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NASA To Test New Atomic Clock

samzenpus posted more than 2 years ago | from the no-time-like-the-precise-present dept.

NASA 79

edesio writes "Many satellites and spacecraft require accurate timing signals to ensure the proper operation of scientific instruments. In the case of GPS satellites, accurate timing is essential, otherwise anything relying on GPS signals to navigate could be misdirected. The third technology demonstration planned by NASA's Jet Propulsion Laboratory is the Deep Space Atomic Clock. The DSAC team plans to develop a small, low-mass atomic clock based on mercury-ion trap technology and demonstrate it in space."

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Maybe (1)

Anonymous Coward | more than 2 years ago | (#37768124)

Maybe this one will be able to do something as simple as timing neutrinos properly.

Take the L out... (0)

tootalltom (1097273) | more than 2 years ago | (#37768160)

...and I think NASA might actually get some of their funding back...

Re:Take the L out... (2)

sexconker (1179573) | more than 2 years ago | (#37768474)

All they need to do is send 1 male and 1female astronaut up, pretend to tell them to have sex, and then pretend to find out they exhibit all the typical dysfunctions your 40+ laze abouts do.
Then send them up again, tell them them to take these special space sex placebos, and put out a press release along the lines of "First Child Conceived In Space Thanks To New Sex Pills!".

Re:Take the L out... (1)

Doc Ruby (173196) | more than 2 years ago | (#37770808)

You forgot to Post Anonymously.

Re:Take the L out... (0)

Anonymous Coward | more than 2 years ago | (#37780320)

Why bother, with a name like Sexconker?

Could become the final nail in Einstein's relativi (-1)

lamare (1349411) | more than 2 years ago | (#37768182)

Very interesting. If the mass is low enough, we may see yet another "anomaly" shaking the main stream science community, who still believes in Einstein's relativity theory, which is so obviously wrong that it is almost beyond believe it has survived for more than 100 years.

I have sent this article to some professors and a guy who claims to have found the error in the Neurtrino anomality at CERN and so far no reply:
http://www.tuks.nl/wiki/index.php/Main/Ruins96YearsEinsteinRelativity [www.tuks.nl]

"Last week the newspapers were filled with the discovery of "impossible" particles traveling faster than the speed of light. A month ago an "impossible" star was discovered and earlier the Pioneer space probes also refused to adhere to the law. This way, the scientific establishment will slowly but surely be forced to return to reality, the reality of the existence of a real, physical ether with fluid-like properties. The inevitable result of that will be that Einstein's relativity theory will go down in the history books as one of the biggest fallacies ever brought forth by science. In the future they will look back to relativity with equal disbelief as to the "Earth is flat" concept. The relativity theory not only goes against common sense, as Tesla already said in 1932, a fundamental thinking error has been made by Maxwell in his equations. This eventually lead to the erroneous relativity theory, as is proven in this article. It is therefore no exaggeration to state that the scientific establishment is going to have a religious experience. "

Keeping my fingers crossed....

Re:Could become the final nail in Einstein's relat (1)

xMrFishx (1956084) | more than 2 years ago | (#37768324)

If you have an idea, try and prove it wrong (alot), if you can't, then your idea stands. This goes for relativity too, but dancing around just saying "it's wrong, haha!" gets you a Cool story bro award attached to a tin foil hat.

Re:Could become the final nail in Einstein's relat (0)

lamare (1349411) | more than 2 years ago | (#37768396)

I did point to my article, where you can find the proof. It's just plain logic and common sense.

We'll see how it turns out. I just know I did my homework.

Re:Could become the final nail in Einstein's relat (2)

MyLongNickName (822545) | more than 2 years ago | (#37768430)

Oh, that is YOUR article? BWAHAHAHAAA. Sorry, I will stop arguing with you now. Only an idiot continues to argue with fools.

Re:Could become the final nail in Einstein's relat (1)

amirulbahr (1216502) | more than 2 years ago | (#37770590)

He can't be that stupid. Maybe we've been trolled.

Re:Could become the final nail in Einstein's relat (3, Informative)

Graymalkin (13732) | more than 2 years ago | (#37768340)

Very interesting. If the mass is low enough, we may see yet another "anomaly" shaking the main stream science community, who still believes in Einstein's relativity theory, which is so obviously wrong that it is almost beyond believe it has survived for more than 100 years.

You certainly typed a lot of words to say "I don't know what the fuck I'm talking about". As far as scientific theories go relativity has a lot of very strong experimental [wikipedia.org] support [wikipedia.org] . Though I suppose if you want to say it's "obviously wrong" you might want to include some actual experimental verification or even peer reviewed papers of such a claim, you know, to enlighten us bozos.

