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Green Bank Telescope Goes Live
ptbrown writes: "The world's largest steerable radio telescope is being dedicated today at Green Bank, W.Va. The 100 meter Robert C. Byrd Green Bank Telescope (named after a West Virginia senator) is 485 feet tall, weighs 16 million pounds, cost $75 million, took almost 10 years to build, and is expected to last for at least 25 years. The telescope it replaces (designed to last 10 years) collapsed in 1988 after only 26 years. This is a pretty unique dish: assymetrical, side-mounted feed arm, movable surface panels, and laser-assisted ranging. And they give tours, so if you're ever around southern West Virginia think about stopping by. "
What exactly is a 'radio telescope' anyway?
TK
"...the telescope it replaces (designed to last 10 years) collapsed in 1988 after only 26 years."
It was designed to last 10 and only lasted 26? They must have skimped on the corner-cutting.
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Linux MAPI Server!
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...because of the lack of, er, radio noise.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
It's not going to be used for any one thing in particular. With a telescope like this, groups will apply to use the telescope, then use for a short period of time, and then go and analyze their data. So there is no large set of data needing analysis like SETI@Home, only small sets of data for each experiment using it. So there's no need for a distributed computing environment to process the data.
the bum around the corner picks up signals from deep space with his little aluminum foil hat! that couldn't have cost more than $0.20..
...dave
Think different? I'd be happy if most people would just think...
Likely, there would be no gain....distributed processing of the SETI@home type is kind of unique in data analysis, being processor limited on relatively small amounts of data. Most large experiments (radio telescopes, particle accelerator detectors, etc.) have data analysis requirements that turn out to be bandwidth limited, and not processor limited; you end up having to move a few megabytes of data for each event of interest, but then you only need to spend relatively small amounts of time comparing a few of the pieces of data to a given criteria. Big collider experiments use large farms of cheap machines connected to very high speed networks to do their work, not something that scales well to low bandwidth networks like the Internet.
Obviously political arm twisting is why such a project ends up in West Va. (The New River Gorge Bridge was another example, which ultimately has paid off well for WV)
Question: Won't the RT's proximity to the east coast megalopolis suffer it interference problems: noise from jet traffic, radio, TV, etc.? I'm sure a certain amount of this can be filtered, but the less need for filtering the better, IMHO.
Vote Naked 2000
A feeling of having made the same mistake before: Deja Foobar
Isn't it sad that the telescope should be named for a senator (already famous) rather than a scientist?
Don't get me wrong -- I think it's better to have the telescope than not, even if you have to kiss a little senatorial hiney in order to get funding. Byrd was a respectable fellow. But it's a real commentary on the motives of America's politicians (who I think are underpaid and thus feel justified in seeking compensatory perks, like this one).
Sean
"With all these new telescopes were coming out with how come we cant use these to see pictures of like europa or pluto or something.... I guess we have no chance of ever spotting another planet around another star if we cant even barely see our own!"
IIRC, pretty much all the extrasolar planets (those not orbiting our sun) were observed via indirect methods. They'd aim the telescope at the star and measure the "wobbling" caused by the planet gravitationally tugging the star as it went around. Another method is the dimming effect a planet would have as it eclipses the star it orbits.However, I'd image big honkin' huge telescopes like that are optimized to look at stuff that's really really far away and not stuff that's relatively close like planets in our solar system. It's like how you really can't focus on something when it's right in your face -- your eyes don't work well at that close of range.
Also, this is a radio telescope, not an optical one. You wouldn't be able to see the planet anyway, although you could measure any radio emissions or radio reflections coming from its direction.
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The real Captain Derivative has a Slashdot ID.
"The 100 meter Robert C. Byrd Green Bank Telescope (named after a West Virginia senator)"
has been nicknamed, "The Porkbarrel" out of respect for the free-spending representative and his spending practices since arriving in Congress.
Besides the 75million taxpayer dollars for the telescope, 44 million dollars in highway improvements were also added to the area. In addition, 22 million dollars was allocated with the project to maintain West Virginia's Fort Wayne, the only US Army post still servicing stage coaches and mule wagons for our nation's armed forces. Finally, a 14 million dollar grant was included with the telescope money for a new medical study into the benefits of leeches in medicine for the University of West Virginia.
Thousands of the Senator's supporters turned out for the festivities including government subsidy recipient Marla Thornhill of Buck Hill, WV. "My tobacco farm would have been closed down if it had not been for the generosity of Senator Byrd. Without those tobacco subsidies, I would have to quit growing the stuff and switch crops. Millions of Americans have to be thankful for Senator Byrd's committment to the family tobacco farm".
Senator Byrd was expected to arrive later today aboard an Air Force C141 cargo jet along with 40 of his staffers before leaving for a fact finding tour of Bermuda for the next week.
Before coming to Transmeta, I worked for NRAO for five years (1993-1998). Some of that time was spent working on part of a software project (AIPS++) related to this telescope.
Most people probably don't realize the immensity of the software challenge that handling the amount of data this telescope will produce is. It's not just a monster piece of hardware--it's going to produce simply tremendous amounts of data; the software aspects of this unique telescope will be as interesting as its hardware aspects.
