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It wasn't NASA, it wasn't ESA and it wasn't easy...

One of the backups, in this case, is the Robert C. Byrd Green Bank Telescope. I imagine that the telescope is located on Robert C. Byrd Highway, down the road from the Robert C. Byrd FBI Fingerprinting facility and just around the corner from the Robert C. Byrd Memorial High School.

Man, the Esteemed Senior Senator from West Virginia sure does a fine job of delivering the bacon...

"In 1895 Bose gave his first public demonstration of electromagnetic waves, using them to ring a bell remotely and to explode some gunpowder. In 1896 the Daily Chronicle of England reported: "The inventor (J.C. Bose) has transmitted signals to a distance of nearly a mile and herein lies the first and obvious and exceedingly valuable application of this new theoretical marvel." Popov in Russia was doing similar experiments, but had written in December 1895 that he was still entertaining the hope of remote signalling with radio waves. The first successful wireless signalling experiment by Marconi on Salisbury Plain in England was not until May 1897. The 1895 public demonstration by Bose in Calcutta predates all these experiments. Invited by Lord Rayleigh, in 1897 Bose reported on his microwave (millimeter-wave) experiments to the Royal Institution and other societies in England."

"Although it appears that Bose's demonstration of remote wireless signalling has priority over Marconi, he was the first to use a semiconductor junction to detect radio waves, and he invented various now commonplace microwave components, outside of India he is rarely given the deserved recognition. Further work at millimeter wavelengths was almost nonexistent for nearly 50 years. J.C. Bose was at least this much ahead of his time."

Obligatory disclaimer: I wrote this humble file formats FAQ and it represents my personal and professional opinion (not necessarily my employer's).

That said, can someone in MA please ask the movers and shakers there to read that document? It's probably in the class of "common sense" to most of us here, but clearly we've done a less than stellar job so far of imparting this clarity to those in political circles.

For the impatient: the conclusion I reached is that RTF and PDF are very questionable if you want to use them as truly interchangeable formats in a heterogeneous environment. This is an empirical finding, based on real life experience.

Because you don't have a 100-meter dish receiving the signal, like the Green Bank Telescope.

This wattage/mile efficiency thing is always a neat trick. I doubt however, that anyone can beat what must be a record of some sort: the detection of the 10 watt (mostly) non-directional radio transmitter atop the Huygens probe while falling into the atmosphere of Titan by the Very Long Baseline Array when nearly 1 billion miles away. A feat expected to be achieved next week. The power collected by one of the 70 meter dishes on earth will be comparable to what was detected from the feeble low gain antenna on the Galileo Jupiter probe. This power is in the ZEPTOWATT range. (zeptowatt)

In addition to this, the VLBA will be used in interferometer mode (VLBI) in order to pinpoint the landing site of the probe on Titan to within 1Km!! This is equal to an angular resolution of approximately 170 microarcseconds. Thousands of times better than Hubble.

...At a lonely and near-deserted monitoring station hooked up to the VLA, a single technician jerks out of his half-asleep doze in utter amazement.

Why, you may ask? Well, you'd be amazed too if you were in a similar situation, and you suddenly heard, emanating from the ether in the general direction of Mars, a bunch of reedy chipmunk-pitched voices raised in a glorious chorus of --

"Car Wash.... Workin' at the Car Wash, yeah..."
(Work, And Work)
"Keep those NASA Rovers comin!"
(Work, And Work)
Keep those dusty panels comin..."

(You get the idea. I'm going to go to bed now...)

Machine number one will go to Livermore, probably for doing some nuclear stuf. Number two will go to the Netherlands for the Lofar project. This is a 300 kilometer diameter radio telescope that observes at low frequencies (up to 250 MHz). It constists of thousands of small antennas spread across half the country. Their signals will be interferometrically combined to form the images (compare e.g. to the VLA). Blue Gene will be used to combine all the signals in real time, I believe the total bandwidth from the antennas is some terabyte/sec.

The NRAO's headquarters are in Charlottesville, Virginia, and have been for a very long time.

The NRAO has facilities in a variety of locations, of which Green Bank is one.

