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Computer Date Glitch May Limit Next Shuttle Launch

ScuttleMonkey posted more than 7 years ago | from the 1999-called-they-want-their-date-bugs-back dept.

354

n3hat writes "Reuters reports that the next Space Shuttle mission may have to be deferred if it gets too close to the New Year because the onboard computers do not handle the changing of the date in the same way as the ground computers. From the article: '"The shuttle computers were never envisioned to fly through a year-end changeover," space shuttle program manager Wayne Hale told a briefing. The problem, according to Hale, is that the shuttle's computers do not reset to day one, as ground-based systems that support shuttle navigation do. Instead, after December 31, the 365th day of the year, shuttle computers figure January 1 is just day 366."

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354 comments

How Many Times? (2, Interesting)

Anonymous Coward | more than 7 years ago | (#16747157)

How many times is this going to bite us in the ass? Ada solves all these sorts of problems, and soooo many of my tax dollars went into its creation? I understand that the space shuttle is a limited platform, but why aren't any of the lessons learned in Ada being applied?

Re:How Many Times? (0)

Anonymous Coward | more than 7 years ago | (#16747167)

loldongs

Re:How Many Times? (0)

Anonymous Coward | more than 7 years ago | (#16747271)

This sounds like some kind of conspiracy theory from some fringe group.
How can you keep track of the date and time, and have it screw up at the New Year?
Well I better start buying bottled water because they are putting drugs in the water to dumb down all of us.

Is there anybody else selling a bridge today?

Sue
When it's time,
It's time,
And it may be sooner then you think.

lame (0, Redundant)

the_mastermind0 (1013971) | more than 7 years ago | (#16747165)

How lame is that? Millions of dollars put into a shuttle and it can't even interpret the date correctly. Might as well just plug in my cell phone.

Re:lame (2, Funny)

RuBLed (995686) | more than 7 years ago | (#16747375)

Well we know that programmers get confused with numbers one time or another since we're used to start things at index 0. The shuttle's programmer must have left an extra ctr++ there :)

(or maybe he watched too much Star Trek that he thought he should follow the intergalactical star dates)

Re:lame (4, Funny)

morgan_greywolf (835522) | more than 7 years ago | (#16747445)

(or maybe he watched too much Star Trek that he thought he should follow the intergalactical star dates)


Oh, shit! You mean we're not supposed to be following intergalactic star dates?? No wonder those programs I wrote have so many date bugs...

   

Re:lame (4, Funny)

ozmanjusri (601766) | more than 7 years ago | (#16747825)

Well we know that programmers get confused with numbers one time or another since we're used to start things at index 0.

Nah, everyone knows geeks are useless at dates because they never get any. Predictable failure, that one.

Re:lame (1)

russellh (547685) | more than 7 years ago | (#16747821)

How lame is that? Millions of dollars put into a shuttle and it can't even interpret the date correctly. Might as well just plug in my cell phone.
reminds me of the windows daylight savings time bug [codeproject.com] which I just ran into a few months ago. millions of dollars and microsoft can't get dates right either.

This story is obviously bogus... (2, Interesting)

drooling-dog (189103) | more than 7 years ago | (#16747857)

...and I'm surprised that so many of the techie gurus around here are buying it.

wtf? (4, Funny)

PhrostyMcByte (589271) | more than 7 years ago | (#16747175)

Is there a reason these aren't built on standard parts and operating systems? If they ran their shuttles on something like Debian stable it would be a rock solid platform and probably end up saving them lots of money. Or am I missing something here.

Re:wtf? (4, Funny)

jbrader (697703) | more than 7 years ago | (#16747211)

Is there a reason these aren't built on standard parts and operating systems?

It was built by the government.

Re:wtf? (2, Insightful)

Agelmar (205181) | more than 7 years ago | (#16747809)

Actually, if you want to be correct, it was built for the Government. There's a difference - rather than building a piece of crap using underpaid (government) labor, we paid top dollar so that it could get subcontracted out multiple levels, while still winding up with the same crap.

Re:wtf? (0)

Anonymous Coward | more than 7 years ago | (#16747217)

Linux did not exist in the 70s.

