The Next Falcon Heavy Will Carry the Most Powerful Atomic Clock Ever Launched (space.com) 128
schwit1 shares a report from Space.com: This isn't your average timekeeper. The so-called Deep Space Atomic Clock (DSAC) is far smaller than Earth-bound atomic clocks, far more precise than the handful of other space-bound atomic clocks, and more resilient against the stresses of space travel than any clock ever made. According to a NASA statement, it's expected to lose no more than 2 nanoseconds (2 billionths of a second) over the course of a day. That comes to about 7 millionths of a second over the course of a decade. n an email to Live Science, Andrew Good, a Jet Propulsion Laboratory representative, said the first DSAC will hitch a ride on the second Falcon Heavy launch, scheduled for June.
Every deep-space mission that makes course corrections needs to send signals to ground stations on Earth. Those ground stations rely on atomic clocks to measure just how long those signals took to arrive, which allows them to locate the spacecrafts position down to the meter in the vast vacuum. They then send signals back, telling the craft where they are and where to go next. Thats a cumbersome process, and it means any given ground station can support only one spacecraft at a time. The goal of DSAC, according to a NASA fact sheet, is to allow spacecraft to make precise timing measurements onboard a spacecraft, without waiting for information from Earth. A DSAC-equipped spacecraft, according to NASAs statement, could calculate time without waiting for measurements from Earth -- allowing it to make course adjustments or perform precision science experiments without pausing to turn its antennas earthward and waiting for a reply.
Every deep-space mission that makes course corrections needs to send signals to ground stations on Earth. Those ground stations rely on atomic clocks to measure just how long those signals took to arrive, which allows them to locate the spacecrafts position down to the meter in the vast vacuum. They then send signals back, telling the craft where they are and where to go next. Thats a cumbersome process, and it means any given ground station can support only one spacecraft at a time. The goal of DSAC, according to a NASA fact sheet, is to allow spacecraft to make precise timing measurements onboard a spacecraft, without waiting for information from Earth. A DSAC-equipped spacecraft, according to NASAs statement, could calculate time without waiting for measurements from Earth -- allowing it to make course adjustments or perform precision science experiments without pausing to turn its antennas earthward and waiting for a reply.
Forgive my ignorance (Score:3, Insightful)
...but what does "the most powerful" atomic clock do as opposed to just a "powerful" one?
"powerful" is not something I can immediately quantify when it comes to time keeping.
Re: Forgive my ignorance (Score:5, Funny)
It's going to send out such a powerful 'dong' that the whole earth will resonate in unison.
Hmm (Score:3)
Shirley if it has a powerful dong it should be used to time porn films?
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DickBreath's Law: Any background music used in pr0n films is interchangeable with background music for Power Point presentations.
Well that certainly explains an embarrassing reaction of mine at the last briefing.
Re:Hmm (Score:5, Funny)
Not just no, but...no. And stop calling me Shirley....
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A powerful dong with a small DSAC? Is that what happens when a steroid junkie takes a lot of viagra?
Re: Forgive my ignorance (Score:1)
huh, I'm guessing it's not using NTP then?
Re:Forgive my ignorance (Score:5, Informative)
You need to think of power like a superhero's power. From the Oxford Dictionaries website the first definition of power is: The ability or capacity to do something or act in a particular way.
Obviously, an atomic clock's power is to measure time accurately using atomic behavior. So this is indeed the most powerful atomic clock launched.
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It's going to shoot the most powerful "Arrow of Time" ever!
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[powerful?!]
They should have gone with precise and robust.
Or "accurate".
Even though "precise" (measures intervals well) is more correct than "accurate" (closeness to the standard, i.e. both precise and properly set), when you're getting technical, it's in more common use and gets the meaning across a lot better than "powerful".)
When I hear "powerful" I get "this thing uses a lot of power". NOT what you want in an instrument on a spacecraft.
(Reminds me of a satire of golden age science fiction, where the a
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Nothing to forgive, the headline is just bad English, although technically allowable.