Re:Could become the final nail in Einstein's relat (1, Interesting)

Synerg1y (2169962) | more than 2 years ago | (#37768670)

Based on the relativity theory though, humans are pretty much earthbound, Mars at best. 1 light year = guess what?

To achieve anything significant in the universe, it's pretty obvious it needs to be broken.

All of our theories, laws and measurements are earth based and earth bound.

Now Einstein's theory is probably 100% on planet earth in our current physics model, but I'ma laugh if you say it applies to a place in space thousands of light years away. It very well may, but neither you nor I can prove that, and pixelated images from a space telescope aren't going to reverse that chain of thinking.

Also Einstein wasn't aware of the physics picture we have going on right now with quantum mechanics and subatomic particles.

I think the goal is to ultimately evolve our physics model to compensate for new discoveries and hopefully utilize them.

Also, in regards to not knowing what your talking about...
http://www.newscientist.com/article/mg18524911.600-13-things-that-do-not-make-sense.html [newscientist.com]

there's some food for thought in regards to shit nobody knows what they're talking about... including... YOU!

Lastly, there's a more than a few links on this from various places...

http://ibnlive.in.com/news/would-einsteins-theory-of-relativity-be-proved-false/187145-11.html [in.com]

It's all speculation at this point, I'm certainly not saying it's going to be broken by a long shot, but as I stated at the top, it needs to be to coincide with all those sci-fi movies and keeping an open mind never hurt anyone.

I'd take a one size fits all cure for cancer before this shit though.

Re:Could become the final nail in Einstein's relat (1)

bky1701 (979071) | more than 2 years ago | (#37770202)

It is possible to not break relativity, but go faster than the speed of light. It all comes down to how speed is defined - and it turns out that relativity has a fairly narrow definition.

Re:Could become the final nail in Einstein's relat (1)

Doc Ruby (173196) | more than 2 years ago | (#37770820)

Just because you don't know what the hell you're talking about doesn't mean no one else knows what they're talking about.

You're stupid.

Re:Could become the final nail in Einstein's relat (1)

Synerg1y (2169962) | more than 2 years ago | (#37774372)

Your a fuckin retard for even replying to any post. There's a hole somewhere for you, it's not on the internet though.

Re:Could become the final nail in Einstein's relat (1)

Graymalkin (13732) | more than 2 years ago | (#37771114)

Also a lot of words to say "I don't know what the fuck I'm talking about".

Re:Could become the final nail in Einstein's relat (0)

Anonymous Coward | more than 2 years ago | (#37768342)

Well, you're definitely not crazy!

Re:Could become the final nail in Einstein's relat (0)

Anonymous Coward | more than 2 years ago | (#37768344)

That's a special kind of crazy you've got going there.

Re:Could become the final nail in Einstein's relat (2)

MyLongNickName (822545) | more than 2 years ago | (#37768370)

Besides your link to some dude's blog, what is your support for saying Einstein's theories are "obviously wrong"?

If his theories are wrong, how do you deal with the fact that they have been supported with countless experiments, and our GPS system depends on his theories to keep accurate timings down to the billionth of a second?

Re:Could become the final nail in Einstein's relat (1, Interesting)

lamare (1349411) | more than 2 years ago | (#37768456)

It's my own site, I pointed to....

Einstein's theory stands or falls with the speed of light being constant. Since that depends on the properties of the medium, apparantly these are pretty constant in the vicinity of the planet, which is why the theory gives you the correct numbers in 99 out of 100 cases. You'd expect anomalies further out in space, and that is exactly what you see. Take the Pioneer anomaly, for example. That also only gives slight deviations of what is supposed to happen now the probes are very far out in space.

However, the root of the error is very obvious. Either matter is some kind of EM wave, as QM theory and the wave-particle duality principle says, and is therefore the result of the EM fields, or matter (charge carriers) is the cause for the EM fields to exist. And you simple can't have it both ways at the same time. It's one or the other.

Re:Could become the final nail in Einstein's relat (1)

MyLongNickName (822545) | more than 2 years ago | (#37768480)

The Pioneer anomaly has been explained by far less exotic answers... thermal radiation pressure is the likely culprit. Sorry, but you sound like a conspiracy theorist more than a scientist.

Re:Could become the final nail in Einstein's relat (1)

grumbel (592662) | more than 2 years ago | (#37769506)

Einstein's theory stands or falls with the speed of light being constant.