See Freeman Dyson's book Infinite in all Directions for evidence on how it's often the lower cost science that pays off best.
Helium balloons want to be free.
In this case, the scientific community will probably benefit, but I do wonder what the opportunity cost is...
sulli
sulli
RTFJ.
From personal experience, I can heartily recommend it.
;-)
It's worth a trip out of your way to take the tour. It is a beautiful area, not far from where I was born, and the tour is really interesting. They take you by the telescope SETI rents, and they have a flag out if they're listening while you're there. Only diesel engines are allowed in the area, because traditional engines generate electronic interference. The area also forbids microwaves or other devices with lots of RF noise. Plus there are cool T-shirts, a must-have for any geek.
In a crude sense, the bigger the size (huge with an array) the finer the resolution (think pizels). But the bigger the actual receiving area (actual metal the signal hits), the smaller the signal you can receive. It's a tradeoff. You spend money to get more of what you don't have.
For those who don't know what Greenbank is, also the home of other telescopes...these include
- 140 foot radio telescope (closed last July)
- GBI (Green Bank Interferometer)...a set of 85-foot telescopes
- OVLBI...a huge satelite tracking station.
Greenbank is one of 9 (If I remember correctly) tracking stations able to conmmunicate with the Hubble Space Telescope and is going to be one of the 2 or 3 major tracking stations for Arise - the next generation of space telescope.
Around the area is a military enforced "Quiet Zone". It is true that Green Bank is located in the "backwoods" of WV, but this is the reason for its existance. Belive it or not, this location is right up there with Arecibo in its usefulness to the astronomical community (maybe more so).
A few years ago I worked as a summer intern in Green Bank, WV at the NRAO installation. At the time, all that existed of the new telescope was a huge flat concrete pad. This post might be off-topic, but maybe I can convey something of what it was like to work there (not that my memory is perfect):
* The town (really two towns - Arbovale as well) is very small - a few hundred people, many of them employeed by the observatory. Unlike many small towns in Appalachia, these two towns do well economically because of the government spending there. There aren't many other towns around - they intentionally put radio observatories in places where there isn't a lot of interference.
* To track what radio interference there is, they have this truck that looks like an ice cream truck that's got some really outlandish antennas on it. This weird guy with a beard and sunglasses would slowly drive up and down the roads looking for interference. I'm sure it really freaked out the locals.
* More interference: at least when I was there, there were no gasoline cars allowed on the observatory grounds because the spark plugs (or something) interfered with the telescopes. Instead, there were these old diesel taxis - Checkered Cabs that are probably still used only in Havana these days. You could sign one out and they would generate huge blue clouds of exhaust.
* There was no hunting allowed and so there were HERDS of deer. Really. I rode my bike past herds of maybe 50 deer in fields, just eating and looking completely relaxed. If only I had had a blunderbus! There were several such groups. It ruined me forever for the novelty of seeing a deer - whatever! I saw hundreds of them.
* Sometimes, they would put this weird attachment on the 140' telescope that would quickly move the receiver back and forth about twice a second (I have no idea what it was for). It would make this intense, slow, drumbeat sound that would echo down the valley...kachunk...kachunk...kachunk.
* It was an excellent place for mountain-biking. The local mountains were at most a thousand feet tall and were covered in old logging roads in various states of disrepair. You could take it easy or really get a workout. * The people at the observatory were very nice and professional. It was a wonderful experience for me (I was there for computer work, not astronomy), but at the time - early 90's - we only had a modem-speed connection to the outside world! Ouch! * Some of the control computers (at least when I was there - maybe they've been replaced since) there are REALLY old - 60's era stuff. It was just easier to keep the old stuff running than connect new machines to the telescopes. There were hard drives that looked like washing machines and even a punchcard reader (a backup, not in active use). The new telescope, that just went live today, however, was slated to have the latest and greatest computer equipment.
That's all the I remember...Thanks for the memories, Slashdot!
For example, you could build particle accelerators until the cows come home searching for a fourth and fifth lepton family.
We don't. Why? Because physics + astronomy tells us that we have a certain percentage of helium in the universe, and the amount created during the Big Bang is very tightly constrained by the number of lepton families. Current helium percentages allow for three families, and just barely four if we squeezed and fudged the numbers.
The Universe is the poor man's particle accelerator, as the saying goes. Helium again: discovered as existing in the sun before it was found here on Earth.
The two sciences help one another. Killing one in favor of the other isn't helping either of them.
As soon as the local teenage yokels find out it's a 100 *meter* telescope, I'll bet they fill it with bullet holes.
Marco...that was Portugese.
Reknowned physicist siokaos made the shocking announcement today that radio waves are not, as had been previously thought, part of the electromagnetic spectrum.
"Radio waves pushed the real electromagnetic spectrum out of the way years ago," he said, "they fooled Einstein and Maxwell, but not me!".
siokaos is not sure what happened to the "real" electromagnetic spectrum, but he is currently working on the theory that they evolved into fish.
