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Exceptional Seeing At Dome C in Antarctica
Michael Ashley writes "A paper published in Nature
today reports on the exceptional
astronomical seeing conditions at Dome C (Coral link)
in Antarctica. Obtaining the data posed some significant technological
challenges, given that Dome C is uninhabited over winter. The
experiment was controlled by a PC/104
computer system that had to survive temperatures down to -85C, and
supervise the generation of its own electricity using a jet-fuel
powered stirling engine. The computer, running Linux, communicated with
the outside world using an Iridium
phone. The results are also covered in New
Scientist, and the Sydney
Morning Herald. Disclaimer: I'm a co-author."
Looks like making the ozone hole actually accomplished something.
The experiment was controlled by a PC/104 computer system that had to survive temperatures down to -85C...
;-)
Wait a sec! =-P Computing equipment *loves* cold, as long as you don't have to worry about condensation. =-P In other words, it's not hard to design a system that can survive -85C. Just do a google search for Liquid nitrogen cooling. Yay for overclocking fiends who make it so you don't even need to mention computing hardware.
btw, there's a tom's hardware link on the results page. Check it out. There's a pic of a CPU mount covered in frost. That *can't* be good! =-P
Look at this photo. It is the author's Kyocera mobile phone with a web page showing the temperatures, memory usage and free disk space. Says battery temperature is -34.5 (is that C or F?)
2bits.com, Inc: Drupal, WordPress, and LAMP performance tuning.
What is "seeing"?
"Seeing" is a term that astronomers use to quantify the turbulence in the atmosphere and how it affects observations from the ground. The stars appear to twinkle because of the effect of this turbulence. In conditions of bad seeing, the stars appear to twinkle vigorously, and the images that you take with your telescope are blurry. In conditions of good seeing, the stars appear more stable, and you can take very sharp images.
You'd think they'd have a cooler word for that...
I would have to say Linux was the ideal choice in this case. Penguins are polar creatures. you know. I wonder how the Microsoft Rainbow-bee-man would've fared under such conditions.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
Hell, all that they had to do was stick a new Geforce and an Athlon in there and she'd be warm as toast ;)
You create your own reality - Leave mine to me.
The link that the submitter provided to himself doesn't work. The correct link is: Michael Ashley
I work with Diamond Systems PC/104 computers everyday. These systems are robust and the specifications for operating environments are crucial to applications such as these. Their ability to operate in extreme conditions, temperature, vibration, make them fit for such roles.
We've used PC/104 computers (running QNX 4.25) for everythign from Remote power stations, Fuel cells, even UAV's.
Harder.. Better.. Faster.. Stronger
Base camp: So how's it going there?
Dome C: Weh, Biwwy daywed me to stiwck my tung to the waw. Oh, and we'we outta beew....
"All great things are simple & expressed in a single word: freedom, justice, honor, duty, mercy, hope." --Churchill
A PC/104 is just a form factor. And provides standards for things such as environmental operating parameters.
CPU boards usually have an intel clone processor MACH86 or VIA Athena.
So they can run any OS your desktop can.
Harder.. Better.. Faster.. Stronger
Just stick .nyud.net:8090 on the end of your domain name (before the /) and it'll grab the content and cache it -- any future queries will return their cache instead of downloading from the original page. The coral links also work like your web browser and update the content when it is out of date.
One experiment, ICECAM, relied entirely on a 5 kg pack of lithium thionyl chloride batteries. The batteries had to provide power for a year, so minimized the power consumption of the computer. The experiment only needed to take data every two hours, so we built a CMOS oscillator to power-up the computer for 30 seconds every two hours. We used MS-DOS 6.22 for the PC/104 computer since it boots quickly and was able to average 10 frames from the CCD camera and store them to CompactFlash disk.
www.bannination.com Two things float to the top he
so, how far is the secret nazi base from Dome C?
Stay away from the Norwegian camp....they dug up something in the ice and we've lost contact with them....