Re:wtf? (4, Insightful)

schnikies79 (788746) | more than 7 years ago | (#16747247)

your idea of rock solid and their idea is little different. they have probably one of the most bug-free pieces of software in existence. it's tailored to do what it needs to do, nothing more, nothing less and it does it perfectly.

Re:wtf? (4, Insightful)

Anonymous Coward | more than 7 years ago | (#16747269)

Bug free except for the rollover to a new year...

Re:wtf? (1)

dhasenan (758719) | more than 7 years ago | (#16747457)

Which suggests a workaround: Set the computers to June rather than December.

There are issues with this, of course--mainly, if lunar gravity is significant, then calculating it requires knowledge of its current position, which can be calculated based on the date (presumably). In which case you need to find an equivalent lunar period that doesn't fall on New Year's.

Still, it should be possible to update the code to handle the date issue, without much trouble.

Re:wtf? (1)

T-Ranger (10520) | more than 7 years ago | (#16747513)

Which would be a problem only if they wire-wrapped in the gravity/time tables. Just update those, too.

Re:wtf? (2, Interesting)

Firehed (942385) | more than 7 years ago | (#16747575)

Or just let the thing call Jan 1 '07 'day 366, 2006' and have the boys in the funny suits wear watches.

You'd think someone at NASA could just do the five-second fix and be done with it though. It's, what, three lines of code?

Big hint, NASA:
while ($day >= 366)
{
  $year++;
  $day -= 365;
}

Re:wtf? (2, Insightful)

lnjasdpppun (625899) | more than 7 years ago | (#16747639)

And leap years? And anything else neither you nor I have thought of?

I suspect they don't do a 5-second fix up because it's a space shuttle and they do far more testing and documentation for their code than any other project in existence.

Re:wtf? (1)

joe90 (48497) | more than 7 years ago | (#16747561)

If you RTFA, it seems to have been a design decision, rather than a bug per se. Just because something isn't present in an application, it doesn't necessarily mean it's a bug.

IIRC, software design for the space shuttle is somewhat detailed, so I don't think something like the date functionality is anything but a deliberate design decision.

Re:wtf? (1)

Joebert (946227) | more than 7 years ago | (#16747949)

Bug free except for the rollover to a new year...

Why can't the programmers at T-Mobile leave bugs like that ?

Re:wtf? (2)

moosesocks (264553) | more than 7 years ago | (#16747275)

Uhm. I think the whole point of this article is that it doesn't do it perfectly.

That said, I'll agree that NASA's software is certainly a heck of a lot more stable than Debian. After all, this is rocket science.

Re:wtf? (1)

Andy Gardner (850877) | more than 7 years ago | (#16747465)

they have probably one of the most bug-free pieces of software in existence.

Ahh, so this must just be an unexpected feature...

Re:wtf? (1)

morgan_greywolf (835522) | more than 7 years ago | (#16747617)

your idea of rock solid and their idea is little different. they have probably one of the most bug-free pieces of software in existence. it's tailored to do what it needs to do, nothing more, nothing less and it does it perfectly.


Actually, that's not entirely true. The space shuttle's main computer is called the GPC -- General Purpose Computer. Among other things it controls avionics and a whole bunch of ther systems -- it's not really a dedicated-purpose computer as one might think.

Re:wtf? (0)

Anonymous Coward | more than 7 years ago | (#16747279)

tandard parts and Operating systems.... You mean like Windows 98?

Re:wtf? (2, Informative)

SuperBanana (662181) | more than 7 years ago | (#16747309)

If they ran their shuttles on something like Debian stable it would be a rock solid platform and probably end up saving them lots of money. Or am I missing something here.

Yes, you are. Primarily the fact that Debian Stable isn't even Carrier Grade, and certainly not qualified for life support. Ie, "doesn't crash in the midst of re-entry."

Keep in mind that the shuttle computers are highly redundant (I believe there are three main computers, and three backups of each component?), monitor a HUGE number of sensors, control a large number of servos and other systems, do telemetry, etc.