Yeah, and so far our experiments have confirmed that over and over again. That doesn't mean that the theory is right, in fact we know that it is very likely wrong, as it doesn't play nice with quantum mechanics, but science isn't about right or wrong or finding absolute truth, it's about finding the best theory to explain and predict our observations and so far the theory is the best we got. If our experiments get more detailed and unexplainable reproducible errors show up, then we might need to update the theory, but that hasn't happened yet.

Take the Pioneer anomaly, for example.

This one [wikipedia.org] ?

Most recent developments point towards the mundane cause of thermal radiation pressure forces inherent in the spacecraft.

What you are doing is Anomaly Hunting [theness.com] , one tiny unreproducible glitch in the data doesn't mean that we have to through all our working theories out of the window, it means that we have to either explain the glitch or look for a way to reproduce it.

Re:Could become the final nail in Einstein's relat (0)

Anonymous Coward | more than 2 years ago | (#37771568)

What I did is study quite a lot of material on Electrical Engineering, which is also the discipline I hold a Masters degree in. Then I connected the work of Dr. Charles Kenneth Thornhill and Prof. Konstantin Meyl and thus discovered ecactly where a fundamental thinking error was made in the Maxwell equations. Matter is some kind of EM wave phenomenon and therefore it is caused by the fields. So, when you postulate that the fields are caused by charge carriers, matter, you mix up cause and effect, which ultimately leads to the conclusion that the relativity theory can't be correct, as you can read in my article.

Re:Could become the final nail in Einstein's relat (1)

Doc Ruby (173196) | more than 2 years ago | (#37770830)

The constant speed of light is constant only in a given medium. Not only Einstein, but plenty of other scientists and mathematicians have covered that completely. Einstein's models account for different media.

You're just another childish egotist who thinks Einstein's work was some kind of great big "gotcha", so you'll just pull one off yourself.

You're stupid. Shut up.

Re:Could become the final nail in Einstein's relat (3, Informative)

MyLongNickName (822545) | more than 2 years ago | (#37768420)

And you link to a blog which states
"This way, the scientific establishment will slowly but surely be forced to return to reality, the reality of the existence of a real, physical ether with fluid-like properties."

You realize that the "ether" theory has been absolutely blown out of the water, right? Countless experiments were conducted to determine our motion through this either. all experiments showed the speed of light does not depend on the observer's velocity. It was only after these countless experiments that science finally accepted that there is no absolute vantage point.

But if you don't even understand this, you should presume to disagree with Einstein. Free speech may entitle you to disagree... but free speech also entitles the rest of us to call you out for the uninformed person that you are.

Re:Could become the final nail in Einstein's relat (0)

Anonymous Coward | more than 2 years ago | (#37768448)

One thing that the Internet never fails to deliver is crazy people with theories about physics. Who's the bigger fool, the fool, or the fool who follows him? You need to stop reading wacky physics advice from Internet crazies and find something better to do with your time. The reason you've gotten no replies after forwarding your silly link to physics professors is that physics professors are inundated with stupid articles claiming that relativity is wrong, or the number of spatial/temporal dimensions is wrong, or thermodynamics is wrong, or whatever. Most of them have given up on trying to refute people with wrong ideas because crazy people can't be reasoned with, and it's a complete waste of time. But look at me, trying to reason with an Internet Physics Crazy; apparently, I haven't learned my own lesson.

Re:Could become the final nail in Einstein's relat (1)

Sarten-X (1102295) | more than 2 years ago | (#37768464)

The "impossible" particles are likely due to miscalculation of relativity effects due to GPS satellites moving. The "impossible" star is possible under the laws of physics, but so improbable that it goes against theories of the exact sequence of events leading to a star's formation, and has nothing to do with relativity. The Pioneer anomaly has many possible causes, few of which involve a new cosmological theory.

Sorry, but worship of Tesla is just as bad as worship of Einstein.

Re:Could become the final nail in Einstein's relat (2)

Baloroth (2370816) | more than 2 years ago | (#37768528)

Tesla was a genius, and in the quote you gave I believe he was right... but also wrong. Space cannot curve if space is nothing. But space is not nothing. The work of people like Riemann and Lobachevski have shown that space can in fact possess properties inherently. This makes a kind of sense: when we talk about 5 feet of space, that space has an objective reality and possesses some property (namely, dimension) that allows use to quantify it. Einstein deals with this question somewhat BTW.

Interestingly enough, if you go back to the philosophy of people like Aristotle, "matter" can possess any level of properties, including (in theory) insensate but quantitative dimensionality (i.e. "empty" space). So space could be "material" in this original sense, allowing for curvature, yet be "empty", in the sense that it lacks tangibility (which is really what we mean by "empty" anyways).

