Now Entering Orbit: Tiny Lego-like Modular Satellites

Just about a year ago, SpaceX sent the rocketry equivalent of a clown car to space: A rocket crowded with more than 60 small satellites. Inside one of them, Excite, were even more. It was actually a satellite made of other satellites, all clones of each other, all capable of joining together and working together. It was one of the first in-space tests of such a contraption—but in the coming years, this modular approach is likely to show up on more and more missions.Excite was flung into space courtesy of a company called NovaWurks, which makes “satlets.” The suffix—like that of “piglets”—implies littleness, and indeed these 14 satlets are smaller than a standard piece of paper and only a few inches thick. Even at that size, they supply everything a satellite needs—a way to communicate with Earth, a way to move in space, a way to process data, and a source of power. You just hook your camera, radiation sensor, or computer circuit in before launch and then send the whole package to space. Each satlet, which NovaWurks calls a HISat, can also physically join up with others, forming one larger unit that shares resources.

On this launch day, liftoff was as perfect as a picture. Once the rocket soared to its appointed height, Excite entered its orbit. All seemed good, and most of the attached instruments—as well as the spacecraft itself—performed pretty much as expected. But Excite wasn’t able to send commands to some of the devices aboard. The spacecraft had technical difficulties connecting to some payloads, and three of the eight payloads plugged into the satlets couldn’t hear and obey their groundmasters.

Nonetheless, this failure has been seen as an acceptable bump along a very compelling road. Plug-and-play satellites are like the Konmari method transposed to space: They cost less money, they take less time, and because they let engineers focus on instruments rather than logistics, they spark more joy. Organizations like NASA, the Air Force, and the National Reconnaissance Office are all realizing they like that type of joy, and are pumping out contracts and programs that provide this new technology with a ride to orbit. And NovaWurks was one of the first companies to actually take the idea to space.
Darpa—the Department of Defense’s advanced R&D organization —got the modular party started early with a project called Phoenix . One of its goals, says program manager Todd Master, was to figure out whether it would be possible to combine small satellites into a larger one. Sort of like Legos, except rather than merely snapping them together, getting them to work together. In 2012, the agency started doing business with NovaWurks, which eventually became the prime contractor for that part of the project.

The great promise of satlets is that they are agnostic about what instruments they support and about what function they fulfill. They can be mass-produced, which both slashes costs and dents the idea that each new instrument to be sent into orbit requires a whole new satellite. Instead, you can buy a satlet (or 15) that will provide everything your camera, radar device, radio detector, infrared sensor, or data processor will need. In theory, the set can also fix itself after launch by reallocating resources: A group of linked satlets can share functions among themselves and adjust their effort based on changing needs. If a battery in one gets a bad cell, for instance, its partners can help out.

This approach makes sending stuff to space less risky, and potentially faster for developers, because they don’t need to build an entire satellite from scratch. Other companies plan to offer mass-produced satellite platforms . But few others can connect a set of them into one larger system, and make all the elements play together. With that particular pitch, NovaWurks won around 40 million Darpa dollars, and the partners jointly recruited parties to put payloads aboard.