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Posted by: dot.dk Nov 19 2005, 06:18 AM

One martian year coming up in a few hours!

Nov. 19, 12:23:40 PM UTC if my math is correct

It's hard to describe what a fantastic achivement this is. So I'll just say:



Let's keep on roving!


_||_____O___|__
///////////////////

Posted by: Nix Nov 19 2005, 06:59 AM

Amazing..Thank you Rover-teams!!

Nico

Posted by: deglr6328 Nov 19 2005, 08:06 AM

Stunning. Did anyone, anywhere ever actually predict this? With Oppy at 4 miles and Spirit nearing 3.5 and the power output on Oppy back up to 720W/Hr again it really looks like the only thing that can kill them is a massive dust storm or a sudden component failure! How are they doing with respect to all the other mechanical aches and pains they've both had over the sols so far (sticky wheels, glitchy MI operation)? Aside from Oppy's mysterious occasional reboot, have they all just worked themselves out?

Posted by: MichaelT Nov 19 2005, 08:16 AM

That's a nice birthsol card, dot.dk

My thanks and best wishes, too, go to Spirit, Oppy and the rover team!

Michael

Posted by: Bill Harris Nov 19 2005, 09:24 AM

Wonderful birthsol card, dot.dk .

Happy first birthsol, Spirit and Opportunity. May you have many more productive Sols!

--Bill



PS- great sigline, too.

Posted by: jvandriel Nov 19 2005, 09:26 AM

For more information about Mars and scientific publications look at the following website:


http://marsjournal.org/



jvandriel

Posted by: general Nov 19 2005, 10:06 AM

Happy birthsol (or should that be "mars-anniversary" ), Spirit.
And many happy returns!

Posted by: helvick Nov 19 2005, 10:16 AM

I'm not sure if I totally agree dot.dk's calculation of the exact timing of the birthsol but the Birthday card is so damn fine that I need to beg his forgiveness for being a nit pick.

Sol 1 started on the Midnight before Spirit's landing.
There are 668.5921 Sols in a Martian tropical year.
It can be argued that the Marsiversary Sol should therefore start on Sol 669. *
However the the exact timing of the passing of 1 Martian year from the start of Sol 1 takes place at 14.21 local Martian time on Spirit Sol 669 due the 0.5921 fractional part.
Spirit landed at 14:26 local time (LST-A) on Sol-1 so the timing of 1 Martian year after that actually occurs at 4:47 on Sol 670.

* Using Earth Dates and Days.
Landing: January 4 2004 at 04:36 UTC.
Martian tropical year (in days) 686.9725.
Add the two and you get 03:56 on November 21 2005 for the actual event.

Posted by: ToSeek Nov 19 2005, 04:42 PM

It's a stunning accomplishment. I was scoffing a while back at someone who enthusiastically believed that at least one of the rovers would make it to Sol 1000, but it seems more likely all the time.

Posted by: ElkGroveDan Nov 19 2005, 05:18 PM

Great calculations. Now can you tell us how many angels can dance on the head of a pin?

Posted by: helvick Nov 19 2005, 06:45 PM

Thanks Dan. I just knew I'd get slapped for being a pedant.

The answer to your very topical question depends on what sort of dance. It may depend on other parameters too, I'll have to do some research. Questions that spring to mind are: What sort of Angels? Do I have to consider Archangels, Metatrons and Fallen Angels? What sort of pin? Is the head of a pin the blunt or the sharp end? What about ambient temperature since http://www.lhup.edu/~dsimanek/hell.htm?

Posted by: DEChengst Nov 19 2005, 10:58 PM

I just send a short email to Steve Squyres on behalf of all the #space members on irc.freenode.net. I included dot.dk's picture as a birthsol card:

Posted by: RNeuhaus Nov 21 2005, 02:11 AM

I am very happy to celebrate one birthsol of MER-A and soon another party for MER-B.

The mission of MER is incredible for me since it has brought lots of science, discoveries, learning, surprises, speculations, discusions, and funy time about bets of the probable route plan, arriving dates, probably next breakdowns. We had guess correctly to fews (East ridge, Utreya) and failed some guess (route to south to Erebus, sooner breakdown of Oppy).

I think that the MER's mission is the first type of sharing information (fast and *complete* information) that has created a new big international member with diversity of talents and perspectives that make up interesting debates. Hope that MER team has listed us and picked us some good contributions.