Re:Could become the final nail in Einstein's relat (2)

Chris Burke (6130) | more than 2 years ago | (#37768790)

Last week the newspapers were filled with the discovery of "impossible" particles traveling faster than the speed of light.

And while Relativity must be subjected to the highest standards of evidence(and is), this discovery of course must be accepted as the complete truth as soon as it comes out.

earlier the Pioneer space probes also refused to adhere to the law

I love how the Pioneer Anomaly is always used as proof of whatever crackpot theory someone wants it to, or dis-proof of whatever theory they want to discredit even if only tangentially related. But in reality, anomalies like this are usually best understood by more fully understanding the circumstances. For example, once someone went to the trouble to more accurately model the way light would reflect off of the Pioneer probe's structure, suddenly the Pioneer "anomaly" went away.

Oh, I'm sorry, was I only allowed to assume that all of science was wrong when figuring out what was going on with a weird observation? Theories are fair game, but the methodologies and calculations used to determine if the theory's predictions are correct can't be updated? It was called an "anomaly" before, ergo Relativity must be wrong?

And... you think this is a more intelligent way of approaching science?

In the future they will look back to relativity with equal disbelief as to the "Earth is flat" concept.

You mean they'll view it as a theory that fit all available evidence better than any other available theory, up until the time that it didn't and then it was abandoned? You're probably right. BTW, that happened a lot earlier than most of you folks who trot out the Flat Earth Theory think. The earth was understood to be round, and even it's circumference calculated with a surprising degree of accuracy, in around 200 B.C. But comparing Relativity to the Spherical Earth Theory (which is wrong) would be too honest.

Relativity, like the flat or spherical earth theories, will last as long as it's the best theory -- and unlike the Flat Earth, but more like Classical mechanics, it is likely going to be close enough to correct that it will still be used for a wide variety of circumstances even in this hypothetical future you envision.

The relativity theory not only goes against common sense

Quantum Electrodynamics pisses all over your precious "common sense" while cackling like Pennywise the Clown, yet it has been verified experimentally to 15 decimal places.

Even basic probability goes against common sense, but guess which one does a better job of predicting what you should bet on a hand in poker.

But hey, I have to admit, Tesla said Relativity had to be wrong, so I guess it must be.

But wait, those mainstream scientists who "worship" Albert Einstein still adhere to QED and QM even though Einstein said they didn't make sense and he didn't like them.

Gee, I wonder which group of people it is -- mainstream science or "rebel" science --that actually evaluates theories on their merits, and which just picks authority figures who say what they want to hear?

physical ether with fluid-like properties... a fundamental thinking error has been made by Maxwell in his equations.

Kinda funny how they propose an aether theory, while also saying Maxwell is wrong (despite truly ridiculous amounts of verification), when the whole reason the aether theory was proposed in the first place was to explain how the speed of light in a vacuum could be constant, as implied by Maxwell's equations, in the presence of relative motion.

Keeping my fingers crossed....

And that's... pretty much all you're doing, isn't it? Scientists have been subjecting their theories to every test they can come up with, developing alternative ones and comparing the predictions they make to the evidence, and seeing which comes out best and picking that one. Crackpots pick one or two things that are difficult to explain, claim that proves them completely right and everything else wrong, and ignore the mountains of evidence their crackpot theory can't explain.

Re:Could become the final nail in Einstein's relat (1)

GameboyRMH (1153867) | more than 2 years ago | (#37768994)

Wow my list of science deniers has AGW denialists, anti-vax'ers, stem cell denialists and now a theory of relativity denialist!

Best line in your article:

And because space is not physical at all, it can have no physical properties.

XD

Re:Could become the final nail in Einstein's relat (1)

Chris Burke (6130) | more than 2 years ago | (#37769230)

Heh. That's nothing new, really. Ever heard of The Electric Universe? Whole gaggle of crackpots who claim the universe is dominated by electricity while simultaneously not understanding it. Not only is Relativity out for them, but even Newtonian gravity doesn't explain the motion of planets as far as they're concerned.

I gotta admit, though, this is a new take on crackpottery and that's always amusing.

Not quite as amusing as the Conservation of Momentum/Energy Denialist that was haunting Slashdot for a while. That was pretty impressive.

Re:Could become the final nail in Einstein's relat (1)

GameboyRMH (1153867) | more than 2 years ago | (#37773918)

A Conservation of Energy denier? Wow how does that work? Sounds like it could be a troll presenting Troll Science with a serious face.

