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NIST-F2 Atomic Clock News Briefing: Opening Statement by Tom O'Brian

[full news release]

Good morning. And thanks, everyone, for joining us.

Today, we are delighted to officially announce the commissioning of NIST-F2, the most accurate official atomic clock in the world. NIST-F2 is now an official source of time for the United States—it has an accuracy that's equivalent to about one second in 300 million years.

My colleague, Dr. Steve Jefferts, led the decade-long effort of research, development and testing to make NIST-F2 operational. And Steve, in a moment, is going to tell us more about NIST-F2. But first, let me just give you a little bit of background about why we should care, and you should care about a clock that is accurate to one second in 300 million years, which is also 10 trillionths of a second per day.

Most people don't realize it, but we all rely on the exquisite precision of atomic clocks for much of the technology we use every day.

For example, the modern telecommunications and computer network systems that we're using right now for this webinar require synchronization to about 1 millionth of a second per day.

The electric power grid that is distributed across the continent that's powering our webinar equipment right now also requires synchronization to about 1 millionth of a second per day.

And the GPS system that's used to navigate airlines and our personal cars requires synchronization to about 1 billionth of a second per day. And now, most people are carrying around GPS with them all the time in smart phones and tablets.

All these technologies, and many more that we use every day, rely on exquisite timing and synchronization that is only possible with atomic clocks. And now, NIST-F2 is the ultimate reference in the United States for those long chains of atomic precision timekeeping.

The history of timekeeping is a story of increasingly rapid improvement in clocks, and those improvements directly lead to new technologies, often with very dramatic impacts.

The mechanical clocks in the Middle Ages were not very precise at all, but they were good enough for that society, which only needed to know when to gather for meetings or religious services. Mechanical clocks got better in the 19th century and the early 20th century, and started enabling new technologies like navigation of ships at sea.

But the real revolution in timekeeping came with the invention of the first atomic clocks around 1950, and that was done by NIST (we were then called National Bureau of Standards). And since then, there has been amazingly rapid improvement. Since the first atomic clocks around 1950, we've had a factor of improvement of more than a million, with improvements seeming to accelerate.

These amazing improvements directly led to advances in the many technologies we rely on every day such as telecommunications, GPS and the other things we were discussing.

On this graph that you're looking at, note that each tick on the vertical axis, the y axis, means improving by a factor of 10. So, two ticks means you've improved by a factor of 100, three ticks means 1,000, and so on.

If you look at the point for NIST-F1, which was the direct predecessor of the NIST-F2 atomic clock that we are announcing today—and Dr. Steve Jefferts also led that effort of NIST-F1— NIST-F1, when it first started about the year 2000, was about 10 times less accurate than NIST-F2 is today. So, over the past decade approximately, Steve Jefferts and his team have led to another factor of 10 or so improvement in atomic timekeeping.

So, NIST-F2 is a great advance on this continuing amazing march of science and technology. But as great as it is, scientists at NIST and across the world are already working on the next generation of atomic clocks that will be even better. In fact on the graph, you see that green dot saying "Optical Clocks, Research." Here at NIST and at other places around the world, we have atomic clocks that are already more precise than NIST-F2. Now these are research clocks, they're not anywhere near ready to serve as official timekeeping devices yet, but they will be in the future. So, even while we're celebrating this great achievement by Steve Jefferts and his colleagues in making the most accurate clock in the world, one of the burdens of being an atomic clock scientist is that you're aware that the competition is always sort of ahead of you all the time. That's exciting as well.

And based on lengthy experience, we expect that these improvements will not only lead to better use of things like GPS but will probably open up entirely new applications that I'm not smart enough to even think of.

Now, let me introduce my colleague, Dr. Steve Jefferts, who is one of the world's top atomic clock scientists and who leads the NIST-F2 team.

Created April 3, 2014, Updated December 30, 2016