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E_NOSIG
A particle accelerator of the class that would actually be useful today would cost orders of magnitude more money than this telescope. Plus, I'd argue that there is always need for more telescopes -- getting time on any major scope is hard as hell (spoken like the bitter grad student I am), and there are a lot of things out there to look at. :-)
Actually, it's not a radiotelescope, it's an IRIDIUM satellite blasting particle emitter gun, constructed by the Secret Astronomer Cabal Dedicated to the Eradication of Iridium.
Maybe they can get a contract from Motorola for 'deorbiting' the birds...
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Arrays will produce a higher degree of resolution whereas a large dish will be able to detect fainter signals.
Although you have a larger surface area with the array, each reciever in the array is only recieving from one dish so the sensitivity of the array to a signal is the same as the sensitivity of one of the dishes. The effect is not additive. The advantage to the array is that signals can be taken from multiple points and run through a computer. An analogy would be making a 3D picture from two pictures taken at slightly different points. The new 3D picture has more information than the two 2D pictures. That's basically what arrays are good at. They compare different signals from the same source to get more information out.
Large dishes simply concentrate more energy on the reciever. This allows the reciever to see weaker signals than with a smaller dish. The array doesn't see the weak signal because each dish does not amplify the signal enough for the reciever to pick it up. Thus the signal is never seen.
Now if you could get the array of smaller dishes to focus the signal onto one reciever, then you'd have some power.
Remember, You are unique...just like everyone else.
This post brings me to my most interesting
feature request from slashdot.
Remember all the questions you asked when you
were eight years old ? ever heard any answers ?
Like what really is a radio telescope (answered
excellently at the beginning of the comments) ?
how does a photosensor work ? what *is*
bandwidth (i mean, is a property of wire? or is
it something to do with material? or what?)
or linguistics.
Even some excellent newbie tech questions. Like
TCP/IP stack or ray tracing or PCMCIA or
filesystems.
I am sure there are people out there who can
contribute a lot of good features to us by writing
up small features on a lot these kinds of
questions.
These features and the ensuing technical discussion, IMHO, will be far more interesting
than the licensing issues which are talked about
way too often.
Here's the nice, fluffy page. Somewhere near the bridge is a nice little museum, put up by the visitors bureau, which details the critical view of it as a pork-barrel project, as there was little traffic around the sleepy little town of Fayetteville prior to construction. Main benefit was expected to be for trucking, IIRC. However, the bridge can easily be defended now as it has brought whitewater rafters, bungee jumpers, hikers and much other recreational use revenues to the area. (Worth a few trips, to be sure.)
My bone of contention over the choice of WV for the Green Bank Radio Telescope is there are obviously much better locations, particularly in the west and at higher elevations.
But who knows, they may make tourist dollars, yet off this thing. Maybe there'll be a bungee jumping day...
Vote Naked 2000
A feeling of having made the same mistake before: Deja Foobar
Some of the other people here have already answered the basic question: a radio telescope acts much like an optical telescope, except it uses radio waves which then get converted into images by computer. Why use radio waves? For one thing, you can pick up emissions from warm interstellar gas that isn't hot enough to actually glow visibly; some of the basic ionization effects in the universe occur at specific microwave frequencies; and radio doesn't get as distorted as much as light does when passing through the atmosphere.
The real fun part comes when you start hooking multiple radio telescopes together to perform VLBI: Very Long Baseline Interferometry. By viewing the same object from multiple locations, you can pick up details that either telescope by itself would have missed. The more radio telescopes you have, and the further apart they are, the better resolution you can get on the final image.
For really long baselines, the Japanese launched a radio telescope up into orbit a few years back. By itself it's not all that good; radio telescopes don't get as much of a boost from being outside of the atmosphere. But combine that with telescopes on the ground at the same time, and the combined system has a resolution over a hundred times better than the Hubble. People have actually managed to pick up details from quasars that nobody had been able to see until recently.
Of course, you can also reverse VLBI: once you have a quasar or some other highly distant object mapped out, you can invert the calculations and determine the exact relative locations of the telescopes from a new observation. This means, for example, you can determine if two telescopes have moved further apart since the last time you looked at this quasar: you can track continental drift. Or the rotational period of the Earth to sub-millisecond precision. Or there's been talk of using radio telescopes and VLBI to help correct for phase drift errors in GPS satellites.
Not to mention some of the other work on tracking space debris and meteors by using radio telescopes...
-- Bryan Feir
There's a West Virgina senator named Green Bank?
Why such a large dish? I am not a radio astronomer, so I am sure there is a good reason. I understand that it is a large parbolic reflector, and of course the bigger it is, the more it can gather. I also like the idea of the single arm mount (damn that thing is HUGE!)...
Why did they choose to build it this way, instead of a large array (such as done in NM)? Is it because errors or other anomalies are introduced into the data when the individual data streams are "combined" in an array - that might mask something or another?
Please, someone - enlighten me!
I support the EFF - do you?
Reason is the Path to God - Anon
There are some cool pictures of the 300ft one that collapsed here