Thanks to dot.tk for a nice card.

Rodolfo

Posted by: alan Nov 21 2005, 03:58 AM

Happy Marsiversary Spirit

Posted by: jamescanvin Nov 21 2005, 04:29 AM

What an amazing achevement! (to add to all the other amazing achevements ) Who would have thought it, I remember being amazed when the number 250 was mentioned at around sol 90! I would surely have laughed at anybody silly enough to talk about ONE WHOLE MARTIAN YEAR!

Bring on Oppys marsiversary in three weeks, then were off toward the heady realms of Sol 1000, I think I feel feint

Amazing days (sols),

James

Posted by: akuo Nov 21 2005, 08:42 AM

Again congratulations to Spirit and the team for surviving a whole Martian year on the surface.

This is an important achievement since now a rover has weathered the conditions on Mars for a whole orbit. Earth years come and go, but those do not affect Spirit as a Martian year does. It is truly a Martian in a Martian environment.

I don't think a second Martian year is viable. There are many factors, of course the electronics might still fail any day and there might be a long period of no dust cleaning. Dust storms don't seem a threat anymore, since the season is about over (well, except for the next summer. Maybe the big one will hit then!). The batteries are li-ion, which are limited by age, not so much by the number of charges (many notebook users have experiences on this when an unused "backup" battery doesn't work after being left unused). The batteries have been rated at 5 years, which is from the time of manufacture. That date will be upon us fairly soon, and it might bring a surprisingly quick battery death.

I have been surprised how well the MERs have been supported by NASA with its resources. There was talk that the solly data stream would be reduced soon after the primary mission. Spirit and Oppy are still sending similar amount of images and other measurements as they did at the beginning of the mission. Maybe this is because of effient use of Mars Odyssey, but that still takes DSN time. NASA might extend the mission after the sol 1000 date, but maybe with even further reduced staffing and other resources. As Steve said, Oppy might roll to Victoria with only handful of graduate students onboard.

Posted by: jvandriel Nov 21 2005, 09:16 AM

It seems that NASA ( JPL ) has learned from some of the members of this forum by putting Spirit on 3 images. ( great images )

Just published on their website.

They call it Special-Effects.

jvandriel

Posted by: SigurRosFan Nov 21 2005, 12:41 PM

Here is the link:

http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20051121a.html - Special-Effects Spirit in "Columbia Hills"

My favorite is Spirit near Larrys Lookout.

Posted by: Bill Harris Nov 21 2005, 01:16 PM

>They call it Special-Effects.

...special effects on a false-color image.

They do read this site, and are adaptable.

--Bill

Posted by: odave Nov 21 2005, 02:58 PM

Unless I missed something over the weekend, it looks like all the official sites ignored Sprit's birthsol. I would expect some kind of mention on the MER page, but I haven't seen anthing. Do they think the general public wouldn't understand what a Mars year is?

Poor Spirit

Don't worry sweetie, we at UMSF remembered you on your special sol...

Posted by: Gonzz Nov 21 2005, 03:03 PM

Hi SigurRosFan, slightly OT but yesterday we had here in Lisbon another great concert by Sigur Ros, man, it's the closest you can get to a beautiful alien landscape!

Posted by: Reckless Nov 21 2005, 03:54 PM

The Special effects are all of Spirit and look birthday cardish, so perhap it's a silent happy birthsol and maybe we'll see the same thing for oppy in twenty days or so.

Reckless

Posted by: general Nov 21 2005, 05:07 PM

Official recognition
http://marsrovers.jpl.nasa.gov/spotlight/spirit/20051121.html

Posted by: general Nov 21 2005, 05:15 PM

I like this:

"While no one can predict how long Spirit will last, the rover's stamina throughout the long martian year encourages hope. The science team is busy even now plotting new destinations to strive toward. If the "Columbia Hills" were once a distant dream, new far-off horizons beckon just as much. Getting there will stretch the rover's capabilities as much as the imagination. Team member Jim Rice calls one such distant target, a rough and rugged terrain to the south, "the Promised Land."

http://marsrovers.jpl.nasa.gov/spotlight/spirit/images/20051121_promisedland_br.jpg

Posted by: odave Nov 21 2005, 05:17 PM

Ah, I guess they were using Helvick's math

Posted by: helvick Nov 21 2005, 06:43 PM

It's the engineer in me - always pessimistic.

