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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.
Sugar Lump?
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 final development should see a battery-operated system about the size of a sugar lump."
"DO NOT EAT iAtomicClock"
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.
You'll have the most accurate caffine high ever.
...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...
Just turned fifty (give or take ten seconds.)
because without NTP, we might as well be using sundials.
...if nobody was actually measuring the time? I say zero and fifty years concurrently.
After 50 years the first atomic clock will have lost, what, a few thousands of a second?
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
50 years from now will we be talking about the birthday of the subatomic clock?
haa-ha!
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).
Laugh while you can monkey-boy. It'll all be the same in 2038.
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.
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!
GOD DAMN YOU SONS OF BITCHES! How hard is it to say, "one cubic centimeter"?
Anyway, isn't time to update the measurement of a "second" from the cesium atom? 1/9,192,631,770 is pretty vague in this day and age. Especially when france is "responsible" for all the "standards", and Paris is a city of change.
I say go for cobolt-60. Hell, it updates itself enough for Paris, with or without Joan.
Does it run Linux?
The Board of Directors of the Bulletin of the Atomic Scientists other nuclear clock
Uh huh, that's what it wants us to think....
"This food is problematic."
They might just "tick".. but you want them to tick at the right moment. otherwise you'd have two atomic clocks both accurate to themselves but off by as much as a second-- assuming you've got them synced to each other within a second or so..
With latency in relating the time from one atomic clock to another (I'd bet even the speed of light would factor in when syncing a new atomic clock to an old one), I wonder how they do it. They'd have to be very, very, confident in the accuracy of the lag. I also wonder how they set the first one in the 1940s.. ie, what did they use as a reference?
The atomic clock tells us what time it is, so no longer does time dictate what time it is, the atomic clock does. So, of course we never really now what time it really is. Especially because it's all relative to the Earth's orbit around the sun which, for all we know, could be decaying.
~Ilyanep
To get message, take amount of carrier pigeons at each stage mod 2. Then decode binary.
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/
The CIA? That blows any sort of credibility in the report. The CIA doesnt run "hakcers", the Department of Defense does, HQ'd on an Airforce base. It was publicised back in April in this article
The mantle IS NOWHERE NEAR the center of the earth. More /. titling sensationalism.
Still, drilling even 6 miles down is quite a feat
Does it run linux?
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...
This is serious. Somebody should stop them. Otherwise, they will pop the planet like a balloon, causing the insides to gush out into space, and the Earth's crust to fragment and fly off in all directions. Those parts of the crust left intact will shrink to a small fraction of their former size (just like a ballon's skin), once the air is let out of the Earth. On the plus side, traveling from point A to point B will take much less time, once the crust has shrunk, but point A and point B will themselves be much smaller. Houses in the suburbs will start to look like houses in the city, i.e., scrunched up against each other with small to non-existent back yards. No back yards! Where will yuppies hold their barbeques? My god, my god! We have to stop them before they pop the planet!
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
You point is completely true - but the money is not reobtained from consumers, but from savings made in the repair shop. Apple (like other electronics companies) state in their warrenties they can replace defective parts with refurbs, which are obviously cheaper than new items (example - my battery replacement they gave me for my iBook was a refurb). Thus, the cost of repair is reduced, and that's where the money is recouped.
There are about a billion ways you can replace the battery for about $50, so I'm not sure what the big deal is here. Even Apple will do it for $99.
Since a new iPod with similar functionality is $250-$299 (depending on how important extra storage space is to you), I'd say battery replacement is normally going to be worthwhile.
Unless you have an iPod broken for some other reason, I think the recycling is a bum deal.
D
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.
Wasn't this thrown off by the tsunami?
They have measured the (absolute) celcius temperature of a well-cooled system, without quoting the ambient temperature. Then, concluding that the temperature hasn't droppped much, they assume the power hasn't dropped much.
The correct measurement is the *difference* in temperature between the CPU and the ambient air. Power dissipation is linearly proportional to this.
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
Already welcomed our Atomicly Synchronized Overlords 50 years ago.
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.
Articles like this make me look forward to the 1960's..
They were really advanced.. and we're lame - we just have Internets.
Holy smokes, they can build spaceships, land men on the moon, but they can't take an inventory? What else do they have laying around?
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
My system is never idle. It runs seti@home and/or folding@home 24/7 in the background. So I don't think the power saving features will work for me if they depend on the processor being idle. I bought a Dell 500SC for home. It has been rock solid, but the fan is very noisy, and the DMA on the secondary IDE is busted (chipset bug). When I upgrade, I don't care about bleeding edge performance, I want it to be quiet. Wouldn't you know, after I bought the 500SC, Dell came out with the 400SC, which I've installed at several customers. That thing is quiet as a mouse. Sigh. I thought about switching and telling them, "See, 500 is better 400!"
