Slashdot Mirror
The Next Falcon Heavy Will Carry the Most Powerful Atomic Clock Ever Launched (space.com)
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.
...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.
A 'singular oddity' is an event that cannot be explained and only happens when you are alone.
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.
How did the miss this title? "The Next Falcon Heavy Will Carry the Most Powerful Time Machine Ever Launched" Tim S.
... 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.
I am sure it would be carried aloft by the most accurate rocket.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
There are many atomic clocks in space already. Just the satellite positioning systems alone adds up to more than 100 clocks.
...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.
Orbital failure
It was exact 00:00.999891 when I slammed into the target
Shirley if it has a powerful dong it should be used to time porn films?
You don't compensate for it. You want accurate time measurement within the orbiting clock's frame of reference. The value comes from comparing it to other clocks in their respective frames of reference. A translation between frames of reference can be done to take advantage of the accuracy of whatever is considered to be the most accurate clock.
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.
I'll see your senator, and I'll raise you two judges.
Seeing that Elon Musk likes to launch cars into space, maybe it will be a DeLorean.
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.