As the number of satellites and other objects orbiting the Earth grew, and other nations began to launch increasingly sophisticated satellites and spacecraft into orbit, the U.S. Department of Defense (DoD) realized it needed a better way to identify objects in space and determine if they were threats.

To meet this requirement, in 2010, the DoD successfully launched the first satellites in its Space Based Space Surveillance (SBSS) system. This system has a mission similar to that of the Earth Observation (EO) satellites operated by the military, but with one major difference—instead of surveilling the Earth from space; it was designed to surveil space from space.

The SBSS is just one example of what was once known as Satellite Squared, but is now more commonly known as Non-Earth Imaging (NEI).

According to Stephen Hanna, the NEI Product Manager at Maxar Technologies, “NEI [includes] any image that a satellite captures that’s not of the earth, [such as] other satellites, space debris, spacecraft like the International Space Station, the moon, or even asteroids that can pass close to Earth.”

While the term “NEI” may not be familiar to everyone, Hanna explained that the capability of taking satellite imagery of objects in space, “…has been around since the advent of imaging satellites…” However, while it might not be a new concept, NEI has long been a government and military capability.

In just the past half-decade, a new generation of NEI providers has emerged, each offering the ability to take quality images of objects in space. What opened the door for these commercial NEI providers, what role does NEI play in the larger Space Domain Awareness (SDA) picture, and why is this service so important for today’s satellite industry?

Changing regulations and automation

While new and innovative technologies have played a role in enabling the development of commercial NEI, few advancements have been as critical to its growth and success as the regulatory changes that made it possible.

“NEI is a relatively new phenomenon from a commercial standpoint because NEI was heavily restricted in the U.S.,” explained Hilary Cohen, the Director of Operations at commercial NEI provider, HEO. “A U.S.-based commercial company could not do NEI because of national security concerns.”

However, this all began to change just a few years ago. According to Hanna, “[In 2023] NOAA lifted many commercial remote sensing license conditions, which included restrictions to NEI, which opened it up for other commercial companies.”

While regulatory changes have opened the door to commercial NEI operators, new technologies have also made commercial NEI solutions effective and economically viable. This includes advancements in spacecraft and imaging payloads, and the creation of new software solutions capable of meeting the rigorous requirements for imaging fast-moving objects in space.

“From a technology standpoint, it’s really hard to take an image of a satellite in space because of how fast things are moving - especially in Low Earth Orbit (LEO),” said Cohen. “Figuring out where the object is in space relative to where the cameras are positioned, and identifying that one split second when you can take that image is incredibly difficult.”

This is a challenge that NEI providers are solving with the help of software. As Cohen explained, “Manually calculating the opportunity [for imaging an object] could take months…software automates that tasking…”

The confluence of changing regulations and new innovations has made it possible to offer NEI capabilities to government and commercial customers today. And the timing couldn’t be better.

A capability for our times

With mega-constellations like Starlink, Kuiper, and China’s G60 being deployed, some orbits, including LEO and GEO, are becoming incredibly congested. At the same time, some global militaries have demonstrated the ability to physically degrade or destroy satellites in orbit.

“Since the end of 2015, China’s on-orbit presence has grown by approximately 550 percent. As of March 2024, China had more than 950 satellites in orbit, about 470 of which were ISR-capable satellites,” said Hanna. “Russia has also deployed several anti-satellite prototypes in LEO with the potential to launch more. [The space domain] is now more congested AND contested.”

NEI is a complementary piece of a larger puzzle that can help solve many of the problems that satellite operators face in this more congested and contested space domain. One of those challenges is SDA.

As the number of objects—from satellites to spacecraft to space debris—continues to skyrocket, the risk posed by those objects increases. Understanding where objects in orbit are located, what they are, and how they behave is becoming increasingly essential to better understanding the risk they may pose to military and commercial satellites in orbit.

Delivering a more detailed SDA picture

Historically, SDA requirements have been met with terrestrially based telescope and radar solutions. Both have limitations, however, in terms of the nature of the data they can provide, how far they can “see,” and challenges with environmental obstructions such as weather or darkness.

