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Robotic Telescope Installed on Antarctica Plateau
Reservoir Hill writes "Antarctica claims some of the best astronomical sky conditions in the world — devoid of clouds with steady air that makes for clear viewing. The very best conditions unfortunately lie deep in the interior on a high-altitude plateau called Dome A. With an elevation of up to 4,093m, it's known as the most unapproachable point in the earth's southernmost region. Now astronomers in a Chinese scientific expedition have set up an experimental observatory at Dome A after lugging their equipment across Antarctica with the help of Australia and the US. The observatory will hunt for alien planets, while also measuring the observing conditions at the site to see if it is worth trying to build bigger observatories there. The observatory is automated, pointing its telescopes on its own while astronomers monitor its progress from other locations around the world via satellite link. PLATO is powered by a gas generator, and has a 4000-litre tank of jet fuel to keep it running through the winter. The observatory will search for planets around other stars using an array of four 14.5-centimetre telescopes called the Chinese Small Telescope Array (CSTAR). Astronomers hope to return in 2009 with new instruments, including the Antarctica Schmidt Telescopes (AST-3), a trio of telescopes with 0.5-metre mirrors, which will be more sensitive to planets than CSTAR."
I find it interesting that they decided (probably pretty intelligently) that the eaeiest way to do this project was robotrically, instead of trying to man a mission to antarctica through the winter.
i wonder if the same theory was applied to space travel would a mars mission be logically manned or not?
My guess is just to prove we can, rather than actual practicality, which I'm all for because it pushes out the boundaries of what we know, and sets a goal.
That said, i couldnt help thinking of the similarities of hostile environments. (without the distance issues)
There's nothing Intelligent about Intelligent Design.
Actually, I think I'd prefer an RTG reactor like they use on long-range satellite probes. No CO2 emissions, lasts longer, and any heat you don't use to generate electricity can be used to warm the equipment.
You're right, it was liters. 4000 of them.
I'm one of the 4 UNSW scientists who designed PLATO. We certainly are using the fuel efficiently. When the sun is up we get over 1kW from solar panels, and we run one diesel generator at a time with just enough heat output to stop the fuel from getting too cold and turning to gel. Interestingly, the solar panels are considerably (about 30%) more efficient than you would expect from temperate site measurements - the colder temperatures (-50C at the moment) help, as does sunlight reflected from the snow.
Well, you have to start somewhere! Remember that Dome A is completely remote. There is no station there, and PLATO is running without human intervention for as long as a year. The amount of fuel we could take in dictated the available power, and that in turn limited the size of telescope we could take in. Still, we have four 14.5cm telescopes, a 1.5m sonic radar, two sky cameras, 4 webcameras, a 15-m tower, and a 450 micron wavelength telescope, several terabytes of disks, a dozen computers, about 64GB of flash storage, two Iridium satellite modems.
Hazah! I'm really surprised to get a response from a project participant, and thrilled with your answer. I wish you best of luck with the project!
Goofing off for the last 20 minutes or so of the day.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Why did you not consider wind power? I'd imagine it would be quite strong and even winds there, and no neighbours to whine about the ruined view.
c++;
Getting the scientists there and back uses more jet fuel than this.
Environmentalism is a noble and necessary cause but if you're going to make cost savings try ellminating things like Christmas lights before you decide to object to science like this on environmental grounds. We wouldn't know about environmental impact if we didn't do good science.
These posts express my own personal views, not those of my employer
Nice to see that you took care to make efficient use of the fuel, but did you guys find the remains of any Elder Things?. What about shoggoths? They're pretty nasty if you thaw 'em out.
I write sci-fi for metalheads
As one of the University of New South Wales people involved, I thought slashdot might like some information on the computer systems that PLATO uses.
PLATO uses two redundant PC/104 form factor computers running Debian Etch. The computers boot from a 4GB flash disk (we tested 5 different models in the lab, and found one that worked reliably to -60C, despite only being spec'ed to -25C; all the other models worked to -40C, but had problems below that).
We use a readonly filesystem, with /home, /etc, and /var being created on boot in a ramdisk. This works really well, and it is nice to be able to turn off the power at any time without being concerned about filesystem corruption. Needless to say, with no possibility of any human being on-site for the rest of the year, we have thought very carefully about reliability.
Bulk data storage is provided by terabytes of conventional disks, with the most precious data being backed up on ~64GB of USB flash disks. Conventional disks don't handle the altitude very well, so we don't like to rely on them.
Communication is via two Iridium satellite modems, running at 2400 baud. We can push software updates by sending a set of "Short Burst Data" messages of up to 2000 bytes at a time. We can also login to PLATO using ssh, and I'm logged in as I'm typing this and running experiments.
