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NASA Scientists Get Custom 24h39m-per-day Watches
blair1q writes "In order to more easily keep solar time on Mars, (or maybe just as a lark) JPL has ordered specially-modified mechanical watches for the Mars Exploration Rover Mission. One wonders why these literal rocket scientists didn't just get a software programmable Linux or PalmOS based wrist-computer and hack together a Mars-time display application into it?"
You can have one! Just not yet, and who knows at what cost...
After he accommodates all rover team members who wish to own a custom-made Mars watch, he will market his patented rarity to the public.
If I had a spare couple of grand (they'd have to cost at least that, given they're custom-modified mechanical watches), I'd seriously consider one.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
--Carlos V.
If you want digital, these folks make most of the watch crystals out there. It would be a small order to get digital watches to run at any speed. I've ordered custom crystals for radio's from them. Small orders are no problem and they are not expensive.
http://www.icmfg.com/
A standard Tera Firma digital watch crystal frequency is 32.768 kHz.
They are listed here.
http://www.icmfg.com/surfacemount_crystals.html
It would be a small task to get custom crystals made for the Martian day from them for your watch. You may need SMD tools to change it.
At the bottom of the page gives informatin for ordering non standard frequencies.
IMPORTANT: When ordering any non-standard crystals, please specify series or parallel resonance. If parallel, the load capacitance (CL) needs to be specifed in picofarads___ pF. All specifications are subject to change without notice.
The truth shall set you free!
In the FA:
Urban legend, yes. The US used pencils too, or felt markers (which also work just fine in zero gravity). Then Fischer spent millions of their own cash designing the Space Pen, and sold them at a nominal rate to NASA for the publicity.
"I Know You Are But What Am I?"
Claim: NASA spent millions of dollars developing an "astronaut pen" which would work in outer space while the Soviets solved the same problem by simply using pencils.
Status: False.
>[electronic watches] won't last nearly as long: they'll either get wet, simply stop working, or wear out electronically long before a Rolex begins to stop keeping the correct time.
N.B.: Among watch afficionadoes, Rolex is something of a joke, mostly because they don't keep time nearly as well as equivalently-priced watches from less-widely-marketed makers (International Watch Co., Breitling, et al), and partly because of the enormous number of counterfeit Rolexen in the wild.
And, in case anyone's wondering, the original Moon watch is the Omega Speedmaster Professional.
Looks like someone has already set up a whole Website (section) for ordering it:
http://executivejewelers.com/mars/
Comes up quite high with relevant Google searches...
Windows only, but there is this one
When engineers could build something without using anything that had been compiled.
paintball
It is not very impressive. In a mechanical watch is a balance wheel and a hair spring. The wheel and spring are oscilating (that is making a mechanical watch tick). The Oscilation period is the time base for the watch. You can change the oscilation period by altering the mass of the balance wheel (adding weight makes the oscilation period longer) or changing the spring constant of the hair spring (make it less stiff or langer for a longer oscilation period).
The formula for the oscillation time is
T = 2*pi*sqrt(J/k)
with
J = moment of inertia
k = the spring constant.
It looks like the watches have added weight on de balance wheel. He did a naice job but it is not earth (or mars) shattering.
Nyh
Q: "Two wonder why these literal rocket scientists need to know what time it is..."
A: To effectively make use of communications passes with orbital spacecraft such as Mars Global Surveyor.
Q: "Three wonder why these literal rocket scientists don't just have really big clocks on the wall..."
A: We do.
Regards,
Space Cowboy
OK, for all you dumbfucks that can't be bothered to think:
The Mars team are working on the Martian day, as they can only talk to the lander at certain times of (Martian) day, and it's rather nice if your team is awake when you do so.
Most of them, unlike typical slashdot readers, have wives, families and lives, and don't spend 24 hours an (Earth) day looking at their computers.
A Mars watch means that it's easy to look at the time and think "2 hours till we can talk to the lander - time to go to work"
Oh, and there's all the psychological reasons - having a wristwatch makes it easier to adapt to the martian day.
I also have a spacepen. And it sounds like you have a lemon.
