On the eve of America's Independence Day celebration this year, the Chinese official news agency Xinhua carried a story detailing how Beijing intends to catch up with and surpass the most ambitious rocket program the U.S. has ever attempted. That program is NASA's Space Launch System (SLS), and it is frequently billed as the first step in a manned mission to Mars.
SLS initially will use a Boeing core stage powered by four Aerojet Rocketdyne liquid-fuel engines plus strap-on solid-fuel boosters made by Northrop Grumman to lift the Orion crew vessel far beyond where humans have previously ventured. Over time, the rocket will evolve to a larger size capable of lifting 130 metric tons into Low Earth Orbit, over twice the lifting capacity of SpaceX's recently launched Falcon Heavy rocket.
The principle mission of SLS, though, is not to get to Low Earth Orbit. It is designed to support deep space exploration, with an eye to one day visiting Mars -- the only other Earth-like planet in the solar system. However, China has announced no plans for going to Mars. So why does it want a rocket that can lift even more than SLS -- 140 metric tons to Low Earth Orbit, according to the senior official at the Chinese Academy of Engineering quoted in Xinhua's July 2 story?
I have a theory, or at least a suspicion. Unlike in the U.S., where military and civil space programs are managed by separate agencies, the Chinese space program is run mainly by the military. That arrangement is driven partly by economic considerations, but it also reflects the fact that rocket technology can be applied to ballistic missiles and satellites often have military uses. For instance, the People's Liberation Army would prefer not to rely on America's GPS constellation for navigation -- it wants its own positioning constellation.
But you don't need a super-heavy-lift rocket to loft positioning satellites into orbit. China's Long March family of launch vehicles can already accomplish most of what Beijing's leaders want to do in space, including building and supplying a planned space station early in the next decade. So there must be some other explanation for pouring billions of yuans into developing a super-heavy rocket. The official story is that China too wants to pursue deep space exploration, but here's another possibility.
Like SLS, China's planned super-heavy-lift rocket will have a much bigger diameter than anything in the current Long March fleet. That means the payload fairing at the top will also be wider -- wide enough to accommodate novel spacecraft that today could only be orbited with great difficulty. Spacecraft that might give the Peoples Liberation Army significant new capabilities.
For instance, America's National Reconnaissance Office reportedly operates a constellation of eavesdropping (signals intelligence, or "sigint") satellites with antennas the size of football fields. The satellites are used by the National Security Agency and other intelligence organizations to collect vast amounts of information about other countries generated in the radio-frequency portion of the electromagnetic spectrum.
But when the payload fairing on your rockets is only a few yards wide, unfolding such an antenna in space must be a pretty tricky maneuver. Ditto the solar collectors needed to power the constellation for years. How much easier would that task be if you had a really big rocket with a much larger diameter at the top? The same dynamic might apply to radar satellites that track the movement of warships at sea, or to the optical systems required by missile warning satellites that need to detect distant heat sources.
It isn't hard to imagine how China's military might be able to exploit a rocket that can lift 140-ton payloads in unusual shapes and sizes. The People's Liberation Army has a devilish time trying to figure out where U.S. aircraft carriers are at any given time in the Western Pacific. Its growing arsenal of long-range, highly accurate anti-ship missiles is useless if it can't find the targets. But with a super-heavy rocket, it might be able to deploy radar ocean reconnaissance satellites ("rorsats" in military vernacular) that could.
Because China trails the U.S. in satellite technology, a spacecraft matching the functionality of Lockheed Martin's Space Based Infrared System would probably be bigger and heavier in the Chinese configuration. With a super-heavy rocket, though, deploying such a constellation in geosynchronous orbit would presumably be much easier. Of course, the farther out you go, the less payload you can deliver. But the Long March 9 rocket Beijing has in mind could deliver 66 metric tons to geosynchronous transfer orbit.
That's a lot more than any U.S. military satellite currently weighs. So having a rocket comparable in size to NASA's Space Launch System could materially enhance the warfighting capabilities of China's military. Beijing presumably could use such a rocket in other ways to enhance its prestige, for example by lofting into orbit a space telescope far more capable than NASA’s currently planned James Webb system. There are lots of possibilities.
The bottom line here is that policymakers should be aware of the national-security potential that comes with developing super-heavy-lift rockets. SLS may be part of the civil space program, but that doesn't mean its technology is irrelevant to great-power competition in the military sphere. All the possibilities that a super-heavy-lift rocket opens up for China's military would become available to America's military as SLS evolves -- in much the same way NASA's Space Shuttle was originally expected to carry national-security spacecraft into orbit.
Transporting American astronauts to Mars, and maybe building a human habitat there, is a laudable goal. Few projects could demonstrate more convincingly that America remains a great nation. But policymakers shouldn't assume that is the only reason to keep the Space Launch System on track. The technology has other uses.
All of the companies mentioned in this commentary except Northrop Grumman contribute to my think tank. Lockheed Martin is a consulting client.