Last we heard, one of their sled dogs were running this way with a helecopter following it....
"Leo Fender was in a 'state of grace' when he designed the Stratocaster." -- Paul Reed Smith
So they went bankrupt, and no one would buy the system. It was a textbook case of a colossal business failure, and no one would touch it with a 10-ft pole. The judge hated to rule that a $5 billion infrastructure system burn up in the atmosphere, and luckily, at the last minute, Dan Colussy stepped in with a $25 million bid- less than half a cent on the dollar of initial construction costs, and swept it up.
Then what? The new Iridium Satellite LLC started cleanning up, which it's still doing. Very profitable. It turns out that, while it's impossible to recoup a $5 billion investment on a satellite phone system is impossible, recouping an investment 1/200 that size isn't so bad.
Can anyone tell me how to set my sig on Slashdot?
I'd just go down there for a week, talk with people, and pass out resumes.
That was the turning point of my life--I went from negative zero to positive zero.
The CPU is called the VIA C3 and the chipset is the VIA Eden. The "Athena" in your post refers to a Diamond Systems product name for the board which uses this CPU, not the name VIA calls their own CPU.
;-)
The "Mach86" you're thinking of is the ZFMicro ZFx86 chip. They are battling National Semiconductor, who produced these CPUs under contract for ZFMicro until ZFMicro was no longer able to pay their bills. Intel is not involved at all.
The other big PC/104 CPU vendors are Transmeta, STMicro (STPC), and AMD (Geode). Recently the Pentium 4-M have been popular for boards which don't need to support extended temperature.
PC/104 rocks for applications like this. Disclaimer: I work for a PC/104 company.
Can you tell us about the dramatic events of 17 May 2004?
By 17 May 2004 the AASTINO had worked remotely for 100 days in 2004, and then something went wrong...
The WhisperGen engine has a control panel connected to it using an RS-485 bus running on CAT-5 cable. The control panel contains a microprocessor, and the engine expects to communicate with it regularly (at least once a second). When this communication is interrupted, the engine shuts down and reboots its own microprocessor.
Unfortunately, this is what happened on 17 May. - the engine went into a cycle of rebooting every 40 seconds. Once the engine has stopped, we had a ten hour window in which to try to restart it before the 200AH lead-acid batteries would lose too much capacity and become too cold for a restart (which requires 15A at 24V for about 15 minutes).
During this period we worked feverishly to come up with a solution. Our first priority was to shut down all unnecessary power consumption in the AASTINO - we can do this via a series of Dallas one-wire switches which control power to all the subsystems. A call to the engine manufacturer came up with the suggestion that we wiggle the CAT-5 cable connection - we suspect they forgot that we were over 4000 km away from our engine!
The PC/104 computer was also on the RS-485 bus, and we reasoned that by rewriting the Linux device driver (which we had written in the first place, so we knew what we were doing) we could make the computer impersonate the control panel, and convince the engine that it should keep running. Fortunately, we had a snapshot of the communication traffic between the engine and the control panel from earlier testing in the lab with the manufacturer's MSDOS-based software. But with no hardware available to test our code, we had to modify the driver, send patches over the 2400 baud Iridium link, and rmmod/insmod the driver to try to restart the engine.
All the while, the internal temperature of the AASTINO was plumetting towards ambient, at about -60C. We first modified the driver to allow the link traffic to be analysed, and this confirmed the communication problem with the control panel. After several attempts at generating fake packets from the control panel, punctuated by breaks in the Iridium link and agonizing waits for the system to redial (it is dialout only, controlled by a crontab entry), we were unable to prevent the engine from rebooting.
We watched helplessly as the battery temperatures sank below the minimum threshold for engine restart. Over the next 24 hours we received the occasional connection from the AASTINO computer, but that was all. We are now hoping that the solar panels will be able to recharge the batteries suffiently to re-establish communication before the Dome C station opens for the summer.