Re:wtf? (4, Interesting)

tverbeek (457094) | more than 7 years ago | (#16747337)

Is there a reason these aren't built on standard parts and operating systems? If they ran their shuttles on something like Debian stable it would be a rock solid platform and probably end up saving them lots of money. Or am I missing something here.
Yeah, you're missing something. Such as the fact that the Shuttle was designed a quarter century ago, when Debian was so far from a stable release that Ian hadn't gotten the hange of long division yet, and still believed that Deb had cooties. "Standard parts" meant 8-bit CPUs with 64KB address spaces, and "standard operating systems" included CP/M, 4BSD, VMS, and an upstart known as PC-DOS. I can't really blame them for building something in-house instead.

Re:wtf? (4, Interesting)

Anonymous Coward | more than 7 years ago | (#16747579)

You neglect the fact that military/gov't programming languages at this time included HAL/S, Jovial, NELIAC, &c. (Yes I know that Jovial is still in use for the Navy's ITS 8/16bit muControllers). I've used XPL (the language that the HAL/S compiler was written in) & HAL/S; It was basically the predecessor to Ada/SPARK's 'provability' & 'stability'.
Here is a decent source of HAL/S examples:
http://www.hq.nasa.gov/office/pao/History/computer s/Appendix-II.html [nasa.gov]

Now, look at the procedure called 'read_accel', about 1/4 down the page.
Midway through, there is a ton of gunk. That's the HAL/S maths for you:
the program is allowed to use three lines to express mathematical code, to 'mimic' math
in code. Now, this is the '70s; it's of little wonder that they weren't worried about the
date switch so much as making sure that:
1) the compiler produced code that could be checked & double checked to be '100%' failure proof and at least be resilient to problems.
2) It had to deal with the beast of being machine independent & easily understandable to the PL/I & FORTRAN programmers of the day
3) It also had to make sure that tasks were scheduled properly & run when specific interrupts happened. This is the Norm for Ada/SPARK now, but HAL/S was pretty much the pioneer here within the Aerospace field.

Re:wtf? (0)

Anonymous Coward | more than 7 years ago | (#16747385)

It was built on "standard components" of the day. Similar architecture to IBM 360. The Altair wasn't even out then.

Why not Debian? Perhaps could have something to do with Linus not even being born when the shuttle was intially designed.

You young'uns need to learn a bit about history.

Re:wtf? (4, Insightful)

Schraegstrichpunkt (931443) | more than 7 years ago | (#16747433)

Is there a reason these aren't built on standard parts and operating systems?

Standard parts don't like being bombarded with radiation. Standard operating systems aren't fault-tolerant.

Re:wtf? (1)

Wanon (808109) | more than 7 years ago | (#16747525)

If they were using debian they could just update from the cvs and apply the diff and recompile ;)

I've attached it for them so they don't have to look up how to do a cvs update *cough*

0a1,2
> day = day % 365;
> year++;

Re:wtf? (4, Interesting)

E-Lad (1262) | more than 7 years ago | (#16747671)

You're indeed missing something here.

While I'm not thoroughly educated on this particular subject, I would say that it's a pretty good chance that the flight computers on the shuttles are based on technology that's at least 15 years old (all shuttles underwent a "glass cockpit" update in the mid-late 90s). You don't see NASA cutting a purchase order to cdwg.com when the newest AMD or Intel offering is announced and stuffing that into the shuttles. This stuff is designed, planned, coded for and integrated over a number of years and is very static. No changes. If there has to be changes, they're done under a quality control methods so strict that, yes, Duke Nukem 3D might see the light of day first.

And that's just the hardware part.

On the software side, I'd say you're probably looking at stuff written in any assortment of "classic" languages such as ADA, COBOL, or worse. Due to the nature of the metric f*k ton of sensors, mechanical servos, data inputs, and other such esoteric (and dated) hardware on the shuttles, the software must control, query, parse and monitor, the software is pretty darn married to the platform it runs on.

