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Atomic Clock Turns 50
karvind writes "BBC has an interesting story on the 50th birthday of atomic clocks. The first accurate caesium atomic clock was developed at the NPL in 1955 by Dr Louis Essen. And after 5 decades In September the US National Institute of Standards and Technology (NIST) used computer chip fabrication techniques to make a small atomic clock. The final development should see a battery-operated system about the size of a sugar lump. NIST also has a page on history of atomic clocks"
It's a good thing we had atomic clocks so we could be sure it was really 50 years!
A beryllium atomic clock...just what the Doctor ordered!
Jelly baby?
^_^
____
~ |rip/\/\aster /\/\onkey
Lump of sugar has to be the oddest comparison ever...
There are exactly 42,935,718 letter sized sheets in a square mile.
I used to be obsessed with accurate clocks, still am for my servers, but after awhile its all relative anyway ;)
The more you know, the less you understand.
The atomic clock turned 49.9999999999999999999999 today!
;)
Congratulations
liqbase
It seems that more and more of everything is sync'd with this. My clock radio at home auto-updates, clock on the wall, the cellphones, my Linux and Mac PC's and cable box.
Only thing left are the clocks with a single AA battery on the wall, and at some point they are going to use the pervasive WWVB time signal that is broadcast from Colorado and operated by the National Institute of Standards and Technology
This technology has really come a long way and is deeply embedded within our lives. Especially if you consider that before the atomic clock, time varied considerably between different locales.
Newsfollow.com
and we still don't have time travel. What a shame.
That article is not precise! The atomic clock is 50.00000100121412235901293409234 years old as I'm writing this.
...atomic clocks are old enough to get classified as antiques & collectibles. Kids with ultra-wristwatches that tell your exact location by relativity effect at walking speed will laugh and laugh. You will be able to by them as cheap gifts for little kids at the $2,000,000,000,000 shop without a second thought.
thank you for ore abilty to micro manage our lves
I am a viral sig. Please copy me and help me spread. Thank you.
How the hell do the British see see-zee-umm in that? Tsai-sai-umm?
Four scientists, as they flip the switch on their new invention ...
... ...
#1: Gee, Ed, it looks like it works
#2: Bob, you're right! It's counting! We did it!
#1: It seems to be right on, let's fire up the chronotaph
#3: Already there, Bob, I have a solid register, five-nines. I started the paper before you hit the button.
#1: Good thinking, Stan. This is one for the record books!
#2: This is a clock for your ass, Ed! I guess we should set it now.
#4: Okay guys (looks at watch) what have you got? I'm showing a quarter past two.
"As net data is split in data streams and reassembled, for instance, the timing has to correct at the point of re-assembly.
If not, whatever data has been sent - voice packets in VoIP net phone calls for example - will come out garbled."
Did anyone else laugh as they read this? The writer of this article is unaware of sequence numbers... (and thinks that a timestamp is placed on each packet instead.) Wow. But this could also work with the computer's internal clock... though then all routing devices would have to be initialised to the same time. But I digress...
because without NTP, we might as well be using sundials.
...if nobody was actually measuring the time? I say zero and fifty years concurrently.
This is a question that must get asked a lot, and I wasn't able to find an answer (casually searching) on the gov website.
How did they figure out how to set the clock initially? Thanks.
Seriously... how do you set the time on one of them?
dominionrd.blogspot.com - Restaurants on
sometimes you will read about how the most accurate clock in the world is accurate to within 1 second every 30 million years or so. if it is already the most accurate clock, how would they know this?
Anyone see that article a couple of weeks ago in New Scientist about Strontium atoms held in standing waves generated by 6 lasers? Mental. A 50 time more accurate (or something).
After 50 years the first atomic clock will have lost, what, a few thousands of a second?
it could just as easily have gained a few thousanths of a second. It was only the first one, so it could have been pretty inaccurate.
Tag lost or not installed.
...the worlds first atomic wristwatch.
Ash:"Gimme some sugar baby."
now we know why he was lost in time...
-- it's ridiculous how many people misspell ridiculous... (damn, damn, damn...)
So, most of the non-live TV shows are on time. It is probably impossible. :(
Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
Fine but what nanosecond does its birthday roll over?
49.999999999999999999923409
Table-ized A.I.
I guess I'm just not getting all this timekeeping stuff. I've been aroud for over 1,308,744,000+ seconds and I still don't _feel_ any older...
INSERT INTO comment VALUE('Doh!') WHERE user='you';
and all the staff had a surpise birthday party for the bi-centinary birthday.
Although the surpise was too much for dear old atomic, and his ticker stopped ticking. He was rushed to hospital where he had a pacemaker installed. He has lost several hours which officials have decided to relocate him to a warmer climate on a different timezone to make up for the difference.
The operation and pacemaker will not shorten the expected lifespan of atomic.
Automation - The Car Company Tycoon Game
Now, tell me exactly when it first became operational, down to the precise NANOSECOND!
Uh huh, that's what it wants us to think....
"This food is problematic."
There is a project to serve NTP round-robin from a number of servers. You can use this pool thusly with ntpd:
server pool.ntp.org
If you live in Canada or the US you can even do:
server north-america.pool.ntp.org
Read more at:
http://www.pool.ntp.org/
Not only is the speed of light a problem, but relitivity as well. If you put the atomic clock on a train and send it thirty miles down the track it would lose time.
Setting the first one was easy. They just checked their wristwatches. Its not as important that the clock have the correct time, as it is that it keeps the correct time.
something that doesn't exist.