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It's probably the most allowable bad English headline...is this what Trump would call "Fake English"?
I intend to help fund the centre for kids who can't read good and cannot do other stuff good too.
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...but what does "the most powerful" atomic clock do as opposed to just a "powerful" one?
I goes faster, of course!
Duh.
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Oh, I get it! Because it goes around the world, really fast.
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But this is actually relevant (well, almost)!
I don't know the orbital speed of this clock, but if it goes as fast as ISS, it's about 8 km/s.
The time dilation relative to an earth observer will be approximately
t/t' = 1/sqrt(1-v^2/c^2) = 1/sqrt(1-(8/300000)^2) ~ 1.000000000355
That corresponds to 0.355 ns per second, so if the expected drift is ~2 ns/s, they are actually homing in to the relativistic limit for how much two observers can agree on in this setting. I.e. it would be kind of pointless to make it 10
Re:Forgive my ignorance (Score:5, Informative)
Plus, this has to be understood as a random walk of time keeping. When a clock "looses" a second, it's not necessarily slower than some other reference. It may be faster.
Now, if relativity states time dilation slows clocks (from the point of view of Earth-based observers), this is something we can agree upon and take into account. This is not clock imprecision of random loss (or gain) of time. It has in fact and must be taken into account for the GPS system to work at all.
See: https://physics.stackexchange.... [stackexchange.com]
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Think of atomic clocks as time machines that transport observers to a very specific time in the present. This one is more powerful, so it is better at transporting the observer to the present than previous versions.
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The battery will go flat faster.
It also has a calculator function. Neat!
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The idea is to use them on interplanetary spacecraft, where atomic clocks are much rarer. When a spacecraft is several lightminutes away, getting the clocks synced and navigation commands sent, received and confirmed is much more challenging than doing the same in LEO or GEO. By having that accurate of a clock on our spacecraft they can eliminate the sync portion.
Having that precision on GPS would be a boon to robotic vehicles as well.
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"powerful" is not something I can immediately quantify when it comes to time keeping. :-|
It has a Dr. Who inside.
Jodie Whittaker has complained that Apple's newest update slowed her down.
Re:Forgive my ignorance (Score:5, Funny)
Other atomic clocks accuracy only goes up to 10. This one goes to 11. It's 1 accurater.
Re:Forgive my ignorance (Score:5, Funny)
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"Other atomic clocks accuracy..."
My Swatch clock goes up to 999.
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And my microwave oven goes to 99:99
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Per the summary, this clock is meant to drift by no more than 2 nanoseconds per day. Current GPS clocks drift by 10 nanoseconds per day (ref [theconversation.com]). So this clock can tell you the time with an uncertainty one-fifth that of current space-based clocks.
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Furthermore the NASA article states that this is a prototype mercury ion trap clock that is expected to reach an accuracy of 0.3 nanoseconds a day with some more refinement, which will make it 30 times as precise as GPS satellite clocks.
The stability of this clock is at least 2E-14, and the future version will be 3.5E-15. For comparison the US national standard clocks (NIST-F1 and NIST-F2) has a stability of about 1E-16, so this is pretty darn good for compact, low energy consumption, system for long term u
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More power, more better.
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Too Trump-like... (Score:2)
Makes me think of how Trump exaggerates things: This is the most powerful clock (hand waving)...it's the best clock (gun gesture)...you'll see how good it is (hand going in circles)...
Most powerful atomic clock (Score:2)
This new atomic clock has a yield of 10.4 megatons (over 450 times more powerful than the bomb dropped on Nagasaki during World War II)
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...but what does "the most powerful" atomic clock do as opposed to just a "powerful" one? "powerful" is not something I can immediately quantify when it comes to time keeping. :-|
Essentially, everything you think you understand about clocks is wrong. Clocks don't measure time... they actually warp the fabric around what the clock face shows, hence, a more powerful clock is capable of warping time more accurately and/or over a wider area.