So, before blurting "D0odz, just instahl leenux n yr shuttlz (deeban stble rox wif glox!)" Give it some deeper thought. There's likely a darn good reason why things are they way they are (bugs not withstanding) when it comes to large flying contraptions that are designed to safely get 7 people 300 miles up, keep them there for a week (or two) and get them home. Sometimes simple things (to you and I) such as a year roll-over are outside the scope when it comes to designing systems to do what the shuttle does.

Re:wtf? (2, Insightful)

Xipher (868293) | more than 7 years ago | (#16747687)

On top of that, it's a realtime system, none of this get it done when I want to, its get it done by this dead line, or people DIE!

Re:wtf? (1, Insightful)

Anonymous Coward | more than 7 years ago | (#16747695)

i would much rather nasa use outdated yet 99% bug free tech than current buggy tech....there is little room for error in space travel.....as we all know (rip)

Re:wtf? (1)

gimplar (913105) | more than 7 years ago | (#16747923)

Yes. All the electronics on a flight system have to be qualified, from what I gather this process is rather involved and rigorous. The reason for all these qualifications is that a system must be predictable (that's why flight code is never..ever...ever written in an OOish type language i.e Java,C#). Also flight-systems must account for environmental hazards such as exteme temperatures, lack of atmosphere and radiation. Extreme temperatures is a pretty obvious one, the devices must be able to operate reliably in extreme cold or heat. A lack of atmosphere means that all heat generated on the system must be dissipated passively i.e through the chasis of the system. So you don't exactly want a Pentium 4 up there. Radiation is another big one, this is why (until recently) COTS (commerical off the shelf) chips can't be used. Because they haven't (or can't) be rad hardened. Radiation in space can cause upsets in the actual chips, as in a particle nails a transistor and causes a bit to flip. This can ultimately lead to the death of your chip, often times 'modern' flight systems deal with this by triplicating the system. Each chip comes to a result independently and then all three results are compared, then the best 2/3 results are considered correct and the third machine is reset back to a check-point. The millions and millions of dollars spent into designing space system usually goes into trying to get these things to be fault tolerant and efficient. In fact I think that future flight systems will start depending more and more on reconfigurable computing(FPGAs mainly, but emergent FPOAs may be an option) to achieve performance/power goals. And a lot of space systems do run a flavor of Linux, it's not Debian though.

Well.... (3, Insightful)

SuperBanana (662181) | more than 7 years ago | (#16747197)

...I guess it -is- rocket science.

*ducks and runs for cover*

Seriously though- they never "envisioned" a mission occuring over the end-of-year? Let me guess: a defense (space) contractor designed the systems.

Re:Well.... (1)

Detritus (11846) | more than 7 years ago | (#16747831)

Actually, no. Normally, the ranges are closed during the end of December for maintenance, and to let people take time off for the holidays. Think of it like a factory that has scheduled down-time.

Title mis-read (0)

Anonymous Coward | more than 7 years ago | (#16747201)

A computer dating error will affect the shuttle launch? I thought astronauts could get babes without resorting to computer dating...

y2k? (0)

Anonymous Coward | more than 7 years ago | (#16747223)

The real problem is that the shuttle isn't y2k compliant, and their "workaround" was to reset the year to 1999 before each launch.

Uhm...and? (2, Interesting)

QuantaStarFire (902219) | more than 7 years ago | (#16747233)

Pardon my ignorance, but is this really serious enough that it should actually cause a delay? I mean, if it's simply a matter of figuring out what the date is, I'm sure that the astronauts and engineers involved in the project know at LEAST basic mathematics, and can determine that if it's, say, Day 367 on the shuttle computer, then 367-365 = 2, AKA January 2nd, 2007.

I'd say the article missed something; the whole concept sounds far too ridiculous to stand on its own.

Re:Uhm...and? (1)

sexybomber (740588) | more than 7 years ago | (#16747253)

Yeah, it almost seems like an EXCUSE not to fly the shuttle. Are they getting paranoid about things going wrong?

Re:Uhm...and? (2, Informative)

Broken scope (973885) | more than 7 years ago | (#16747313)

Actually a lot of data is from that date. Navigation and other systems probably rely on the date being correct to give an accurate reading or reliable function.