Posted by: Tman Nov 21 2005, 06:51 PM

Nico, I'm romantic and love this sunset pose of Spirit. Additional it was even dangerous for Spirit to drive over Methuselah to catch this pose

Hey, they even tried to retouch the track from Spirit in the second image - indeed looks more realistic.

Happy Birthday Spirit!!!

Posted by: odave Nov 21 2005, 06:54 PM

...and after that, I wanna drive that sucker straight up Ma'adim Vallis

Posted by: Burmese Nov 21 2005, 08:57 PM

And from Cornell:

http://www.cornellsun.com/vnews/display.v/ART/2005/11/21/4381771b9eb25

Posted by: jamescanvin Nov 21 2005, 09:55 PM

Gosh, I'm glad now that I stopped using "the Promised Land." as the caption for my inner basin pan after the first iteration, that would have confused things!

Posted by: hansvi Nov 22 2005, 12:28 AM

What a mission! And it seems they might last another martian year! If they can operate the rovers until the batteries are as dead as the one in my cellphone, they will have squeezed every last drop of science out of them I guess. (Even then, the rovers could still carry on; I have read the batteries can be disconnected, running the rover solely on solar power).

Looking forward, I wonder what the next milestone will be. Has any of the rovers left the landing ellipse yet?

Keep it coming!

Posted by: RNeuhaus Nov 22 2005, 12:35 AM

Next Milestones:

Spirit: Probably, first traverse along one of terraces in order to visit Utreya *Abyyse* , zone with black or dark sand and later to Home Plate, in South of Hill Columbia.

Oppy, Visit the rim of Erebus until the Mogollon's rim at the souther most of Erebus very old and almost buried crater and then left here by going toward to next biggest crater and also deeper that Oppy has ever visited. It must probably around 2 km south and west of Erebus.

Only one, Oppy is approaching the limit of landing ellipse.

Rodolfo

Posted by: dilo Nov 22 2005, 01:35 AM

I already posted image in another thread, but now I think this is the best place for Full-Res version.
This is my tribute to MER team, deepest gratitude to you!

Posted by: jamescanvin Nov 22 2005, 03:17 AM

Nice one dilo, nice to have a picture of Spirit on her birthsol.

Your "mission primary target" line on the graph confused me at first, I was thinking "surely there was no target of ~70m/day" that was just me being tired and stupid! But it made me think that another way of marking that graph would be a differently shaded box between 0-90 sols and 0 - 600m showing just how far outside the original mission requirment envelope we now are. It seems a shame on a graph with clumulate distance traveled not to show that we're not far off 10 times the mission requirement!

Nice work, cheers,

James

Posted by: dilo Nov 22 2005, 07:11 AM

Good point, james!
I updated the plot, up to now Spirit lasted 7.5 times the primary mission life and covered a distance 9 times longer
I already highlighted in this http://www.uai.it/index.php?tipo=A&id=1098.

Posted by: jamescanvin Nov 22 2005, 09:47 AM

Looks good Dilo, exactly what I had in mind - such a small box in the corner!

May it get much smaller before were done.

Posted by: Nirgal Nov 23 2005, 11:58 PM

It's a little late, but here is my birthsol present for Spirit:

http://mitglied.lycos.de/user73289/misc/spirit_f671_col.jpg

Posted by: SigurRosFan Nov 27 2005, 05:41 PM

Was this your first time to see Sigur Ros in concert?

Posted by: Gonzz Nov 27 2005, 06:30 PM

Yes, it was the third time they played here in Lisbon though. I had only heard about them by the time they came for the second one (about when they released the () album), but all tickets were sold out, friends of mine who did see it were absolutely amazed.
So I had my hopes up for this third time around and it was quite incredible. I love their music, and played live it seems to go even higher, wonderful concert.

And there's that slight alien soundscape, you're not totally earthbound when listening to them

Posted by: ljk4-1 Nov 28 2005, 03:43 PM

Spirit completes her first Martian trip around the sun

http://www.news.cornell.edu/stories/Nov05/Spirit.Martian.year.lg.html

Nov. 23, 2005

By Lauren Gold
lg34@cornell.edu

The intrepid Mars rover Spirit was excused from attending the Nov. 18 party in her honor. She was busy climbing down from the summit of Columbia Hills and heading toward a new target called Home Plate, while wrapping up her first trip around the sun since landing on Mars in January 2004.

