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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.

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The Next Falcon Heavy Will Carry the Most Powerful Atomic Clock Ever Launched

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  • by GeekWithAKnife ( 2717871 ) on Wednesday February 14, 2018 @06:06AM (#56120867)

    ...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. :-|
    • by Anonymous Coward on Wednesday February 14, 2018 @06:14AM (#56120875)

      It's going to send out such a powerful 'dong' that the whole earth will resonate in unison.

    • by Anonymous Coward on Wednesday February 14, 2018 @06:23AM (#56120891)

      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.

    • They should have gone with precise and robust.
      • [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

    • by nagora ( 177841 )

      Nothing to forgive, the headline is just bad English, although technically allowable.

      • 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.
    • ...but what does "the most powerful" atomic clock do as opposed to just a "powerful" one?

      I goes faster, of course!

      • Oh, I get it! Because it goes around the world, really fast.
        • Re: (Score:3, Informative)

          by DrTJ ( 4014489 )

          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

          • by GS1 ( 5266363 ) on Wednesday February 14, 2018 @10:31AM (#56121523)
            I believe this clock is accurate up to ±2ns per day, not per second. In fact I would be shocked if it were per second.

            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]
            • by XXongo ( 3986865 )
              Yes, atomic clocks (including the ones that support GPS) routinely incorporate the relativistic corrections-- both special and general.
              • Thanks to the people on this thread for atempting to impart some content to this otherwise content-free discussion. Science needs accurate timebases for interferometry and physics observations, among other things. Just as accurate as we can make them.
          • In this case, you have also to take into account the speed of Earth around the Sun, the speed of Sun within the Galaxy, the Galaxy within its cluster and the whole Universe is maybe moving somewhere...
          • oh and gravity has an impact on GPS ...
      • 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.

    • by dohzer ( 867770 )

      The battery will go flat faster.
      It also has a calculator function. Neat!

    • To be honest thought you guys were being way too nitpicky about the title but after reading the article I'm starting to wonder if the typewriter got stuck on those letters, in that order, somebody must have seen an early screening of Black Panther. More concerning though is that the author thinks atomic clocks are a rarity in space. I mean they were created to solve the problem of "astronomical time". That's a bit of a hint you'd think but the fact that every single navigation system satellite has several
      • 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.

    • "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.

    • by mrbester ( 200927 ) on Wednesday February 14, 2018 @08:21AM (#56121063) Homepage

      Other atomic clocks accuracy only goes up to 10. This one goes to 11. It's 1 accurater.

    • by Anonymous Coward

      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.

      • 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

    • More power, more better.

    • "Powerful" is apparently now another word for "accurate", only with more ZAZZ. (But yeah, this bugged me too)
    • 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)...

    • 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)

    • ...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.

  • by billybob2001 ( 234675 ) on Wednesday February 14, 2018 @06:48AM (#56120927)

    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.

  • by TimSSG ( 1068536 ) on Wednesday February 14, 2018 @07:05AM (#56120951)
    How did the miss this title? "The Next Falcon Heavy Will Carry the Most Powerful Time Machine Ever Launched" Tim S.
    • Seeing that Elon Musk likes to launch cars into space, maybe it will be a DeLorean.
      • Re: (Score:2, Funny)

        by Anonymous Coward

        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.

  • by Viol8 ( 599362 ) on Wednesday February 14, 2018 @07:28AM (#56120981) Homepage

    ... 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.

  • by 140Mandak262Jamuna ( 970587 ) on Wednesday February 14, 2018 @07:35AM (#56120995) Journal
    I am sure it would be carried aloft by the most accurate rocket.
  • Finally my master plan to destroy all of time will be realised!
  • by andrewbaldwin ( 442273 ) on Wednesday February 14, 2018 @08:21AM (#56121067)

    ...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.

    • The wave harmonic theory of historical perception, in its simplest form, states that history is an illusion caused by the passage of time, and that time is an illusion caused by the passage of history.
  • The article doesn't explain how knowing what time it is tells the clock WHERE it is

    Orbital failure

    It was exact 00:00.999891 when I slammed into the target

    • As long as you know the time precisely you can calculate your location using observations of solar system objects. It works a lot like marine navigation of olde, development of marine chronometer was a major advancement then too.
    • 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

      • It would seem that with this clock the probe would receive a time signal from Earth and directly calculate its distance itself.

      • by shayd2 ( 1689926 )
        it's been traveling along this map for this duration at this speed ...

        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

    • 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.

  • Neither the summary nor the title give any indication how much power this clock dissipates. 10kW? 100kW? How does this compare to previous atomic clocks? How will it be powered? These are questions we need answers to!
  • Soon you'll be able to course correct satellites right into the ground.

  • Forget the Falcon Heavy; I can't wait for the next F**kin Heavy [youtu.be]launch!

    • by quenda ( 644621 )

      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.

      • Sometimes a Falcon is just a Falcon.

        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?

        • by quenda ( 644621 )

          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.

  • I could not find any mention of horsepower, voltage, current, political influence, or anything that would substantiate "most powerful atomic clock"?

  • After all the Luddites protesting at the Cassini launch, I wonder how many this will attract?

  • 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?

    • by sl3xd ( 111641 )

      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.

Prototype designs always work. -- Don Vonada