VANDENBERG SPACE FORCE BASE, Calif., July 14 — The figure that matters: 47,000. That is the number of objects the U.S. Space Force currently catalogs in orbit, according to Space-Track.org. The bottom line: the military branch responsible for protecting American assets in space cannot see everything up there.
By the numbers, the Space Surveillance Network, operated by the 18th Space Defense Squadron at Vandenberg, tracks objects larger than 10 centimeters in low Earth orbit and objects larger than one meter in geosynchronous orbit. But a debris swarm discovered in GEO in 2024 includes objects as small as 0.1 meters — well below the network’s detection threshold.
The Space Force became the sixth branch of the U.S. Armed Forces on December 20, 2019. Its core mission includes space domain awareness, which means tracking both active satellites and the growing cloud of orbital debris that threatens them. Investors will note the budget figure: approximately $1.5 billion for space domain awareness in fiscal year 2024, per the Department of Defense.
That money funds a global system of radars and optical telescopes known as the Space Surveillance Network, or SSN.
The Detection Gap
The SSN has a hard limit. It cannot track objects smaller than 10 cm in LEO or smaller than one meter in GEO. The newly reported debris swarm in GEO, with fragments as small as 0.1 meters, simply does not appear on the network’s screens.
In 2023, the Space Force issued over 10,000 conjunction warnings — alerts that two objects might collide. Each warning represents a potential threat to a satellite.
As debris populations grow, those warnings will only increase. To close this detection gap, the Space Force deployed Space Fence. This ground-based radar system on the Kwajalein Atoll in the Marshall Islands became operational in 2020.
Space Fence can detect objects as small as one centimeter in low Earth orbit — an improvement over the SSN’s LEO capability.
Commercial Partners
The Space Force does not work alone. It collaborates with commercial entities like LeoLabs, founded in 2016, which operates its own network of phased-array radars. These private systems add additional eyes on the orbital environment.
The U.S. government provides collision avoidance services to satellite operators worldwide, not just American ones. When a conjunction warning issues, operators can decide whether to maneuver their spacecraft to avoid a potential impact.
The bottom line for satellite operators: the Space Force sees the big pieces, but the small ones — down to one centimeter in LEO via Space Fence — remain the frontier. The GEO debris swarm, with objects at 0.1 meters, falls into a blind spot no current system covers. What to watch next: how the Space Force integrates Space Fence data with commercial radar feeds, and whether budget allocations for space domain awareness increase to address the growing debris problem in geosynchronous orbit.