There is a CAN (Controller Area Network) bus running throughout PLATO and linking the two modules: the Instrument Module, and the Engine Module, 45m apart. Each of 11 nodes on the bus has a small Atmel board that can turn power on/off to experiments, digital and analog I/O, etc.
More info, photos, and links to the health and status data are at http://mcba11.phys.unsw.edu.au/~mcba/plato
Actually, Dome A is one of the least windy places on Earth, typically just 2-3 metres per second. Dome A is the highest point in the centre of the Antarctic plateau, and this is where the katabatic winds start from. The winds accelerate as they head towards the coast, and that is where they can reach 100's of kph.
So, unfortunately, wind power was not feasible.
The decision to use "jet fuel", specifically Antarctic grade kerosene, was made by the Australian team after much consideration of all reasonable alternatives. Environmental issues were foremost in our minds. PLATO produces a microscopic addition to the kerosene usage in Antarctica. We are using efficient diesel generators, and have over 200mm of additional insulation lining both modules of PLATO. Every 15 watts of heat we put in raises the internal temperature by 1 degree C.
We have 1kW of solar panels, which provide most of the power during summer. However, when the sun is down, and with the very low windspeeds at Dome A, the choices become limited.
We will eagerly embrace hydrogen fuel cells when they become practical. However, they are not there yet.
Actually, I think I'd prefer an RTG reactor like they use on long-range satellite probes. No CO2 emissions, lasts longer, and any heat you don't use to generate electricity can be used to warm the equipment.
IANAA (I Am Not An Astronomer), but I would think there would be less distortion if the optics were actually at the same temperature as the ambient air temperature.
Also, if you're doing any sort of spectroscopy, you'd want your detector to be really, really cold and that would be easier to attain in the Antarctic winter. I remember a buddy of mine at NASA/GSFC who worked on a spectroscopy apparatus, and their detector was vacuum insulated and cooled using liquid helium, IIRC.
"Ein Volk, ein Reich, ein Führer." -Adolf Hitler
"We are one Nation, we are one People." -The One 'leader'
With two modems going flat out we could theoretically transfer 40MB per day. In practice the link isn't all that reliable and we would be lucky to achieve half of that. Still, it is enough to control the experiments and return reduced data to verify that everything is working. All of the health and status information fits into 12KB per day.
The bulk of the data will be physically returned by the next Chinese traverse team, this time next year.
IAAAA (I am an amateur astronomer) and yes, you want the equipment at the same temp as the surrounding air. Otherwise, the equipment will create a local air current, which would cause optical distortions.
I'd give you mod points for your answers but there seems to be no category for comments that are simultaneously informative, interesting and insightful. Therefore, I'll just extend thanks on behalf of all of us who will benefit from this extension of knowledge and wish you great success and excellent karma.
The engines are Hatz 1B30, we use two different generators: four are made by eCycle, and two by Mavilor. Each puts out about 1kW at 120VDC.
To start the engines we have two banks of Ultracapacitors. These are amazing devices, 3000 Farads each, charged to 2V, with 12 in each bank arranged to give 12VDC. They can turn over the engines very quickly. We haven't had to crank an engine for more than 2 seconds yet, although we haven't dropped the engine temperatures below 0C.
We tested the system in a pressure tank at UNSW to simulate the roughly 0.5atm pressure. The engines still work well at this altitude.
For your interest, here is some information on how PLATO got to Dome A.
The PLATO modules were built at the University of New South Wales in Sydney, Australia. Instruments were provided by our collaborators at a number of universities in China, the US, and the UK.
In late November 2007 PLATO was trucked 3912 km to Perth, where it joined a Chinese icebreaker for a two week trip to Zhongshan station on the edge of Antarctica. A helicopter then lifted the modules off the ship and about 100km inland where they joined a traverse for the ~1200 km journey to Dome A.
The traverse was an amazing feat. 17 people, 5 tractors. PLATO itself weighted about 10 tonnes. The traverse moves at speeds of 5-10 km per hour each day for 10 hours, and then rested for 14 hours. After three weeks of this, they arrive at Dome A. I am told that the undulating motion of the tractors over the ice can give you "sled sickness", an unpleasant variety of seasickness.
The team spent 10 days at Dome A, and did a fantastic job of installing the experiments and getting everything working. The temperatures were around -30C, which isn't much of an issue at low wind speeds. The altitude (4090m) is more of a problem, as it makes physical work exhausting, and there are difficulties with sleeping, mental acuity, etc.