Re:Uhm...and? (1)

QuantaStarFire (902219) | more than 7 years ago | (#16747359)

Okay, now THAT'S a valid reason; something TFA was missing. I'm still a bit skeptical though that a mere date could fubar things to such a degree, but I guess it's always the smallest problems that come to bite you in the ass (i.e. if(stringA = stringB) { /* stuff goes here */ })

Re:Uhm...and? (0)

Anonymous Coward | more than 7 years ago | (#16747815)

In which case day 366 of year 2006 should be equally valid as day 1 of year 2007. Seriously, navigation doesn't depend on our human representation of the calender.

Re:Uhm...and? (1, Informative)

Zordak (123132) | more than 7 years ago | (#16747451)

The article is sparse on details, but it sounds more like a problem where the date on the shuttles computer does not match the date on the ground system's computer. That can be a problem.

Re:Uhm...and? (3, Insightful)

plaxion (98397) | more than 7 years ago | (#16747521)

It probably has to do with the mismatch between systems, not a lack of the engineers' or astronauts ability to count on their piggies and toes. Their current configuration doesn't have a middleware layer that accounts for any possible differences. In other words, while the shuttle continues on thinking it's the 366th day, the ground control systems might get confused (e.g. "Hey, there's no such thing as a 366th day") and their programs may crash (no pun intended) as a result.

Oblig. (1)

Maow (620678) | more than 7 years ago | (#16747865)

[...] the whole concept sounds far too ridiculous to stand on its own.

Ahem.

You must be new around here.

Ba-da-bonk.

Huh? (1)

Salvance (1014001) | more than 7 years ago | (#16747237)

So we've been flying the space shuttle for almost 30 years and this was never viewed as a problem before? And we're trusting NASA to send astronauts to the moon and beyond over the next 20 years?

Re:Huh? (1)

Sage Gaspar (688563) | more than 7 years ago | (#16747921)

They had a system with some limitations that worked back in the 70's and was developed for lots and lots of money. They have a tried-and-true technology. The article says that their fleet is due to retire in 2010 and they were looking for a way to change this back in 2003, so my guess is probably that they're just waiting for the next generation of shuttle instead of retrofitting a system that already works within some bounds, which would cost both money and time. If they have to delay launches by a couple of months in the interim... well, that's not too steep of a price.

Re:Huh? (0, Flamebait)

mikelieman (35628) | more than 7 years ago | (#16747953)

"And we're trusting NASA to send astronauts to the moon and beyond over the next 20 years?"

No.

Only thing *I* trust NASA to do is waste money.

Bites me (2, Interesting)

William Robinson (875390) | more than 7 years ago | (#16747249)

The shuttle computers were never envisioned to fly through a year-end changeover

Sorry to sonud so skeptical....but am I the only one who is worried about capability of missiles (and other defence systems) to handle war through a year-end changeover?

Just goes to show (1)

gx5000 (863863) | more than 7 years ago | (#16747311)

Just goes to show how going for the lowest bid on a contract screws everything up.
That's barely ten lines of code no matter what language you want it in...
Sloppy, dreadful, and as I like to say, "You get what you pay for"...

(Does anyone remember the multi thousand dollar toilet seat for the US Navy ?)

In this case, a setback sending 1970's technology into space......
About time the new vehicle gets rolled out.
Maybe we can get Timex to code it in...

Cheers

Re:Just goes to show (1)

slimey_limey (655670) | more than 7 years ago | (#16747399)

That's barely ten lines of code no matter what language you want it in...

Unless, of course, you're using INTERCAL.

Re:Just goes to show (2, Insightful)

Alizarin Erythrosin (457981) | more than 7 years ago | (#16747785)

That's barely ten lines of code no matter what language you want it in...

Do you even remember why the Y2K thing happened? People saved space back in the day by using a 2 digit year. Hell, in the 1970's, people were using a one digit year to save even more memory and storage space. The Space Shuttle uses very old technology for its computer systems (read: 1970's level technology), and doesn't have much memory. That extra 10 lines of code could make it oversized.

