You can’t hack the stars You’re probably familiar with GPS as the handy tool to fin

You can’t hack the stars You’re probably familiar with GPS as the handy tool to find your way to a new restaurant, or to make sure you don’t end up in the middle of nowhere on a road trip. But its uses are widespread, from farming and mining to banking to weather forecasting, as well as being crucial to security and military operations. Our GPS system is a space-based navigation system made up of 24 satellites in geostationary orbits, sending signals down to GPS enabled devices to help determine precise locations and times. But both natural phenomena and deliberate attacks pose real threats to these satellites and the way we use them: massive solar flares could disrupt their signals, jamming devices could block GPS devices on the ground, and electromagnetic pulses could shut off the power of a military vessel or aircraft. If you’re in the middle of the ocean or high over enemy territory, losing your navigation system would be a huge problem. That’s why the US Navy have gone back to basics and decided to train their new personnel in a traditional navigation technique known as celestial navigation. Celestial navigation is an ancient skill, used for most of human history by sailors and explorers who guided their ships based on the stars. It’s a bit more time consuming and unwieldy than GPS, but it works - it basically involves finding the positions of the stars in the sky and then comparing them to an almanac of compiled measurements for various locations. A few calculations later, and voila, the position of your ship can be triangulated to within a few kilometres - no computers of satellites required. This is much less accurate to the few metres precision that GPS gives us, but in a back up, it’s pretty damn handy. After cutting it out of the curriculum more than a decade ago, the US Naval Academy have now fully reintroduced celestial navigation as a course - and the graduation class of 2017 will be the first in over a decade to graduate with such traditional navigation skills. After all, malicious forces could potentially bring down GPS systems, but they can’t change the position of the stars in the sky. -- source link

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