception element; demonstrating that your company is a responsible actor in the space environment.
It will be interesting to see how these discussions and regulations evolve alongside the development of new de-orbiting innovations in the marketplace.
If you would like some FREE expert guidance on developing a mission and procurement plan that takes de-orbiting into account – simply share your requirements with us here.