I've seen plenty of crackpot forums but you don't expect their users to post on Slashdot. The Flat Earth Society is hilarious, but a lot of people say it's a big joke, like if Conservapedia was run entirely by Conservatroll players.

If they were serious they would be the most vocal environmentalist protesters, because if that ice wall melts most of the water would fall off the world.

Re:Could become the final nail in Einstein's relat (1)

Chris Burke (6130) | more than 2 years ago | (#37774804)

Well, they weren't explicitly a CoE denier. They were explicitly a CoM denier who was just ignorant of the connection... They proposed an Aristotlean theory of motion, where an object maintaining non-zero momentum required a constant input of energy, and you could use this universal energy to ignore momentum and instantly start and stop or turn 90 degrees like the old Light Cycles from Tron.

They easily could have been a troll, but they went to a lot of trouble for it. They had their own blog with a lengthy screed about how Newton and every other scientist since was wrong and Aristotle was right and how obvious it all was. Even had out-of-context quotes from The Principia that tried to make it seem like even Newton knew that his laws of motion were bunk.

Could have been a troll, same as this current joker. Seems like lot of effort just to demonstrate Poe's Law, but people have done weirder things.

Personally I think The Flat Earth Society is a mix of people who are laughing their ass off and people who are earnest. Probably started as a joke, but once you agree to pretend to take it seriously, you'll inevitably attract people that really do believe it.

And obviously those people aren't smart enough to understand the environmental and other implications of their belief. :)

Re:Could become the final nail in Einstein's relat (2)

bondsbw (888959) | more than 2 years ago | (#37770162)

Experiment: You measure 1 meter out, and then turn 90 degrees to your right, measure 1 meter out, turn 90 degrees right, and measure 1 meter, how far will you be from the starting point? Answer: 1 meter

Similar experiment: You measure 1 km, turn 90 degrees, and do this twice more, how far will you be from the starting position? Answer: 1 km

Similar experiment: You measure 10,000 km, turn 90 degrees, and do this twice more, how far will you be from the starting position? Answer: Approx. 0 km (Why? Because the earth is nearly spherical with a circumference of around 40,000 km, and you have traversed 1/4 of that distance along 3 geodesics, leading back to your starting position.)

This is why that quote by Tesla is incorrect. You cannot assume that local flat measurements mean that space is naturally flat. It may be naturally curved. If your assumption is that the earth is flat, you might reject the third experiment. But the third experiment helps to verify that the earth is naturally round. Likewise if you assume that space is Euclidean, then you might reject large-scale measurements that seem inconsistent with local measurements. But there is the problem again: you reject measurements that are out of line with your assumptions. (In fact, a property of any Reimannian manifold is that it is smooth, meaning it is possible to "zoom in" far enough anywhere such that local measurements would be consistent with a flat manifold.)

Sorry, didn't read all the rest of your article.

Atomic? That means radiation right? (1, Funny)

Anonymous Coward | more than 2 years ago | (#37768230)

I'm not so sure that I can support anything radioactive while the poor people in Japan are dealing with their atomic disaster and remember Chernobyl? people can't live there anymore. All because of atomic clocks

Re:Atomic? That means radiation right? (1)

bmo (77928) | more than 2 years ago | (#37768294)

You know what's frightening?

Many people would actually believe you.

--
BMO

Re:Atomic? That means radiation right? (1)

Cryacin (657549) | more than 2 years ago | (#37769348)

Thankfully with this audience, you'd need an atomic clock to measure the time it would take to realise that the GP is a troll.

Re:Atomic? That means radiation right? (1)

bmo (77928) | more than 2 years ago | (#37770322)

I stand corrected.

--
BMO

Re:Atomic? That means radiation right? (1)

bmo (77928) | more than 2 years ago | (#37770708)

Wow, wrong thread.

--
BMO

Re:Atomic? That means radiation right? (0)

Anonymous Coward | more than 2 years ago | (#37773824)

Wow, wrong thread.

--
BMO

So, you stand incorrected?

Re:Atomic? That means radiation right? (0)

Doc Ruby (173196) | more than 2 years ago | (#37770850)

No, nobody would believe them. That's why they had to make it up, and get another clown to say many people would believe them.

You nuke fetishists are so desperate now that Japan nuked itself that you have to invent people to believe the BS you make up, even when that BS is against yourselves.

Re:Atomic? That means radiation right? (1)

perlchild (582235) | more than 2 years ago | (#37768568)

An atomic clock could just measure radiation as harmless as the one the sun sends out your way... every second of every day... Billions of times...

I know you were trying to be ironic, but the "it's atomic so it must be bad" just irks me.

