I don’t know about you but I use the GPS Maps app on my phone quite often to find directions to a place where I have never been before. I use it even if I know three quarters of the way to get there so I will know exactly which street to turn onto and when. It makes me feel better when I hear that voice telling me to turn in 500 feet and then as I approach the street the voice says turn on such-and-such street. It also tells me how long it should take for each section of the journey. If the route was complicated toward the end I will tell the GPS to show me the route home. Sometimes the last few turns can get me confused when I start on my way back home. Did I turn left or right at this intersection? If I turned right to get there that means I should turn left on the way back. GPS has kept me from getting lost many times.
GPS utilizes the Atomic Clock for accuracy so do smartphones and so do satellites. What if we are planning a much longer journey, say to another planet? NASA’s Jet Propulsion Laboratory (JPL) website published a story dated June 4, 2019 and updated on June 14, 2019 written by Arielle Samuelson. The article’s title “Five Things to Know about NASA’S Deep Space Atomic Clock” gives us a good idea just how special this new atomic clock is and why it is so important. It’s hard to imagine that something the size of a toaster oven would be considered vital for long distance spaceflight.
These are the first two things you should know according to the article. The reason this new atomic clock is so important is due to the fact that they plan to use in to guide autonomous spacecraft from Earth to the moon and even to Mars. Before we tackle space we’ll take a look at how GPS actually works here on Earth. According to the article “Atomic clocks aboard satellites enable your phone’s GPS application to get you from point A to point B by calculating where you are on Earth, based on the time it takes the signal to travel from the satellite to your phone.”
The third thing is its accuracy. “It loses only 1 second in 10 million years. Any atomic clock has to be incredibly precise to be used for this kind of navigation: A clock that is off by even a single second could mean the difference between landing on Mars and missing it by miles. In ground tests, the Deep Space Atomic Clock proved to be up to 50 times more stable than the clocks on GPS satellites.” The scientists are hoping the test launch will prove that this is the most accurate clock in the universe.
Thing four is “It keeps accurate time using mercury Ions.” Quartz crystals are used in watches and regular atomic clocks. The electrical pulse that is sent through the crystal making it vibrate steadily just as the pendulum in a big clock, like a grandfather clock. The problem is that they can lose or gain time. I know my own wristwatch can be set exactly to the atomic clock time on my phone and within less than a month it can gain 10 seconds.
Quoting the article “The Deep Space Atomic Clock uses mercury ions – fewer than the amount typically found in two cans of tuna fish – that are contained in electromagnetic traps. Using an internal device to control the ions makes them less vulnerable to external forces.”
The fifth and final thing you need to know abut NASA’s new Atomic Clock is that “It will launch on a SpaceX Falcon Heavy rocket. The final quote explains “The Deep Space Atomic Clock will fly on the Orbital Test Bed Satellite, which launches on the SpaceX Heavy Falcon rocket with around two dozen satellites from government, military and research institutions. The launch is targeted for June 22, 2019 at 8:30 pm PDT (11:30 AM EDT) from NASA’s Kennedy Space Center in Florida and will be live-streamed here: https://www.nasa.gov/nasalive .
The way our spacecraft determine their position is by communicating with large towers back here on earth. The delay in sending and receiving that signal over the thousands and even millions of miles away would not be accurate enough. If the test of this toaster oven-sized atomic clock in space is as successful as expected it will revolutionize navigation in space.