Apparently you can build the largest (100 meter) steerable radio telescope for 75M$. Arecibo is not steerable and is build in a valley, so it will probably cost less than that. Add in a few dozen smaller dishes all over the world, probably costing less than 30M$ each for a small one. Add some bandwith costs, supercomputers and other fancy equipment. Grand total for all hardware worldwide won't be much more than 1B dollar, or about 1 or 2 shuttle launches without the cost of a hubble.

However, that does not mean that you could ditch Hubble and its colleagues: Hubble observes at visible wavelenths (~500 nm), radio telescopes operate at wavelengths of some centimeters. This lets you observe totally different physical properties of stars. The two techniques are thus complementary, for good science you need both.

It is also important to understand why you need big telescopes spread all over the world to obtain roughly the same resolution as hubble's two meter dish: resolution scales with (wavelength/diameter). To obtain a better (smaller) resolution, you need a smaller wavelength or a larger diameter dish. Instead of building one really large disk, you can also build several smaller and place them far apart.

I'm a radio astronomer, so maybe I'm biased, but you can't say optical gives more useful scientific data than radio. No way. If you need to look in the optical, you do. If you need to look in the radio (because something is only visible in the radio, like a pulsar), you do that. And as for making pretty pictures, Hubble may be the ultimate, but radio telescopes can give some impressive results. Check out the VLA image archive

This sugar (glycoaldehyde) + a 3 carbon sugar = ribose = a building block of deoxyribonucleic acid. See the original link

Note: Images are hosted through nyud.net to avoid funding spam

A cloud filled with simple molecules of sugar has been found 26,000 light-years away from us, near the middle of our Milky Way Galaxy. The 8-atom sugar molecules exist in a gas cloud named Sagittarius B2 at a temperature of only 8 degrees above absolute zero. Too far and too cold to bake your next cake! However, even if chemistry reactions on Earth and in this frigid sugar cloud are very different, astronomers think this "discovery suggests how the molecular building blocks necessary for the creation of life could first form in interstellar space." I'm not qualified to say if their claims are funded, but don't hesitate to tell me if they're right or wrong.

Please read the original article for more astronomical details or just enjoy the illustrations below describing how prebiotic chemistry -- the formation of the molecular building blocks necessary for the creation of life -- occurs in interstellar clouds.

The above acronyms in the credits for the illustrations refer respectively to the National Radio Astronomy Observatory , the Associated Universities, Inc. (AUI) and the National Science Foundation (NSF) .

Sources: SpaceRef.com, September 20, 2004; and various websites

here

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I am somewhat involved with the European version of these missions (the Darwin mission, to be launched around 2014), so I might clear some things up.

Goal: to detect earth-like planets around other starts. Extra-solar planets detected thus far are usually 'hot Jupiters': big planets that orbit the star in a few days. These are relatively easy to detect. Detecting an earth-like planet (which have not been found yet) is far more difficult. It is usually compared to detecting the light of a firefly (reflection of the planet) flying very close to a lighthouse (the star). Measurements need to be done in the far infrared because there the ratio between the planet and the starlight is the highest (but still only 1:10^6 !!). With some luck they might find traces of ozone and CO2 in the spectrum that might be an indication for life.

Methods:
-Coronography: Simply put it is just a conventional big (~10 meter) telescope with a shadow mask that blocks the light of the star. The light of the planet should get past the mask on the detector.

-Interferometry: Somewhat similar to the techniques used in radio astronomy. The resolution of a telescope improves by increasing its size. The trick is to combine several small telescopes. The resolution should then be comparable to the resolution of one big telescope that is as wide as the separation between the small ones. With radio interferometry you can do the 'beam combination' by computer. In optics however you have to physically combine the beams of the different telescopes. This requires flying satellites in formation with stabilities on the order of nanometers!! Current schemes are limited to several hundred meters. There are also some attemps to do this on earth.

There is quite a lot of politics going on between NASA and ESA at the moment about how they should cooperate. First ideas where to do an interferometry mission together, but now NASA has decided to go for coronography and postpone interferometry to 2020. ESA is sticking to interferometry.

NO! Read my other post and get your names correct before you start going on about "knowing nothing about astronomy".

The VLA is the Very Large Array, a RADIO telescope run by the american National Radio Astronomy Observatory (or NRAO). It is certainly NOT run by ESO, which is the European Southern Observatory, the organisation that runs the 4 8m Very Large Telescope (VLT) telescopes in chile.