As for energy... Solar and Fusion's the way to go, it's just more complicated to do it "Right".

We never seem to get things "right" we always stop at getting the shortcuts... and then we complain we have problems...

Re:Atomic? That means radiation right? (1)

khallow (566160) | more than 2 years ago | (#37768660)

To be safe, you probably ought to keep your sincerity in your Mom's basement until it decays into undetectable quantities, say within three days. Make it "movie weekend" and you'll have a plausible cover story.

Re:Atomic? That means radiation right? (2)

Kaenneth (82978) | more than 2 years ago | (#37770482)

You can't hug your children with Nuclear Arms.

Re:Atomic? That means radiation right? (1)

Chris Burke (6130) | more than 2 years ago | (#37774510)

You can't hug your children with Nuclear Arms.

I don't see why not -- just take your nuclear arms, gently put them around the child, and there you go. Is it because it's too difficult to make a tactical nuke small enough that the human skeleton and shoulder muscles would be able to lift it? If we're replacing the arms with nukes anyway, why not enhance the rest of the body so that it could? Seems like an engineering problem to me.

Wait, I get the feeling I'm missing something...

Re:Atomic? That means radiation right? (2)

GPF(BSOD) (871212) | more than 2 years ago | (#37777796)

But you can deliver the Mother Of All Spankings.

Re:Atomic? That means radiation right? (1)

vandamme (1893204) | more than 2 years ago | (#37832494)

Because of the mercury ions, use will be banned in the EU and California.

one word for you NASA (2)

XCDBFPL (846367) | more than 2 years ago | (#37768280)

Sundial.

Re:one word for you NASA (0)

Anonymous Coward | more than 2 years ago | (#37770172)

Comes with built in daylight savings time!

about time... (4, Interesting)

evangellydonut (203778) | more than 2 years ago | (#37768336)

Having once worked on GPS Satellite's clocking system, I was surprised that the AF was so against usage of atomic clocks phased-locked to crystals for accurate timing. Maybe the latest news about Galileo using atomic clock changed their mind?

Re:about time... (2)

kod3l (2173912) | more than 2 years ago | (#37768384)

I would assume they would want something more mechanical. Semiconductors longevity is usually not very high.

Re:about time... (3, Informative)

evangellydonut (203778) | more than 2 years ago | (#37769040)

there are plenty of Geo satellites with commercial off the shelve semiconductor parts that last 15+ years... Being in MEO and "only" lasting 12 or so years is no big deal...

Re:about time... (0)

Anonymous Coward | more than 2 years ago | (#37773088)

Not true. The rad environment at MEO is far worse than GEO. The 12-hour orbit sits in shell where the Van Allen Belts accumulate charged particles. To quote Apollo 13, it's like driving a toaster through a carwash. You get a lot of SEUs (Single Event Upsets) and particle showers. At GEO you're more exposed and you pop out of the Earth's magnetic field occasionally but it's not that constant bombardment and influx--it's seasonal. You get what the sun (and beyond) throws at you at any given moment, not the accumulation of it over time.

GPS relevence is buried at the bottom (4, Informative)

JohnnyComeLately (725958) | more than 2 years ago | (#37772070)

Were you a Payload Officer at 2 SOPS? And, are you referring to the Space or Ground segment? If you mean the backup clocks in the Mod, then that's slightly outside my knowledge. As far as the Space Segment, they've been reliably using Cesium and Rubium (atomic) clocks for over 3 decades. They don't want to change because it's known, reliable, etc. I was curious to note the newest generation of satellites dropped the 4th clock, and now launch with only 3. Since each clock is only usable a number of years (varies too much for me to generalize), I'd have thought they kept all four just in case the electrical system outlives normal design life, and you end up needing to go with a 4th clock when the 3rd one becomes too "deviant".

I think the GPS relevence is buried at the bottom of the article. Cesium and Rubidium clocks are both accurate to the nanosecond. That's just about as accurate as can be practical. The new atomic clock, however, they're saying is accurate LONGER. On GPS Satellites, the original satellites (Block I, II, IIA, IIR) launched with Cesium and Rubidium, 2 each. Usually you have one operational, sometimes one on "ready standby", and the other two off. As each atomic clock reaches the end of its mission-usable life, it's turned off. It become's "mission-unusable" (not a real term, I just made that up) when it's signal varies outside a normal window of acceptable predictability in terms of its output signal. There are design differences, such as Rubidium clocks have to stay within a tenth of a degree (F) in temperature stability (if memory serves correct). So, if they can create a clock that's more stable, for a longer period of time, this has huge potential for future GPS satellites. However, since we just awarded contract to Boeing the contract for IIF birds, with only 2 of 12 launched, it's going to be a very long time (decade at best) before you'd see this in a GPS satellite. Design life has also expanded from 7 to 12 years for each satellite (for point of reference Block I only had a design life of 3 years since they were R&D), so this pushes any usage even farther out since we're going to go longer before replacements need to be launched.