But she was present in -- well, spirit.

The Cornell contingent of NASA's Mars Exploration Rover mission saluted the rover with a gathering at the Space Sciences Building -- two days before the official moment (7:37 p.m. Sunday, Nov. 20) occurred.

"To me this is one of the most significant milestones in this project," said Steve Squyres, the mission's principal investigator and Cornell's Goldwin Smith Professor of Astronomy. "We have gotten to experience Mars in all the seasons of the year. We've seen all of its moods."

Posted by: elakdawalla Nov 28 2005, 04:43 PM

Planetary Radio, Monday, November 28, 2005:
http://planetary.org/radio/show/00000128/

We celebrate a Martian year of exploration by the Mars Exploration Rovers with Jim Bell, Cornell planetary scientist, member of the MER science team, and new Planetary Society board member.

Posted by: Sunspot Nov 28 2005, 04:48 PM

Ask him whats going on with Opportunity

Posted by: exobioquest Nov 29 2005, 07:23 PM

Is there an article somewhere on the forum dedicated to discussing how long MER will last?

Who many cleaning events have there been? Is there a chart of solar cell output levels for either rover? Will solar cell output ever become a problem at this rate?

How long will the batteries last? How many cycles have they taken and when is the end of the warranty date for them?

What aliments does each rover have as of now?

Posted by: dilo Nov 29 2005, 07:56 PM

Try to digit "batteries" in the Forum search engine.
I found, in particular, following threads that should contains answers to most your questions:
http://www.unmannedspaceflight.com/index.php?showtopic=1363&view=findpost&p=19462
http://www.unmannedspaceflight.com/index.php?showtopic=1204&view=findpost&p=15561
http://www.unmannedspaceflight.com/index.php?showtopic=1551&view=findpost&p=23564

Posted by: odave Nov 29 2005, 08:12 PM

I'd check out the interview Doug did with Steve Squyres back in September for some insights on this. http://www.unmannedspaceflight.com/index.php?showtopic=1367and http://www.unmannedspaceflight.com/index.php?showtopic=1683 are available.

But it may be helpful to summarize the current ailments in one spot. The ones I know of off the top of my head are:

* Spirit: RAT teeth are shot.
* Spirit: One of the drive wheels was sticky, but has since fixed itself
* Oppy: Right-front steering actuator is stuck
* Oppy: A heater is stuck on
* Oppy: Mini TES is flaky - stopped working, then started working again
* Oppy: MI comm sometimes returns errors - EDD may have cable fraying
* Both: Mossbauer source is depleted to ~25% of landing, integrations take longer

And there's the current anomaly with Oppy's MI images, but that's not confirmed as an ailment.

Please correct/add to the above.

EDIT: Added Mossbauer source depletion

Posted by: helvick Nov 29 2005, 08:37 PM

I don't think there's been a dedicated thread but I've dug into this quite extensively, some might say obsessively.
Anyway I have a bunch of excel spreadsheets that I put together earlier this year that estimate what the power should be but I've only been able to find ~25 published data points for Opportunity and 14 for Spirit so it is very hard to actually chart the performance of the panels. One of them is posted here somewhere but the data is very much out of date and it is based on a bunch of assumed data. I also have a bunch of Perl scripts that I hacked together more recently to create a pretty decent Insolation model that in the end don't significantly improve on the Excel spreadsheets ability to predict future power generation levels.

The team have reported about a half dozen cleaning events per rover. Some were relatively small (Opportunity is believed to have had a couple of 5% events while in endurance) but both rovers have had 2 or three major cleanings that improved power generating capability by 20% or more, all of those happened in the last 12 (earth) months.

One of the published papers by the team stated that the power loss due to dust deposition followed the expected pattern for the first 100 or so sols (ie 0.18% reduction per sol) however only two actual data points were ever published for those periods (Opportunity Sols 80 @ 610 watt hours and 93 @ 593 Watt hours). As far as I can make out power continued to degrade pretty much exactly as per the predicted model until Sol 204 for Spirit and Sol 198 for Opportnity. Spirit got into some complex geography at that point so orientation caused power problems for a while but Opportunity was delving into Endurance and benefiting from a favourable orientation that boosted power by about 25%.