Most powerful... 13? (Score:5, Funny)
Nigel Tufnel: The numbers all go to thirteen. Look, right across the board, thirteen, thirteen, thirteen and...
Marty DiBergi: Oh, I see. And most clocks go up to twelve?
Nigel Tufnel: Exactly.
Marty DiBergi: Does that mean it's timelier? Is it any timelier?
Nigel Tufnel: Well, it's one timelier, isn't it? It's not twelve. You see, most blokes, you know, will be timing at twelve. You're on twelve here, all the way up, all the way up, all the way up, you're on twelve on your craft. Where can you go from there? Where?
Marty DiBergi: I don't know.
Nigel Tufnel: Nowhere. Exactly. What we do is, if we need that extra push over the event horizon, you know what we do?
Marty DiBergi: Put it up to thirteen.
Nigel Tufnel: Thirteen. Exactly. One timelier.
Marty DiBergi: Why don't you just make twelve timelier and make twelve be the top number and make that a little timelier?
Nigel Tufnel: [pause] These go to thirteen.
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Excellent... if only we could get the moderation to go to 6.
Re:Most powerful... 13? (Score:5, Funny)
Excellent... if only we could get the moderation to go to 6.
Yes! The post could then be modlier!
Woot!
... Will Carry the Most Powerful Time Machine ... (Score:3, Funny)
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Seeing that Elon Musk likes to launch cars into space, maybe it will be a DeLorean.
They've tested this several times. But every time the rocket gets to 88 mph, the DeLorean disappears.
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There are many atomic clocks in space already. Just the satellite positioning systems alone adds up to more than 100 clocks.
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I wonder how long before some CND halfwit... (Score:5, Funny)
... reads "atomic" and starts River Dance style knee jerking and protests against it. Until one of his compatriots who was assigned the working braincell for the day points out his mistake to him.
Powerful Clock! (Score:5, Funny)
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Precisely!
MUHAHAHAHAHA (Score:1)
Time is an illusion (Score:3)
...lunchtime doubly so.
Ford Prefect (or rather his creator, Douglas Adams) was not entirely flippant.
I'm sure much brighter people than I have addressed this but it would be nice to know what the time is measured against / where is the datum.
In 'normal life' any discrepancies caused by the relative motion of clock and observer can be ignored - they're too small an Newtonian mechanics is fine.
However even at low earth orbit conditions, GPS satellites and receivers need to make relatavistic adjustments.
When we're measuring to such (almost incredible) levels of detail and talking about movements in various gravity wells surely an agreed well defined datum is required otherwise how can any sensible measure be taken.
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As has been said before, time is Her way of keeping everything from happening all at once.
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This is well known and already compensated for in GPS (it must be, or GPS would not work).
Re:Gravitational time dilation (Score:4, Informative)
On the subject of accuracy, about that 7 microseconds per decade -- does that assume that all errors accumulate in the same direction? Or might some oscillation errors be in different directions from other errors. (eg, an extra "tick" or a missing "tick".)
Even if all errors accumulate in the same direction, it is probably not enough for slow, inefficient, puny humans to notice. The length of sprints do not need to be adjusted to compensate, and thus no effect on the release schedule.
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On the subject of accuracy, about that 7 microseconds per decade -- does that assume that all errors accumulate in the same direction? Or might some oscillation errors be in different directions from other errors. (eg, an extra "tick" or a missing "tick".)
All such x number of fractional seconds per mega-fortnight or what-have-you is a way of expression the stability by multiplying the "mega-fortnight" by the stability factor (1E-15, 3E-16 and so on) for public consumption. You are right that these errors are random walks (otherwise they could be compensated for) and that the actual drift with time will be significantly smaller.
Uncertainty principle (Score:2)
Orbital failure
It was exact 00:00.999891 when I slammed into the target
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I think it's using dead reckoning: It's been travelling along this map for this duration at this speed, so it must be at point X. That means it must have a way of determining it's speed: Magnetic and gravity fields, perhaps.