Good project.... (2)

trum4n (982031) | more than 2 years ago | (#37768382)

but it will take........TIME!!!!! Muahahahhahahaha!

Re:Good project.... (0)

Anonymous Coward | more than 2 years ago | (#37770442)

The chronophage has you.

On a related subject... (5, Informative)

Cochonou (576531) | more than 2 years ago | (#37768436)

... you might have heard about PHARAO [smsc.cnes.fr] , a caesium clock which is planned to fly on the ISS in 2013. Accuracy target is 1E-16.

ESA ACES (4, Informative)

mbone (558574) | more than 2 years ago | (#37768566)

ESA will get there first, with the Atomic Clock Ensemble in Space [esa.int] (ACES) [smsc.cnes.fr] , intended for the ISS in 2013, which should be good to ~ 10**-16 and will include a test of relativity [esa.int] . I believe that this [nasa.gov] is the JPL clock, which is aiming at 10**-15 stability, and a 2015 launch. (Both are fairly low earth orbits, with the JPL clock intended for an Iridium satellite.)

So, the JPL effort is cool, and I would love to see one flown to Mars or truly deep space, but this is one case where the Europeans are in the lead.

Re:ESA ACES (1)

mbone (558574) | more than 2 years ago | (#37768586)

Pharao is one component of ACES (see above).

More reading on [atomic] clocks (2)

martyb (196687) | more than 2 years ago | (#37769482)

Time keeping is getting better and better. I just happened upon this article recently which gives some history on timekeeping and what some of the latest efforts are working on: http://www.sciencenews.org/view/feature/id/334983/title/The_Ultimate_Clock [sciencenews.org] .

Here's an excerpt (emphasis added):

The metrology of time is not holding still. In the April-June issue of Reviews of Modern Physics, experimental physicist Hidetoshi Katori of the University of Tokyo and theorist Andrei Derevianko of the University of Nevada, Reno declared dramatic ambitions for a record-breaking atomic clock based on emissions from mercury atoms.

âoeIf someone built such a clock at the Big Bang and if such a timepiece survived the 14 billion years, then the clock would be off by no more than a mere second,â they note in the paper. That is actually conservative. The goal formally is to lose or gain no more than one out of every billion billion seconds. That is one second in about 32 billion years, and is 10 to 100 times better than any existing clocks.

PHARAO is 100x bigger than SpaceClock (1)

Anonymous Coward | more than 2 years ago | (#37769580)

There's a huge difference in size, mass, and power between PHARAO (which has impressive peformance) and the JPL DSAC/SpaceClock.
The former is 91 kg and draws 114 watts and is a meter long. The Hg+ ion clock is notionally 1 liter/1kg and a few watts.

Considering that for a deep space probe, a couple hundred kilos is the whole spacecraft and a couple hundred watts is the total power budget, that's the value of DSAC/SpaceClock.

Re:PHARAO is 100x bigger than SpaceClock (1)

mbone (558574) | more than 2 years ago | (#37775878)

You are of course quite correct. But, ACES will still fly before DSAC does, which is something.

Re:ESA ACES (0)

Anonymous Coward | more than 2 years ago | (#37770930)

3 Python too :)

Deep space? (1)

c0lo (1497653) | more than 2 years ago | (#37768618)

Deep Space Atomic Clock.... what does this have with "deep space"? GPS satellites are on medium Earth orbits [wikipedia.org] ... or did the space constricted so much now that NASA operates no shuttles?
(letting aside that... heck... what should it have anything to do with "space"? It's an atomic clock, does it need 0-g to function?)

Re:Deep space? (3, Informative)

Nyeerrmm (940927) | more than 2 years ago | (#37768706)

Its a technology demonstration for hardware that will eventually make deep space navigation better.

This is being run out of the JPL navigation section and is intended to improve long-term capabilities with a small investment.

Re:Deep space? (5, Informative)

mbone (558574) | more than 2 years ago | (#37768832)

Well, first, this is a NASA technology demonstration mission for a clock needed by JPL. That means that NASA is going to validate that this clock will work in space, so that JPL can use it where they operate (i.e., deep space, the Moon, Mars and beyond).

