US Navy renews training in celestial navigation over GPS hack fears


We often talk about the importance of file backups, for some pretty good reasons: hard drives can be damaged or lost, files can be corrupted or scrambled beyond repair by ransomware, and even Google’s data stores aren’t invulnerable to natural disasters.

It’s not just your files that need to be backed up – generally, it’s a bad idea to rely on any system with a single point of failure.

Apparently, the US Navy has come to the same realization regarding navigation of ships, which depends on the availability of the Global Positioning System (GPS), operated by the US Air Force.

This year, the US Naval Academy has decided to reinstate instruction in celestial navigation, teaching a course on navigating by the stars for the first time in 10 years, according to a newspaper report from Annapolis, Maryland, home of the academy.

Midshipmen set to graduate in the class of 2016 received just three hours of instruction in this venerable navigation technique – not enough time to become expert in using a sextant – but the Naval Academy class of 2017 will be required to learn theories of celestial navigation in an advanced navigation course.

Lt. Cmdr. Ryan Rogers of the Naval Academy’s Department of Seamanship and Navigation explained the decision to resume teaching celestial navigation this way:

We went away from celestial navigation because computers are great. The problem is, there's no backup.

Rogers went on to say that it’s possible the US’s GPS system, which relies on 31 satellites to give location coordinates accurate up to within a few feet, could be shut down in a national emergency to prevent enemies from using it.

There’s also the possibility of enemies taking out the GPS satellites, a scenario the Pentagon has been war gaming, and the threat of “cyber vulnerabilities,” Rogers said.

Even without attacking the GPS system directly, an enemy could potentially turn GPS navigation against the Navy, by spoofing GPS signals.

In 2013, a team of researchers from the University of Texas demonstrated how attackers could send counterfeit GPS signals and take over a ship’s navigation system.

When we reported the story on Naked Security, a few smart commenters recognized the need for a backup navigation system:


cindelicato: Time to break out the sextants!

abeastwood: A good idea, if anyone on the crew knew how to use one or even what a sextant was. Oh, and compass and good chronometer would help, too.

Now that the US Navy is bringing back celestial navigation, we might want to ask ourselves what other technologies we depend on without a backup, and what would happen to us if those technologies failed.

When the lights go out, we have flashlights or candles; when we lose power from the electrical grid, we can use a gas-powered generator.

It makes me wonder though – what would we do if a catastrophic failure took out the internet?

Image of sextant on old map courtesy of