Blog Editor’s Note: Interesting assertion by two authors who should know what they are talking about.
Conventional wisdom has been that GPS is a constellation and anti-satellite satellites (ASATs) can only attack one other satellite. So very hard to impact GPS performance and service.
These gents point out that in a few years China (maybe Russia too?) will have enough ASATs in space that it can destroy or jam the whole constellation at once.
Of course we could do the same to Bei Dou. But then they have PNT satellites at GEO and LEO, eLoran, and seem to be developing other PNT systems as well in conjunction with 5G deployment.
Last fall Senator Sasse, a member of the Senate Select Committee on Intelligence, remarked that in a cyberwar, China would take out GPS and military communications satellites first. The senator is another person who should know what he is talking about.
And if you were China and wanted to attack the U.S. without initiating a nuclear exchange, that might seem to be a good way to do it.
Even GPS is likely to be vulnerable by the late 2020s. Thus far, GPS has been broadly resilient to ASAT attack due to various countermeasures and its redundant design. The GPS constellation consists of about three dozen satellites, each orbiting twice daily, only four of which need to be over a given area at once to sustain service. For this reason, degradation is gradual, not catastrophic: even destroying six satellites at once would only deny service to a localized area for about 95 minutes per day. If, however, one could disable most of the constellation, the result would be near-total loss of GPS services worldwide. While this is largely infeasible with current ASATs, by the late 2020s China may have enough RPO-capable small spacecraft to preposition near every GPS satellite, allowing at-will disablement of the entire constellation. These threats underscore the need to carefully examine each next-generation ASAT individually, in order to identify in advance any unique characteristics which might upend prior assumptions. Doing so is the only way to avoid strategic surprise, and would reveal which threats do (and don’t) deserve priority and how solutions should be designed.