Second, yes, the very best modern clocks work differently with and without gravity. This is basically because the atoms used are so cold they are moving at human type velocities, and so gravity can't be ignored. The best terrestrial clocks are the fountains - take very cold atoms, moving at ~ 1 meter per second in a trap and shut off the trap. Some of the atoms (the ones that happen to be moving up) will ballistically go up, and then fall back down. (This is much like tossing your keys up 1 meter or so, and then catching them, except with single atoms.) The gravity is used to collimate the pulse of atoms going up and down, and (with timing the round trip) to select only the ultracold ones coming down. By timing the round trip, you can really select a particular set of velocities - the better constrained the velocity dispersion, the better constrained the clock read out.

NONE of that works in zero-G, and PHARAO (I am more familiar with this clock that the JPL Hg Ion one) is completely re-designed to use fountain-like ideas in a linear beam. I am not sure it would even work on the ground, and it definitely needs zero-g to meet its performance goals.

Re:Deep space? (1)

mikael (484) | more than 2 years ago | (#37769134)

Why not just put the atoms in a magnetic torus field or a circular track rather than a linear track? Seems they already use magnetic fields to sort out the atoms to get the ones in the correct phase.

Re:Deep space? (2)

mbone (558574) | more than 2 years ago | (#37769522)

Why not just put the atoms in a magnetic torus field or a circular track rather than a linear track? Seems they already use magnetic fields to sort out the atoms to get the ones in the correct phase.

You basically don't want to accelerate the atoms if you don't have to, and in a ring they would be constantly accelerating. Gravity is a little different, as it is very smooth and doesn't require contact with structure, magnetic fields, etc.

Re:Deep space? (0)

Anonymous Coward | more than 2 years ago | (#37774592)

You don't want to put the atoms in a magnetic field because that shifts the energy levels of the atoms (called the Zeeman shift). When the energy levels shift, the atom's resonant frequency shifts and the time kept by the atom will change. That is fine if you know that shift, but to know that shift at the 10^-16 level, you need to ensure you know your magnetic field to that level. And that is not possible. It's ok to apply a field when you are detecting the atoms, but it is not a good idea to apply a field when you are allowing the atoms to precess, which is what they do to keep time. On top of that, I don't see how you would make a circular path with a magnetic field that wouldn't cause all sorts of issues with state-dependent atom steering.

By the way, the sorting of atoms in fountain clocks is now done with lasers, not magnetic fields.

Re:Deep space? (2)

hjf (703092) | more than 2 years ago | (#37769634)

Deep Space clock, AKA, Pulsar [wikipedia.org] .

Re:Deep space? (1)

pclminion (145572) | more than 2 years ago | (#37781296)

The first pulsar ever discovered has a period of 1.337 seconds? That's... AWESOME.

Naturally. They need to have a Beryllium clock... (1)

Anonymous Coward | more than 2 years ago | (#37768964)

Before they can get that TARDIS project working.

Although (1)

rossdee (243626) | more than 2 years ago | (#37770254)

the deep space clock will be accurate to 1 second every umpteen million years, but will need to be reset in a couple of weeks due to the change from daylight time to standard time.

Socialism (0)

Doc Ruby (173196) | more than 2 years ago | (#37770802)

This project is clearly socialism.

If you think anything a government does is socialism.

Re:Socialism (1)

JohnnyComeLately (725958) | more than 2 years ago | (#37772102)

So you're saying this clock will pay me retirement, take care of my illnesses, repave roads, build bridges, put food on my table, educate my kids and make me coffee every morning? SWEET!!

Re:Socialism (2)

Maximum Prophet (716608) | more than 2 years ago | (#37773086)

Like most science, it won't do any of that immediately, but if it proves itself, it might make most of that better & cheaper.

Taxes pay for GPS. Farmers use GPS to track crop yield so they can fertilize more efficiently. Using high accuracy GPS to repave roads, or build bridges properly is a no-brainer. GPS might help the ambulance get to you and back to the hospital seconds *before* you're dead. So yes, a better clock can improve all those aspects of your life. SWEET!!

Re:Socialism (1)

Maximum Prophet (716608) | more than 2 years ago | (#37773132)

Not everything a government does is socialism. Some is fascism or cronyism, and let's not forget plain old waste and fraud.

(:-) for the humor impaired.

And what a surprise..Made in China (0)

Anonymous Coward | more than 2 years ago | (#37770866)

and what a surprise..Made in China. Can't wait for this one.

10 times more accurate (0)

Anonymous Coward | more than 2 years ago | (#37771852)

In related news, CERN's FTL neutrinos are only (c*1.8m) early, not 18m as measured before.

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