Additionally, making a change to space (or even military) software requires a shitload of paperwork and testing. Its a wild guess, but it would probably take almost a year to get that "ten lines of code" into the Shuttle and cost more money than its worth to just not have the birds up in space at an end-of-year scenario.

And...? (1)

coolhelperguy (698466) | more than 7 years ago | (#16747343)

So far, there have been a bunch of comments on why this shouldn't have happened. Great, whatever. It is what it is.

So the question is, why does it matter? Day 1 or 366, it shouldn't matter, right? Unless they both didn't make it loop around and used functions heavily based on the date (not terribly likely), then what difference does it make? It's just December 31+1, so day-of-week, etc. should all remain correct.

It's not like NASA would just make a probably-multi-million-dollar-a-day wait because they felt like it. Obviously there's something up, so perhaps someone who knows could enlighten us?

Re:And...? (1)

swordfishBob (536640) | more than 7 years ago | (#16747501)

um, we're talking about orbits, intersections with other orbiting objects (and avoiding others). I think the date matters somehow, though it should be mostly in the planning.

Re:And...? (1)

mightyQuin (1021045) | more than 7 years ago | (#16747551)

There's gotta be SOMETHING running on a cron or schedule of some sort that depends on the date being correct.

Even if it's just an ageoff of some files or rotation of some logs.

btw - what's up with the Julian dates in space?

The name of the captain of the next flight is (0)

Anonymous Coward | more than 7 years ago | (#16747401)

Buck Rogers.

Of all the stupid things to get wrong... (1)

Finnegar (918643) | more than 7 years ago | (#16747437)

So, did they have to specially program the ground computers to act like all the rest on the planet, or did they leave out the few bytes this would have taken on the Shuttle to save some space?

Well, of course. (4, Funny)

T-Ranger (10520) | more than 7 years ago | (#16747467)

The shuttle runs on three modified IBM 360 systems. Were pushing 35, almost 40 year old systems here.

Do you know how many eligible 35 year old computer bachelors there are out there? Ill tell you: none. Of course the shuttle computers can't get a date.

Re:Well, of course. (1)

Btarlinian (922732) | more than 7 years ago | (#16747813)

Worst joke ever; nevertheless, I love it.

I'm surprised you aren't modded +5 funny or -1 (by the people who don't get it) yet.

basically . . . (1)

ElephanTS (624421) | more than 7 years ago | (#16747479)

I used to write this kind of glitch into my kludgy Commodore BASIC Vic20 programs when I was a kid. I never thought I was good enough to be a professional though. Seems like maybe there's a chance for me after this? I reckon the shuttle could run with BASIC if sensible line numbers were used. And GOSUBs for that professional touch.

Happy New Years! (2, Funny)

SpectreHiro (961765) | more than 7 years ago | (#16747511)

I read it quickly and thought it said, "The shuttle computers were never envisioned to fly through a year-end hangover".

I couldn't figure out for the life of me why they'd let mission critical crew drink bubbly in space... or why the computer would give a damn.

Computer date glitch (0)

Anonymous Coward | more than 7 years ago | (#16747517)

Well it sounds like they should have used a different computer dating service for that New Year's date. Maybe LavaLamp. Or eHarmony. That one costs serious money, but I hear the screening's a lot better. I mean sure you can get a date on Craigslist for free, but you get what you pay for, basically.

Hmmm (1)

gadgetman (4992) | more than 7 years ago | (#16747535)

The phrase "good enough for government work" comes to mind. This kind of crap really does (and should) irk every single tax-paying American. Shoddy design work like this should shame the contractor that billed the gov't for it.

I know it will not make the astronauts say much publicly about how they really feel to fly on the shuttle when this kind of news comes out, but I'm sure it makes the spouses and families of the astronauts have many sleepless nights.

Kind of makes me imagine what the space program would be if we combined common sense with the intelligence from those rocket scientists. Hmmmmm.

I'm enjoying a little schadenfreude... (4, Informative)

SchnauzerGuy (647948) | more than 7 years ago | (#16747541)

As a professional software developer, I have heard on countless occasions about how the Space Shuttle software development process [fastcompany.com] is so incredible, and how all other developers should try to live up their high standards.