More recently, companies leveraging passive and active RF signal scanners, companies like Kratos and Spire, have helped their customers identify where objects in space are positioned. These solutions also provide valuable information about the operation, health, location of origin, behavior, movement, and other details about objects in space.

“Radar would be considered an active RF sensor. A signal is sent out, it bounces off the satellite, and then comes back – which shows the location of the satellite. Passive RF sensing identifies a satellite’s location based on the signals the satellite is transmitting, or signals coming from the ground from other sources that are bouncing off the satellite,” said Hugh White, a Senior Director of Space Domain Awareness Solutions at Kratos, which operates a global, earth-based network of RF sensors. “Both provide a wealth of additional information for locating and tracking ’live’ objects in space, such as satellites.”

Spire, on other hand, is working to implement what they call “RFGEOINT” capabilities - RF scanning solutions that utilize sensors on satellites in orbit.

“There are areas where RF scanners do not exist, including wide swaths of the ocean and certain terrestrial areas where we can’t place ground stations,” explained Evan Staresinic, a Business Operations Manager at Spire Federal. “RFGEOINT functions to address the gaps in RF and radar services that exist today.”

Government and commercial organizations collect and fuse all these different types of data to form an awareness picture as rich and complete as possible. However, sometimes, the situation or mission calls for a picture. And that’s where NEI can play a complementary role to other SDA solutions - answering questions about the identity of objects in space that other SDA solutions cannot.

“We’re tracking the dots with RF and other SDA capabilities on the ground, but there are still more than 500 unidentified objects floating around,” said Cohen. “[RF and radar scanning] can tell us whether or not they’re receiving or emitting signals, but we [may not know] what they are, where they came from, or what their intended missions are. We can image them and close that uncertainty gap.”

Other use cases for NEI

NEI is capable of providing insights into more than just unidentified spacecraft. These solutions could also be used by satellite operators to get answers and information about their own satellites. Should a satellite begin to malfunction or be involved in a collision in space, NEI solutions can help to identify whether any damage was done or what the problem might be.

“If I am a [satellite] owner-operator, and a piece of debris hits my satellite or my satellite isn’t working, I may want someone to take a picture of my satellite so I can see exactly what the state is and figure out a course of action moving forward,” said White. “If I’ve had some sort of anomaly and I’m not getting what I expect from my satellite, it’s really useful to have somebody else take a picture of it up close for me.”

This capability can’t be met with terrestrial imaging solutions due to limitations in quality and the sheer distance from the subject. According to White, “[With] a telescope on the ground—I don’t know whether you’ve gotten to see the types of pictures that they produce—but they’re generally very low resolution.”

Finally, NEI capabilities could play a large role in future space and satellite capabilities that are just starting to be developed and deployed. This includes satellite refueling and the deorbiting of space debris. Using NEI can be instrumental in pre-mission planning, giving key stakeholders essential information about the status of the objects that they’ll be interacting with and the conditions that they’ll face.

“…when [operators are] doing their mission planning to either refuel an object or grab an object during debris mitigation missions, we can actually help de-risk that early on by taking pictures of the object,” said Cohen.

The same capability could play a role in future missions where satellites and spacecraft could be physically manufactured in space. “…it’s not just approaching and co-orbiting something, it’s also about manufacturing things as you’re flying,” said Hanna. “In the future, especially when it comes to commercial space operations, new space stations are just not efficient or sustainable to launch. It’s more efficient to build them in orbit. That is where we’re going.”

With restrictions lifted and new technologies automating the difficult task of imaging rapidly moving objects in space, commercial NEI solutions are taking off. The use cases for NEI are already numerous and growing, as the need to identify unknown objects in space, diagnose problems with satellites, and deliver high-fidelity imagery for space domain awareness only increases.

“Before, it used to be that you’d launch a satellite into space and never see what it looks like again,” said Cohen. We’re changing that. And it’s not just an idea. Commercial NEI is here. It’s available.”

Explore More:

Opening Eyes: Small Businesses Tackle Space Domain Awareness

What Can We Learn About Space Age Conflicts by Watching Signals?

Podcast: Tracking LEOs, Growth in Resident Space Objects and the Problem with Uncertainty