Much more information, and a diary of the trip by the Chinese team members, is at http://mcba11.phys.unsw.edu.au/~mcba/plato.
As for astronomy, the team running this automated experiment at Dome A did it previously at Dome C. I was on the first winterover team in 2005 and monitoring the turbulence for astronomy was one of the main goals. Bigger telescopes are being installed as we speak in time for the start of the 4th winterover in a few days.
Dome A is 1000m higher than Dome C (4200m vs 3200m) but is even harder to reach and the temperature in winter borders on the insane: we had -78C during our winterover so I'll let you imagine at Dome A...
Non-Linux Penguins ?
The problem with gasoline in those temperatures isn't so much that it gets more viscous--jet fuel gets much more viscous, in fact... The thing is, at those temperatures, gasoline isn't volatile enough to readily burn in an engine, and the compression stroke of a gasoline engine doesn't provide enough heat in those temperatures to elevate the atmosphere in the cylinder to a high enough degree to let the fuel normally burn.
Diesels engines are what make power down there, because 1) the compression stroke does provide enough heat to ignite diesel-like fuels. 2) they're more efficient.
They use jet fuels because they're compatible with icing inhibitors--and proper diesel engines don't mind.
Has your team considered puting the hard drives in a pressure vessel of some sort?
Yes, we have thought about this a lot, and have never had the time to complete the design! It is the best solution, and we should be doing it. It is much easier nowadays that IDE interfaces are going away and serial connections mean that fewer cables need to leave the pressure vessel.
If we use a USB interface, I'm a bit nervous about the reliability of Linux USB storage, or perhaps it is the controllers that interface the drive with USB. I've had many examples of filesystem corruption with external USB drives. And USB flash disks seem to have problems too. Quite often during boot a drive will give all sorts of error messages and will require power cycling to fix it. Googling for these problems show that they are common, but with no solutions that I have found.
Our particular PC/104 computer has both USB 1 and 2 interfaces, but we can only boot reliably off USB 1, and we see intermittent failures if we use both USB 1 and 2. The flakiness of USB for storage is a major frustration.
SATA wasn't an option on our computer. These are low-power embedded systems, so they tend to lag a bit with some of the newer interfaces.
Do you expect the seeing to be significantly better at Dome A than Dome C ? Do you know if the turbulent layer is lower than the 30m of Dome C ? Is there winter weather information available since the chinese first set foot there in 2005 (I'd expect they left an AWS) ?
I hope you have improved the reliability of your equipment and that it didn't get too banged up during transportation. Anyway, good luck with this experiment. Has the traverse team turned tail already ?
Non-Linux Penguins ?
Hi Guillaume, good to hear from you! (Slashdotters - do yourself a favour and visit Guillaume's website and have a look at some of his amazing photos). We aren't currently running anything at Dome C. Dome A is likely to have similar seeing to Dome C above the boundary layer, but the layer is expected to be lower, possibly touching the ice. That is one of PLATO's prime goals - to measure the height of the boundary layer with a sonic radar.
The Chinese took an Australian Antarctic Division AWS to Dome A in 2005.
Yes, the reliability of our equipment continues to improve. It is now even better than the stuff we took to Dome C!
We mounted everything on shock absorbers to survive the 1200 km sled trip. There was no damage.
The traverse team should arrive back in Zhongshan station today.
Well said. But don't worry about excellent karma for Prof Ashley, I've never seen a Slashdot User profile page with more +5 posts in a single thread in my life! (Darth Vader voice) "Impressive, most impressive".
The equipment is quite modest by many standards, what impresses me is what they were able to make it portable, then freakin' sled it to one of the most remote spots on the planet. What other telescope is in a spot so completely away from artificial lights?
I wonder what sort of image noise will be created in the images by the Aurora Australis. Or might the effect be negligible?
I mean, the only other astronomical endeavor I can think of that was done close to either the Arctic or Antarctic Circle was in Alaska, a couple of kilometers down a mineshaft, during another species of beast altogether - the neutrino hunt. Who knows, maybe that mine is still being used for that purpose.
Then, when the telescope is up and running, for every single observation there's calibrating, aligning, doing the time exposures... oh dear. These things are difficult enough with a crew right by the telescope. I have a friend who hasn't been able to get a single night's worth of useful data in the last four or five trips to the big telescope in my neck of the woods - the UNAM Observatory in San Pedro Martir, Baja California. Seems like every time she goes up there, something goes wrong.
Buckle up, people, it's gonna be a wild ride Down Under! Needless to say, I'm thrilled and fascinated by the whole thing.
Lil' Thindime, lilting a lacrimose lament, krashes the kwaint konfines of Kokonino Kounty