Hours after the news broke on Wednesday that the United States had picked up worrisome intelligence about Russia’s capacity to strike American satellites, the Pentagon sent a missile-tracking system into orbit, part of a vast new effort to bolster the military’s growing presence in space.
The timing was coincidental. But it underscored how concerns about advances in Russian and Chinese capabilities in space have led the United States to embrace innovative ways of protecting vital communications, surveillance and GPS systems on the battlefield of the future.
The system put into orbit on Wednesday was a prototype developed to test a new plan, named Proliferated Warfighter Space Architecture, that aims to blanket low-Earth orbit with hundreds of smaller, cheaper satellites. The approach is like a version of the Starlink internet communications system that Elon Musk’s SpaceX already has in orbit, with more than 5,000 satellites. (The Pentagon prototype on Wednesday was launched on a Space X rocket.)
The idea is that even if enemies of the United States could knock out some of its satellites — or even more than a dozen of them — the system could keep operating by shifting to other units in the orbiting web.
“For a long time, you could count our space constellations by the handful — satellites the size of school buses that took decades to buy and build, years to launch,” Kathleen H. Hicks, the deputy defense secretary, said last month at U.S. Space Command, which is responsible for coordinating the Pentagon’s military operations in space.
But now, she said, the United States is shifting to “proliferated constellations of smaller, resilient, lower-cost satellites” that can “launch almost weekly.”
Officials in Washington have realized in recent years that one of the first moves the United States would likely face in any major war with China or Russia would be an attempt to disable United States telecommunications, geolocation and surveillance systems in space.
That is what the new intelligence suggests Russia may be planning with its new space-based weapon, the subject of a briefing from senior national security officials to congressional leaders on Thursday.
Right now, most American military satellite systems are extremely vulnerable to such an attack because they are very small in number and very large. When first built, they were considered unlikely targets for any U.S. enemy, except during a nuclear war.
The constant surveillance of the world that they provide has become one of the United States’ most important military advantages. The Pentagon can not only track major missile threats, it also can use its system to communicate among the branches of the military and send targeting information to its own weapons, while providing instant information about enemy troop or equipment movements.
The war in Ukraine has shown how vital these tools are. Relying in part on U.S. satellite imagery provided by private companies, Ukraine has been able to track Russian movements more closely than technology would have allowed in any previous war and maintain its communications systems despite Russian efforts to jam them.
Commercial satellites are also a critical part of the U.S. economy, providing everything from GPS to the communications systems used by thousands of companies from banks to gas stations.
“If I were on the general staff of Russia, or if I was serving in the P.L.A., I would be advising the leadership to go after the space capabilities of the United States,” Lt. Gen. John Shaw, who until recently served as deputy commander of U.S. Space Command, said at an Air Force conference in Colorado last year, referring to the People’s Liberation Army of China.
The United States relies on satellites “to project power across the planet, and they’re not all that well defended,” General Shaw said. “So we should not be surprised they were under threat.”
The Pentagon’s Space Development Agency is budgeting nearly $14 billion in the coming five years to build out the new system, budget documents show, though delays by Congress in approving a 2024 budget could slow the timeline, Pentagon officials said. The agency is in charge of buying the new satellites and paying for the launches to get them into low-Earth orbit for missile warning and tracking and further research, prototypes and deployment of new space-based weapons.
Right now, the Pentagon, like NASA, is relying heavily on Mr. Musk and SpaceX to put these new satellites in space. A SpaceX Falcon 9 rocket lifted off on Wednesday evening from Cape Canaveral in Florida that carried the two prototype Pentagon satellites that will be tested over the next two years.
The satellites launched on Wednesday — they are called Hypersonic and Ballistic Tracking Space Sensors or H.B.T.S.S. — are intended to help detect missiles that might be launched by China, Russia or some other nation, giving the United States a better chance to intercept and destroy them sooner.
“These H.B.T.S.S. satellites are an essential step forward in our efforts to stay ahead of our adversaries,” Lt. Gen. Heath Collins of the Pentagon’s Missile Defense Agency said in a statement before the launch.
Contracts for other small, low-Earth-orbit systems have already been granted to major military suppliers like Lockheed Martin and Northrop Grumman. But the Pentagon is also working with start-up companies that are focusing on the space market, such as Rocket Lab and Sierra Space, which in January announced a Pentagon contract worth up to $740 million for 18 warning and tracking satellites, the largest in its history.
The Pentagon is separately looking to hire new launch companies that will be able to take orders from the military and rapidly put a new satellite system in space. In September, Firefly Aerospace put a military space vehicle into orbit from California just 27 hours after receiving launch orders. The previous record was 21 days.
This kind of rapid turnaround could allow the United States to put up new satellites quickly if existing ones are destroyed during a conflict. It also could be vital in any major global conflict, Air Force Secretary Frank Kendall said in an interview.
“We’re not going to be able operate in the Western Pacific successfully unless we can defeat those,” he said last month, referring to new Chinese and Russian antisatellite systems.
Todd Harrison, an aerospace engineer and space security scholar at American Enterprise Institute, said that by the end of the decade, the Pentagon will likely have 1,000 new satellites in low-Earth orbit, which is less than 1,200 miles from the surface.
Older Pentagon and spy satellites have typically been much farther out in so-called geosynchronous orbit, about 22,000 miles above Earth. From that vantage point, satellites can see more of the Earth at once, but their signals take longer to reach the surface. That would make it harder to use them in advanced, artificial-intelligence-based weapons systems that might be making targeting decisions on their own and almost instantly.
China has been moving quickly in recent years to build its own weapons that could be launched from the ground to hit American satellites in orbit or stationed in space. It has already tested satellites that have arms that can reach out and grab or trap other satellites, capacity the United States also has but so far has used only for peaceful purposes.
Chief Master Sergeant Ron Lerch, an intelligence analyst with the U.S. Space Force, said China is on its way to building its own constellation of as many as 13,000 satellites for communications and military needs. That is in addition to other advanced tools such synthetic-aperture radar, which can use radio waves to track military movements even at night and beneath cloud cover.
“Where China is going now, they completely dwarf the Russians in terms of intelligence, surveillance, reconnaissance” from space, he said during a Space Force conference in Florida last month.
The United States is already moving to add capabilities to the new satellites it is launching, so they can be refueled in space and move while in orbit if necessary, as part of a plan to extend their life and if necessary defend themselves.
The United States has its own Earth-based missiles that could target enemy satellites in space or send radio signals that disrupt them. But so far it has not acknowledged in public that it has offensive weapons in space, Mr. Harrison said.
“We are designing a future space architecture that will be much less vulnerable,” Mr. Harrison said. “Our economic and military security is now heavily dependent on space.”