You have it rather backwards, the distance they know accurately from direct measurement using the time signal transmitted. Speed can be obtained as a derived quantity, the distance at two different times. But they can also measure speed directly via the doppler shift (this is probably only done Earthside).
The position in the sky (providing the other two coordinates required for a complete position and velocity solution) is determined from Earth by a combination of time signal differences (just like with GPS
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The satellite doesn't need to know where it it, that's the reciever's job. You compare the time difference of arrival from 3 or more satellites, and the GPS receiver determines where it is from that. The ground control system keeps track of where the satellites are at for navigation purposes and to keep them in orbit, but the atomic clock for the GPS time signal doesn't keep track of where the satellite is at, specifically - it just broadcasts it out. Others do the "where am I" (or "you") calculations ex
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It would seem that with this clock the probe would receive a time signal from Earth and directly calculate its distance itself.
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If clock carrier knows precisely what map it is following, there wouldn't be a need for course corrections.
Locating 3D position won't work very well if the clock is in the Kupier belt and the satellites are close to the sun
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The spacecraft uses the clock to tell the Earth station exactly what time it sent the signal, we know what time we received the signal and therefore know how far away it is to +- 1m. With the new clock we don't have to worry about keeping the clocks synchronized like we do with the current clock. The new clock is being tested for interplanetary vehicles, with use in GPS satellites is a side benefit.
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If you want something more accurate than internet-based NTP, you can try: Your own Stratum-1 NTP server [ntpsec.org] (it's fun, do it!).
This lets you connect a GPIO pin of a Raspberry Pi directly to the Pulse Per Second pin of a GPS receiver (which receives the signal from multiple satellites simultaneously, and each has multiple atomic clocks. GPS, GLONASS, Galileo, Baidu...) The receiver I use typically sees at least 15 satellites, which isn't too hard when there are four constellations in various stages of completene
So how powerful is it? (Score:2)
That'll be interesting (Score:2)
Soon you'll be able to course correct satellites right into the ground.
Did anyone else hear "F**Kin Heavy"? (Score:2)
Forget the Falcon Heavy; I can't wait for the next F**kin Heavy [youtu.be]launch!
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No, you must be thinking of the new rocket under development, the BFR, which takes its name from the Big Fucking Gun in Doom games.
Sometimes a Falcon is just a Falcon.
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But is it? The next project is the Big Falcon Rocket, and we all know what that sounds like. Did Musk pick "Falcon" so he could set that up sometime? It's a perfectly good rocket name, distinctive and giving the impression of speed and power, but is that all that it is?
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Did Musk pick "Falcon" so he could set that up sometime?
I did consider that. Seems possible, but more likely just a coincidence, conveniently allowing the early internal 'bfr' codename to be retained for polite usage.
Would Musk really have chosen his rocket name in order to make a weak double entendre on an obscure element of an old video game?
He says it is named after the Millennium Falcon.
Post Powerful Atomic Clock Ever Launched (Score:2)
Powerful? (Score:2)
I could not find any mention of horsepower, voltage, current, political influence, or anything that would substantiate "most powerful atomic clock"?
Anti-nuclear protests (Score:2)
After all the Luddites protesting at the Cassini launch, I wonder how many this will attract?
Whose 2 ns? (Score:2)
It would seem that there's a lot of ambiguity in this clock. If you're looking at 2ns per day, then the orbital speed will have relativistic effects, not including the distance from earth as well. So who is this keeping time for?
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It's mostly for navigation.
Even 18th century celestial navigation was dependent on accurate clocks [wikipedia.org] - Then, as now, a more accurate clock gives you a more accurate location.
Relativistic effects are important, and the GPS system uses all of them (as does its siblings).
GPS Satellites subtract 45 microseconds per day due to their position high above Earth's magnetic field, and then add back 7 microseconds due to their orbital velocity -- making a rough 38 microsecond/day correction.
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Earth's magnetic field
Yeah, I meant to say gravitational field. Sorry.
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Zaphod Beeblebrox never had a problem with that.
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The People elected him; people are a problem.