Granted, the work they do is very impressive and the process is very exacting. But come on...they haven't been able to fix a simple year rollover event in 30 years?!?

From the Fast Company article:

Consider these stats : the last three versions of the program -- each 420,000 lines long-had just one error each. The last 11 versions of this software had a total of 17 errors.

I would say that requiring a reboot every year on December 31 is a pretty huge error. In this case, it is forcing NASA to launch earlier than they otherwise would wish. And this isn't the first time this type of problem has caused problems. The New Scientist has a similar article [newscientistspace.com] that goes into more detail:

This is not the first time that the shuttle programme has been faced with the year-end rollover problem. On a Hubble servicing mission in 1999, the year of the overblown Y2K computer scare, the shuttle landed on 27 December (see Fuel fault delays space repair). To make sure the shuttle got back on the ground before 31 December, mission managers decided to drop one of the four planned spacewalks.

Re:I'm enjoying a little schadenfreude... (1)

Nataku564 (668188) | more than 7 years ago | (#16747883)

Have you by chance considered that fixing it may cause more problems than it actually solves? Not all software behavior that seems strange is a bug. If its an understood part of the design, and you can work around it easily, then so be it. I would much rather fly on that, than knowing that the engineers had just added in shiny cool year-end date rolloff functionality that may or may not work, as opposed to the current software that has worked near flawlessly for decades. Especially with dates. They may seem simple on the outside, but after having worked in the financial industry for 5 years, I cant tell you how fscked up our calendar system is.

If it ain't broke (3, Interesting)

GreggBz (777373) | more than 7 years ago | (#16747571)

So, they made the software so it does not kill anyone. Who needs fancy features like precise yearly timing?

Seriously, though, it's worked fine. The software has not killed anyone. They can either fix it and modify a very critical system on an enormously complex vehicle, or they can move the launch date around a few days, which they seem to do for every launch anyway. B is probably safer and more predictable.

Problem seems obvious (2, Funny)

Jozer99 (693146) | more than 7 years ago | (#16747633)

The problem seems obvious. If the shuttle computer is allowed to think it is the 366th day of the year, it will obviously turn evil and try to destroy the earth using the vast orbiting nuclear arsenal, while we sit helpless on the surface. We can't allow this to happen.

Re:Problem seems obvious (1)

QuantaStarFire (902219) | more than 7 years ago | (#16747801)

"On December 32nd, 2006, Skynet became aware and launched a space-based retaliatory nuclear strike against its human enemies."

There's a pointy haired boss that needs sacking (0)

postbigbang (761081) | more than 7 years ago | (#16747685)

After all NASA has done to put satellites into the drink, endanger astronauts, and soak money like LA uses water, you'd think there'd be no embarrassing bugs like this one. Someone needs to be looking for a job flipping burgers.

I can buy no excuse for something as inane as this. No one takes responsibility any more. There's a project manager that needs to fall on his sword. Or get pushed.

Date/Time Formats (4, Informative)

Detritus (11846) | more than 7 years ago | (#16747731)

The problem is that NASA, and other space agencies, standardized on a date/time format composed of day-of-year (1..366) and time-of-day (UTC). This goes back to the 1960s. In ASCII, the clock looks like "310 04:35.27.642". This date/time format is embedded in a huge amount of hardware, software and standards documents. It's also used for things like countdown clocks and MET (mission elapsed time) clocks.

The end-of-year rollover depends on the leap year and leap second (if any), and has traditionally been a source of problems.

Could it be... dates are hard? (3, Insightful)

tlhIngan (30335) | more than 7 years ago | (#16747755)

Could it simply be that the date is a hard concept? You've got months with uneven number of days in them, including one month that can have an extra day added to it based on a somewhat complex concept (every 4 years, except if it's divisible by 100, UNLESS that year also happens to be divisible by 400). Calculating how many days there are between now and some future date, without using magic numbers? Heck, even software in the 90's couldn't get it right that there was a Feb 29, 2000.

Every date math equation I've seen has all sorts of wierd magic numbers in them where it isn't clear how those numbers were obtained. This may work just fine in day to day computations, but oddball bugs in date calculations can lead to some very wierd errors. Look at the C library sometime for the date functions. It's quite impressive.