If you could reason with religious people, there would be no religious people
I thought Intel wasn't around fifty years ago...
I mean, it could be lying about its age. If you disagree, what clock can you consult for arbitration?
Computers are useless. They can only give you answers.
-- Pablo Picasso
China is going to become dominant in Asia no matter what, I'm afraid. That's been inevitable for a century. There's damn little the US can do to stop it.
The world's burning. Moped Jesus spotted on I50. Details at 11.
In the old days, it was common to use "flying clocks" to synchronize atomic clocks around the world. A flying clock is just a portable version of an atomic clock, with a rechargeable battery for its power supply. Someone would take the flying clock to the place where the primary time standard was maintained, synchronize it with the primary time standard, and hop on a commercial airplane flight to the field site. When they arrived at the field site, they would synchronize the local atomic clock with the flying clock. I've seen a flying clock that was built into a medium sized suitcase. The clock usually had its own seat and airplane ticket while traveling. Today, for most applications it is simpler to install a GPS receiver that is designed for time/frequency distribution.
Mea navis aericumbens anguillis abundat
According to the article, it doesn't appear there were any previous celebrations ... and in the BBC piece it doesn't say if the clock got to do anything for turning 50. I climbed a mountain on my 40th birthday - someone ought to throw a party for the poor old clock! ;-)
Hulk SMASH Celiac Disease
Invasion, partition, and occupation would probably do it. No, not a good idea, just saying it's not really inevitable.
You've got to be plain stupid to think the United States could ever take China out by itself, or even with the help of nothing short of the rest of the world.
China's population is several times the population of the United States, and if I recall correctly, its standing army is larger than the population of the United States. It doesn't matter if the US 'has the best weapons in the world for the best soldiers in the world,' as one man with an M16 can easily be disabled when there are 100 expendable persons with clubs and sword and whatnot aiming to kill him.
The only way the United States could destroy China (as there is no hope for occupation) would be to nuke it, and China would nuke us right back, and no one would win.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
50.00000000000000000000014 years (with uncertanity +/-2 in the last decimal place)
I doubt that we will ever figure out - and I suspect that even if we did figure out we couldn't do much about it
The parent post is off-topic, and is a verbatum copy of this post, which is on-topic in this thread.
It was obviously posted by some sort of troll-bot.
Please moderate the parent post down as off-topic, and the original post up as funny.
No, I am not the original poster.
Really, I'm not.
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
But God talks directly to Dubya.... and Osama and Kim Jong and.... Anrok Nobermiz an...
Parent post (Re:Caesium) is about "Atomic Clock Turns 50"
:>
Three replies as I type this:
1. : "since knoppix uses a very cleverly hacked filesystem layout" ???
2. : " was curious to find that 5th picture, talking about using insects to control a green swirl". I think that belongs with Changing Planet Revealed In Atlas
3. "I'm sorry, but what qualification does CNET have to bestow open source software awards". CNET to Award Open Source Initiatives, anyone ?
Looks like Slashdot's a bit borked
The ironic thing about an atomic clock is that you have to have a computer to read the time. I saw one once at Kitt Peak National Observatory, and it was just like a server in a room without a terminal. No display, not even a digital display, to tell the time. They didn't even have an analog clock on the wall.
From the article: "The first atomic clock ... was born at the UK's National Physical Laboratory."
Well, the first -cesium- atomic clock was made at NPL, UK, which was certainly a major advance. But the FIRST ATOMIC CLOCK was built at the National Bureau of Standards (NBS) which is now known as NIST, in the US. So I disagree with the BBC's presentation of the situation.
Check out http://physics.nist.gov/GenInt/Time/ for more info and history than what was linked in the original post on this topic.
Been tried before. It failed, Now China has nuclear capabilities, and while she might not be able to take out anything in the US, well I'm sure Japan would appreciate a few more mushroom clouds.
The world's burning. Moped Jesus spotted on I50. Details at 11.
You're kind of ignorant here. Technology is a lot more important than sheer numbers, and who the hell cares if someone has a club if you're in a bomber 50,000 feet above them? Just look at the past, China has always had a population advantage and that didn't keep Japan from just rolling over Manchuria, or the various Western powers from grabbing whatever cities they felt like.
Your mom runs linux.
The more you know, the less you understand.
The Big International Scientific Conference that got together to define a new time scale to replace GMT had no difficulty coming up with the name "Coordinated Universal Time", but deadlocked when it came time to decide between the English acronym (CUT) or the French one (TUC). So they decided to use the symbol UTC, which doesn't stand for anything.
Leap seconds are used to keep UTC in sync with the Earth's rotation. Since the Earth's rotation is steadily slowing down, UTC would drift away from any sensible time if it wasn't adjusted every now and then. So they add the occasional extra second to keep them in sync.
GPS time runs at the same rate as UTC, but has no leap seconds, and is currently 13 seconds different. People who navigate by the stars use UT1. Then there is the Terrestrial Dynamical Time that astronomers use, which is another matter entirely.
...laura
My dad, David W. Allan, worked with the Atomic clock at NIST until 1992 when he retired. The "Allan Variance" is an algorithm at the heart of international time-keeping.
He has continued his research on a tangent subject of a new unified field theory. He is in process of implementing some of his theories by way of ultra-precision positioning. You might find his theory worth review. AllansTIME.com
He also has passion in the subject of health. His solar home is likewise a hallmark of his forward thinking. http://allanstime.com/SolarHome/
Tomorrow's news yesterday -- the bleeding, visionary edge.