I'm reasonably sure now that that dust deposition rate decreased significantly once the atmosphere cleared up about halfway through SH Autumn (at around Spirit Sol 130 or so), then we had the major cleaning events about halfway through winter (December 04 for Spirit and Jan 05 for Opportunity). Dust deposition seems to have remained low until a few months into spring (around may of this year) as the amount of dust in the atmosphere rose again. It is reasonable to assume that the rovers are once again subject to approximately 0.18% reduction in power per sol and that degradation will continue until around Sol 780-800 (Mid April 2007).

Recent published power numbers (Opportunity 720 Watt hours on sol 628, Spirit 650 at around the same time) lead me to believe that the current worst case scenario (no more cleaning events) would have the rovers hovering around 300 Watt hours per sol generating capacity around Spirit sol 870, June 14 2006. That's pretty low but it's survivable and should still allow some activity particularly if the drivers\planners are creative about finding North facing slopes to park on.

My best guess now is that since the major threat of dust storms has pretty much passed for this martian year there is no reason to think that either of the rovers cannot generate enough power to survive through the winter. The power situation improves fairly rapidly after that provided my guesses about the reduction in dust deposition rates are correct.

I was of the opinion that the batteries were likely to fail as we closed on 1000 sols but someone else (I forget who) posted here that they should be good for 2000 or more charge cycles (I think). If that's true then power is not going to be a death threat. I think they go through a charge cycle per Sol more or less but can't be sure of that - I do know that they got a surprise recently when Oppy failed to charge one of it's batteries which led me to assume that bringing the batteries up to a full charge was a standard daily procedure.

The MiniTES instruments seem to be the most likely components to break first simply because they are temperature sensitive and they are no longer being heated at night. Oppy's has already caused a bunch of problems and it should have frozen to death in the middle of winter when they adopted deep sleep.

Other than that Spirit's RAT is burned out, or virtually burned out. We've had front wheel problems on both rovers but neither seems hugely problematic. Oppy has a stuck heater but deep sleep seems to be enough to cope with that. They may be problems with Oppy's IDD at the moment, we don't know.

I'm more optimistic about their long term survivability as rovers now than I have been in well over a year but then again something nasty could happen at any time.

Posted by: exobioquest Nov 29 2005, 09:42 PM

Thank you all for the data

So from the charts and all if they are going to die this martian year its going to be in mid winter (sol ~900+/-50) either (unlikely) solarpower input to low, or thermal cycling of the electronics causing a lethal "stroke" which should be at its worst in mid winter because of the low temps and low power causing the need for things like deep sleep. If they survive that they are set for another martian year! Though a electronics break down could happen anytime and chances increase with every sol I'm guessing winter is when the rate of chance increase goes up fastest.

So here is my prediction, but don't call be psychic or a warlock if I’m right:

Opportunity will wake up some cold winter day and as the electronics warm up something will snap: as is the semi-frequent(?) reboots might be a sign of micro-cracks forming in the soldering causing echoes and noise in the signals and increasing the chance of bad bits. After the snap opportunity might either be stuck in a set of infinite reboots or might not wake up at all (the BIG sleep). Of course we on earth won’t know what happened because of a lack of telemetry, even worse Opportunity might be able to weakly reply but not be commendable (like road-kill that is still alive and trying to crawl away, traumatizing sad to watch!), once Opportunity is finally put out of its misery it will be only a matter of time until it happens to Spirit, maybe the winter after or any random day after 1000sols.

Posted by: helvick Nov 29 2005, 10:23 PM

That's it.
Overall the Solar Panels have performed very well and the pre flight models of their behavior seem to have been totally validated. These rovers have been lucky though and we would do well not to forget that. The 90 day mission had sensible safety margins but they have survived this far by the slimmest of margins, well Spirit has at any rate.

Posted by: ljk4-1 Nov 30 2005, 02:30 PM

Guy Webster (818) 354-6278/5011

Jet Propulsion Laboratory, Pasadena, Calif.

