Article
For sixty years the default satellite has been a box with solar wings. The reasons are practical, but missions are changing, and the shape is changing with them.
Why boxes won
A box is the easiest spacecraft to build. Flat panels make simple mounting surfaces for electronics, star trackers and thrusters. Equipment can be tested panel by panel and assembled like a cabinet. Deployable solar arrays fold flat against the sides for launch and swing out in orbit.
Standards reinforced the habit. The CubeSat, introduced in 1999, defined small satellites in 10 cm cubic units, and a whole supply chain grew up around rectangular parts, dispensers and rails. Heritage matters in space: a shape that has flown hundreds of times is a shape customers trust.
What the box costs
The box's weakness is surface area. For a given volume, a cube has the smallest outside area of any rectangular shape, and only one face points at the Sun at a time. Power therefore depends on deployable wings, which add mechanisms, mass and failure points.
A box also has no preferred axis to spin about, so it relies entirely on active control to hold attitude. And in very low orbit, where there is still thin atmosphere, a box presents a large face to the airflow whichever way it points.
What's changing
Three trends are pushing designers away from the box. Payloads want more power: modern sensors, onboard processing and electric propulsion all draw kilowatts rather than watts. Launch has become a volume business, with rideshare and constellation missions packing many spacecraft into each fairing. And defence users want to fly lower, in very low Earth orbit, for sharper imagery and faster links.
Large broadband constellations already use flat-panel satellites that stack in the fairing. The next step is to rethink the shape completely.
Enter the disc
A disc answers each problem with geometry. Its upper face is a large, continuous surface for solar cells and antennas. It spins stably about its central axis. Flown edge-on, it slips through the upper atmosphere with little drag. And discs stack efficiently for launch.
The idea has now flown. In December 2025, four DiskSat spacecraft, flat discs about a metre across built by The Aerospace Corporation with NASA and US Space Force support, launched on a Rocket Lab Electron and demonstrated power generation, electric propulsion and formation flying.
What it means
The box will not disappear, but it is no longer the only answer. For missions that value power, aperture, low drag and launch efficiency, the saucer-shaped satellite is becoming a serious option.
OrbitalX's HALO takes the disc to a larger, defence-grade platform: a lens-shaped body with a shielded core, modular payload bays, metamaterial surfaces and electric propulsion.
Sources: NASA, DiskSat; The Aerospace Corporation, DiskSat.
Keep reading
What they are, why the shape works, real examples from DiskSat to HALO, and what they're used for.
Why are satellites boxes?The practical reasons behind the box, what it costs, and why disc designs are now reaching orbit.
Very low Earth orbit, explainedWhy defence satellites want to fly lower, the drag problem, and how a saucer shape helps.
See HALO's saucer-shaped design
Explore how the platform turns geometry into mission advantage.