Perhaps when the shuttles were designed, the inability to schedule across the new year was acceptable to avoid introducing odd bugs in the program to keep the software provably correct. Ground systems, which can be repaired in the middle of a mission easily, can be a little less bug-free, since a miscalculation won't cause the Earth to suddenly veer off course.

Re:Could it be... dates are hard? (1)

Shados (741919) | more than 7 years ago | (#16747841)

Indeed. The date system is all made to periodicaly fix itself to compensate for little details, like the fact that there isn't an integer amount of time the earth spin on itself in the time it takes it to spin around the sun, and a bazillion other details. Its just not worth it. Make 10 freaking month, 3 weeks of 10 days (or something), and thats one year. 1 day has 10 hours of 100 minutes each with 100 seconds. Use round numbers. So for now winter will be on month 5, in a few years winter will be on month 9. Who cares. We already have to use calendars or take out our calculators to figure out certain holidays, daylight saving time's day is different each year... there isn't any consistancy to begin with. Lets just make things simpler and be done with it. The only thing that would get tricky is store open hours and the start and end of a work day, since it kind of has to match with the sun, and thats arbitrary (compared to a fixed system, that is). Anyone has a suggestion on that one?

a "year" in Space ? (1)

copdk4 (712016) | more than 7 years ago | (#16747849)

I think it would take rocket science to figure out the notion of year, say for example, on moon or mars - so I guess there is reason for 1st Jan being considered as the 366th day.

Re:a "year" in Space ? (0)

Anonymous Coward | more than 7 years ago | (#16747937)

But then, what is a "day"?

Hold up, everybody (4, Insightful)

Alizarin Erythrosin (457981) | more than 7 years ago | (#16747891)

I work with military navigation software, and that is sorta remotely applicable to this. Here's my thoughts:

You people with your "WTF NASA SUXORS THIS IS EASY FIX!!!11!!1!one!!" need to stop and think for a second. This is a space application that carries HUMAN BEINGS! Think about how hard it will be to get this "easy fix" qualified, proven, documented, etc. Its not an easy task. A formal qualification test on the systems I work on (military land- and air-, but not space-based navigation software) can take months, and require all sorts of tests and documentation. Anything that isn't formally tested (i.e. run in a van, on a plane, etc) must be shown to not fail in any way; all exceptions handled, no bad data can cause an undesireable state, etc. I would hate to see the type of scrutiny that the Shuttle software goes through (although I could probably call somebody in our Space division across the street and find out).

Second, I don't know exact specifics, but based on the information provided, I think this "glitch" will have to do with the data/time difference between ground stations and the Shuttle computers. Things like message time stamping between the Earth and the Shuttle, etc, will be wrong, and things could be garbled or just dropped all together. The navigation systems themselves should not be terribly impacted since the date will just roll to the next day. Inertial instrument samples will continue to flow in and be correctly time stamped, be it the 366th or 400th or 500th day.

Re:Hold up, everybody (0)

Anonymous Coward | more than 7 years ago | (#16747957)

Yeah,but I live next to the grandfather of the guy that washes the car of the boyfriend of the guy that went to space camp. So you can tell I know what I'm talking about. Plus. I once road in a space ship in a kmart parking lot for only a quarter. Based on my information, I'd say their flux capacitor runs on alcohol, which runs low on new years. It should be a simple fix of giving pinball parts to the lybians in exchange for some plutonium to substitute for the lack of alcohol.

Deja Vu (0)

Anonymous Coward | more than 7 years ago | (#16747917)

So, NASA is partying like it's 1999 huh?

CMMI Level 5 (1)

jvance (416133) | more than 7 years ago | (#16747965)

CMMI Level 5 Waterfall at its finest. Every jot and tittle accounted for, except for the things that were missed.

Dates? What for? (0)

ozbird (127571) | more than 7 years ago | (#16747971)

Why does the onboard computer need to know the date? To send greeting cards on the astronauts' birthdays? Does a date even make sense when you orbit the Earth several times each day?
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