Mine has been idle for years (since I got a keyboard) and it works like the day I got it.
Upside down and underwater no less.
---Up Up Down Down Left Right Left Right B A START
Done and done.
There is a palm version out there, too, though, IMHO, it doesn't work all that well. Or, more accurately, it doesn't meet the standard set by this program.
One wonders why these literal rocket scientists didn't just get a software programmable Linux or PalmOS based wrist-computer and hack together a Mars-time display application into it?"
I did: MarsClock
Space and Computers.
There could actually be a rational reason why these watches might improve mission reliability, and thus save money. One of the main problems with earth ground system operations is the ability of the ground staff to operate in several time zones at the same time. Although the ground system is (typically) on ZULU (or GMT), their shift patterns run on local time, and often the planning cycles (passes etc) operate at on offset from GMT. An example is the ROSAT day, or the RADARSAT planning offset, which is set off 19 hours later than GMT, thus the start of the RADASAT day is at GMT 19:00 and extends 24 hours to 19:00 the next day. Further, the antennae are scattered around the globe, and the antennae ground staff also operate their shift patterns on local time (they have a life outside the blockhouse) but run passes on ZULU time. These can be quite confusing, and a lot of planning screw ups (running passes on the wrong day etc) can result. If this gets out of hand, the wrong command can get sent at a bad time and that's that, everybody is suddenly unemployed! As Mars rover is (essentially) an automated MARS based ground system, perhaps these watches are an attempt to get better organized? Or maybe they are a status gimmick.
I stole this
I found one that said Rolexxx -- ended up sitting there for a half hour arguing with the guy that since it was a fake he should sell it to me for $5...or I would continue to ruin sales (which I did as folks came by)...I got it for $7.50 (which is what the guy claimed he paid for it) to get me out of there :-)
I'll be sad the day I stop in NYC and find out the patriot act or whatever has taken these guys off the streets...*EVERYONE* knows they are fakes...a least the ones with half a brain in their head, but you gotta admit, for even $20, they make the best cheap watches you'll ever find. I'd pick one of these up over anything I could find at the local discount retailers...the fact that they blatently try to rip off the names of high society jewlery is just an added bonus.
I gave one of these as a Christmas present to a friend and TOLD him it was a fake...he claims it was one of the best gifts he'd gotten that year and enjoys it for the subversiveness of it...
Hacking a digital watch is nontrivial, especially if you have the same size and power consumption requirements as the original watch. The power budget of digital watches is austere, to say the least; typical drain of the entire watch, including oscillator, divider chain, and display driver, is 500 nA at 1.5 V, or 750 nW (a nanowatt is one billionth of a Watt).
Watches use 32.768 kHz AT-strip (tuning fork-style) quartz crystals (like these) as a compromise between size and low power consumption. The smaller the size of a crystal operating in a given mode of oscillation, the higher the frequency of oscillation. However, the power consumption of a digital switching circuit increases directly with the switching frequency (it is P (Watts) = CV^2f, where C is the capacitance of the switching device in Farads, V is the difference in volts between a logical 1 and a logical 0, and f is the frequency of switching in Hz). Having a higher oscillation frequency requires a longer frequency divider to divide the oscillator's output down to the required 1 Hz output, which raises the power consumption of the divider (mostly due to the higher switching frequency of the first few stages).
Having the crystal oscillate at a binary multiple of the desired output (32768 = 2^15) makes the divider circuits especially simple (15 divide-by-two stages in series). Having a non-binary multiple would require more switching circuitry and add to power consumption.
To hack such a system to Mars time would require either changing the crystal frequency or the divider string. Changing the divider string would require modifying the watch chip, a design task that would be relatively simple, digital design tools being what they are, but expensive and time-consuming, since a new IC mask set would have to be generated and a new lot of chips run through the fab--say, $250k and 3-6 months, if you started today. Not very desirable if you're a JPL guy funding this out of your own pocket (which is how this was done).