No, most likely they did. From the article:
Other historical treasures found in the room include old film canisters, one flown shuttle main landing tire, electrical equipment, and various miscellaneous boxes.
Huh. Historical treasures, that just happened to be in a room which nobody said they had a key to. Huh.
Records show that official ownership of this suit was transferred by NASA to the Smithsonian Institution in 1983. The suit itself has now been returned to the Smithsonian.
Anyone else starting to realize that the stuff (which spans decades, completely different programs, and sections of NASA) didn't just get up and walk (either from the Smithsonian, or more likely, from other areas at NASA, never getting to the Museum) to a locked closet nobody said they had keys for?
Sounds to me like someone at NASA was building up their own private collection, and used a room they thought they had the only key to, not realizing there was a master key system in use./p
-
The point is...
Suspense = more clickthroughs = more ad views = more revenue.
The article is frustratingly vague. It sounds to me like the robot doesn't replicate itself but rather that Dr. Adrian Bowyer has created some type of system for replicating robot chasis. The picture clearly shows a plastic 'bot with attached motors, wiring, batteries, etc. From the information that the article gives, it seems like a human is still needed for the final construction. I wouldn't consider this self replicating because it is not autonomous.
This asshole (GP) posts similar crap near the top of every single article.
Please don't feed the trolls.
One part of the article that I think many slashdot readers will find interesting is near the bottom:
New here, aren't you?
I probably should have posted that as an AC.
So the question is: when is Palm going to fix/replace my Zire? It has two well-known problems:
<angry-rant>
Palm should have a better customer support but I suspect that the Harvard-CEO-type-of-mentality must dictate that its better to wait until users get organized and push a class action than just releasing a fix for software problems (point #2), because the latter would hurt the company's image (as if the class action wasn't bad enough).
<\angry-rant>/p
But God talks directly to Dubya.... and Osama and Kim Jong and.... Anrok Nobermiz an...
Have you noticed the difference in the BBC and NIST history pages?
According to NIST the idea of Atomic Clocks was proposed in 1945 by Isidor Rabi at Columbia University, and 'announced' in 1949 at NIST.
According to the BBC the idea of Atomic Clocks was proposed by Lord Kelvin in 1879, and built at the NPL in 1955 by Louis Essen.
I wonder whether there is any more importance to the 1949 and 1952 dates in the NIST history, beyond the fact that they are before 1955?
I'm in Canada, and would love to have my buggered m105 replaced.
Night vs. Day.
South Korea is the most "connected" nation in the world, with some 80% of households having broadband, and the average broadband connection being 4 MBits/s.
North Korea, well, can hardly feed themselves.
Take a look at North Korea vs South Korea in this NASA "Earth at night" image
Since aternatives keep up innovation, there is also a KDE 3.4 and such shiny new LiveCD http://www.t2-project.org/live/).
It even comes with D-BUS / HAL integration for auto mounting and equally perfect hardware detection.
As usual with the System Development Environment (SDE) T2, you can automatically rebuild it, optimized for your CPU - or even other architectures.
When the 1976 Viking experiments detected possible signs of life, one of the suspects was bacteria from Earth. Since it was believed that life wouldn't surive the trip to Mars, the validity of this hypothesis compared to the idea that the bacteria is Martian (or the idea that it was a false positive due to nonliving sources) has been the debate of scientists for a while. We'll have to wait until someone recovers the Viking probes to know the true source of that possible signature.
Totally off-topic, but I just got my first DVD burner, and I'm loving it. You should check out how cheap they've gotten -- I was surprised.
t egory=10
...
http://www.newegg.com/ProductSort/Category.asp?Ca
The burn-any-format drives are less than $50, and media is $35/100. That's definitely getting down in the why-the-hell-not range, for me
In North America at least, the trend has been going largely in the opposite direction. We are seeing REforestation rather than DEforestation. This is in despite of an increasing population.
m l
It can be a little tough to find good data given all the bullshit flying around but here's a map that shows the amount of forest land in the US from 1620 onwards:
http://www.eia.doe.gov/oiaf/1605/gg96rpt/chap7.ht
A move to more densley packed cities is also a contributing factor to reforestation.
Article such as the one Zonk cited are a favorite of the hard left environmental movement. These 'studies' cherry pick data to paint an alarmist picture. The media usually swallow these article whole with little crtical thought. In the end, these distorted pictures don't do anything to help real environmental progress.
Night vs. Day.
South Korea is the most "connected" nation in the world, with some 80% of households having broadband, and the average broadband connection being 4 MBits/s.
North Korea, well, can hardly feed themselves.
Take a look at North Korea vs South Korea in this NASA "Earth at night" image
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.
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.