George Deutsch/Erica Hupp (202) 358-1324/1237

NASA Headquarters, Washington

News Release: 2005-167 November 29, 2005

NASA Rover Helps Reveal Possible Secrets of Martian Life

Life may have had a tough time getting started in the ancient environment that left its mark in the Martian rock layers examined by NASA's Opportunity rover. The most thorough analysis yet of the rover's discoveries reveals the challenges life may have faced in the harsh Martian environment.

"This is the most significant set of papers our team has published," said Dr. Steve Squyres of Cornell University, Ithaca, N.Y. He is principal investigator for the science instruments on Opportunity and its twin Mars Exploration Rover, Spirit. The lengthy reports reflect more thorough analysis of Opportunity's findings than earlier papers.

Scientists have been able to deduce that conditions in the Meridiani Planum region of Mars were strongly acidic, oxidizing, and sometimes wet. Those conditions probably posed stiff challenges to the potential origin of Martian life.

Based on Opportunity's data, nine papers by 60 researchers in volume 240, issue 1 of the journal Earth and Planetary Science Letters discuss what this part of the Martian Meridiani Planum region was like eons ago. The papers present comparisons to some harsh habitats on Earth and examine the ramifications for possible life on Mars.

Dr. Andrew Knoll of Harvard University, Cambridge, Mass., a co-author of the paper, said, "Life that had evolved in other places or earlier times on Mars, if any did, might adapt to Meridiani conditions, but the kind of chemical reactions we think were important to giving rise to life on Earth simply could not have happened at Meridiani."

Scientists analyzed data about stacked sedimentary rock layers 23 feet thick, exposed inside "Endurance Crater." They identified three divisions within the stack. The lowest, oldest portion had the signature of dry sand dunes; the middle portion had windblown sheets of sand. Particles in those two layers were produced in part by previous evaporation of liquid water. The upper portion, with some layers deposited by flowing water, corresponded to layers Opportunity found earlier inside a smaller crater near its landing site.

Materials in all three divisions were wet both before and after the layers were deposited by either wind or water. Researchers described chemical evidence that the sand grains deposited in the layers had been altered by water before the layers formed. Scientists analyzed how acidic water moving through the layers after they were in place caused changes such as the formation of hematite-rich spherules within the rocks.

Experimental and theoretical testing reinforces the interpretation of changes caused by acidic water interacting with the rock layers. "We made simulated Mars rocks in our laboratory, then infused acidic fluids through them," said researcher Nicholas Tosca from the State University of New York, Stony Brook. "Our theoretical model shows the minerals predicted to form when those fluids evaporate bear a remarkable similarity to the minerals identified in the Meridiani outcrop."

The stack of layers in Endurance Crater resulted from a changeable environment perhaps 3.5 to 4 billion years ago. The area may have looked like salt flats occasionally holding water, surrounded by dunes. The White Sands region in New Mexico bears a similar physical resemblance. For the chemistry and mineralogy of the environment, an acidic river basin named Rio Tinto, in Spain, provides useful similarities, said Dr. David Fernandez-Remolar of Spain's Centro de Astrobiologia and co-authors.

Many types of microbes live in the Rio Tinto environment, one of the reasons for concluding that ancient Meridiani could have been habitable. However, the organisms at Rio Tinto are descended from populations that live in less acidic and stressful habitats. If Meridiani had any life, it might have had to originate in a different habitat.

"You need to be very careful when you are talking about the prospect for life on Mars," Knoll said. "We've looked at only a very small parcel of Martian real estate. The geological record Opportunity has examined comes from a relatively short period out of Mars' long history."

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Mars Exploration Rover project. Images and information about the rovers and their discoveries are available at http://www.nasa.gov/vision/universe/solarsystem/mer_main.html .

Posted by: alan Dec 10 2005, 09:30 PM

So Helvick, when does it become official for Oppy?

Posted by: djf Dec 11 2005, 06:02 PM

Well, using 686.9725 days and a 05:05UTC landing time it seems to be 12 Dec 04:25 UTC...

% setenv TZ UTC

% date +%s -d "Jan 25 05:05 UTC 2004"
1075007100

% bc
686.9725*86400
59354424
1075007100+59354424
1134361524

% convdate -c 1134361524
Mon Dec 12 04:25:24 2005

Posted by: dilo Dec 11 2005, 06:35 PM

Just made an Opportunity dedicated http://www.unmannedspaceflight.com/index.php?showtopic=1824&view=findpost&p=30823.