The alternative is to modify the crystal frequency. AT-strip tuning-fork watch crystals are cheap because they're made in a lithographic manner not dissimilar to that of IC production--a mask is made, resist is printed over a quartz blank, the blank is etched, etc. This produces nearly-identical parts in bulk, making them cheap. This is different from the standard AT-cut crystals with which most amateurs are familiar; AT-cut crystals are individually cut and polished to frequency. Since AT-strip crystals are made in bulk, one cannot get a small lot of them inexpensively, as one can AT-cut crystals; the manufacturer must make a new mask set for the new frequency, a relatively expensive task if one will only purchase, say, a hundred crystals. Modifying the crystal frequency is less expensive than making a new watch chip; however, neither option is suitable for the volumes and price points the JPL guys were trying to hit. Ergo, the mechanical watch.
Indeed. The software we used to command both rovers during cruise is written in Java (I wrote it!); we're using the same software to command them on the surface as well. (The surface commanding is actually done with an integrated mix of software -- my half is in Java; the other half, the 3-D visualization stuff, is in C++. We also have various kinds of links to other JPL applications, most of which are written in C or C++.)
And no, this isn't Maestro (a.k.a. SAP) I'm speaking of. But Java is an important part of this mission, as is Linux.
Oh, and just so I can be on-topic: everyone who wants a Mars-time watch pays for it out of his own pocket. I'm cheap, so I'm using the nifty MarsClock application on my Palm, as well as a GNOME panel applet I wrote myself that displays UTC and Mars time. We also have big electronic whiteboards that display UTC, PST, and Mars times (and the app that does this is written in Java). But I might get a Mars watch anyway, as a souvenir if nothing else.
``Life results from the non-random survival of randomly varying replicators.'' -- Richard Dawkins
Really? I could've sworn it was capillary action.
Pencils = graphite shavings floating around and getting into instrumentation = bad and not used (regular pens should work fine in outer space)
False parts:
1. The part about NASA spending millions of dollars to develop the Space Pen. NASA *didn't* develop it, a private company did.
2. The part about NASA wasting taxpayer dollars on the Space Pen. NASA didn't spend very much to acquire those that they did use from the manufacturer, so no waste of taxpayer dollars here.
3. The part about the Russians using pencils, but NASA only using an expensive Space Pen. NASA used pencils too, as well as inexpensive felt tip markers.
So, in short, pretty much all of the parts of the standard urban legend version of events are false.
In addition, there are very real reasons to want to avoid using a pencil, not the least of which is what do with the shavings as well any snapped points floating around the capsule.
Never confuse volume with power.
--Check the http://executivejewelers.com/mars/ site, they're going for $145 (Orient model) and up. They are apparently brand-name watches *adapted* to Mars time, instead of being hand-made from the ground up.
.
== WolfriderV6 == I'm willing to admit that *I just might* be wrong... Are you??
Keep in mind that these guys need much more precision than your average joe, kinda like the railmen back in the day. It's not like they can tell the rover to get up at eleven-thirty-ish, wander over to that dune and shoot us back an e-mail. If they're a few seconds off they'll end up talking to the elvis-face instead of the mars rover.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Because that suggestion is stupid.
Manipulate the moderator system! Mod someone as "overrated" today.
More precisely, they rely on a mass oscillating under the influence of a spring. That mass (and its associated moment of inertia) stays fixed regardless of the gravity field you're in (or in freefall, as in orbit). The same goes for the important properties of the spring (within any reasonable gravity field.)
Watches are not gravity dependent--otherwise, you'd be in trouble if you held your arm the wrong way. Pendulum clocks, on the other hand, are very much dependent on gravity--their weight is quite important.
$5 quartz watches still work by giving a quartz crystal juice and dividing its constant Hz by some number to keep time, correct?
Correct, and a quartz oscillator and custom circuitry would certainly produce a perfectly serviceable watch for this purpose. Unfortunately, the minimum lot size for such custom work (as mentioned in the article) is ten thousand units--many more than JPL was anticipating a need for.
~Idarubicin
remember these are the same geniuses who spent millions of dollars to design a pen that could write in zero G. Did you know what the Soviets did? they used pencils!