There is no other complete solution to avoid atmospheric turbulence (i.e. seeing and scintillation) other than going to space. A *partial* solution is to use deformable mirrors in an adaptive optics to attempt to correct the problem.

Even with multiple-conjugate adaptive optics (which use multiple laser guide stars to improve performance), you will NOT get diffraction-limited images on an 8m telescope.

Crisper images taken from space will only be better if the diffraction limit of hte telescope is better than what can be obtained by a ground-based system using AO or MCAO. Although nobody has a working MCAO system yet.

sorry, sounds a bit much like a rant, but might add some helpful info into the discussion...

NO! Read my other post and get your names correct before you start going on about "knowing nothing about astronomy".

The VLA is the Very Large Array, a RADIO telescope run by the american National Radio Astronomy Observatory (or NRAO). It is certainly NOT run by ESO, which is the European Southern Observatory, the organisation that runs the 4 8m Very Large Telescope (VLT) telescopes in chile.

There is no other complete solution to avoid atmospheric turbulence (i.e. seeing and scintillation) other than going to space. A *partial* solution is to use deformable mirrors in an adaptive optics to attempt to correct the problem.

Even with multiple-conjugate adaptive optics (which use multiple laser guide stars to improve performance), you will NOT get diffraction-limited images on an 8m telescope.

Crisper images taken from space will only be better if the diffraction limit of hte telescope is better than what can be obtained by a ground-based system using AO or MCAO. Although nobody has a working MCAO system yet.

sorry, sounds a bit much like a rant, but might add some helpful info into the discussion...

TORG was sweet but DC Heroes trumped it.

DCH had a log scale AND a 3x3 matrix for your character attributes - that was the cartesian product of type (physical, spiritual, mental) and function (accuracy/speed, power, resistance/capacity) - and therefore it had a single task resolution that encompassed magic and combat.

The system had to be good because it had to work for every character in the DC universe. It was soo good that when Mayfair (the creator) and DC killed it off, the system (sans the superheroes) was licensed by an upstart company.

Here is the current incarnation of it.

Reference at U.S. National Radio Astronomy Observatory Apparently IEEE also recognized Bose's contribution to Radio. Maybe a someone with access to IEEE material (Google has not helped me) can substantiate this.

You're absolutely right that we don't hear as much about radio astronomonical observations. There are probably a few reasons. The first stems from the fact that astronomers tend to specialize in a given waveband -- the knowledge and expertise that is required to observe in the optical is very different from that required to observe in the radio, and both are in turn radically different from that required to observe in gamma rays. A few exceptionally talented astronomers operate in a couple of bands, but almost none operate across the entire spectrum. Radio astronomers are a minority within the astronomical community, and while they do really great science, it is primarily on sources filled with cold gas or electrons gyrating in the magnetic field, and are somewhat more difficult to popularize than a snazzy Hubble photo. The other reason, I think, is largely cultural and political. NASA does a great job pushing its science (Hubble, Chandra, Spitzer, planetary missions) to the public's attention, and devotes a lot of its effort culling the media's attention. The remainder of the astronomical community, including the national radio and optical observatories, tends to be much more conservative, and does not make much of an effort to garner attention. Generally you will only hear of their work when the press appears at one of the American Astronomical Soceity (AAS) and snatches up a few of their stories to splash up in their papers and broadcasts.

This parent posting was really great, and I applaud the moderators who modded it up. However, sadly, it was the ONLY reasonable post modded at 5 -- the rest are just a bunch of idiots making stupid comments which some other idiot found funny. Posters and moderators should definitely try harder to keep postings on topic and technically worthy. That is, after all, what slashdot is all about.

Bob

Hey you, second from the far right, Get with the programme!

I remember seeing a photo of this array as a child. Back then it only had five dishes. I had no idea that it had been filled out. Why don't we hear about this sort of thing?

breaks new ground in digital photography by combining metadata, like location via GPS, with the image.

Wait a minute. "Breaking new ground by... combining metadata with an image"????

Sigh. Astronomers have been doing this since at least 1981 with the FITS Format. See over here for the full story on this venerable and still very much in production format.

I sure hope M$ doesn't try something silly like a patent on this; it seems to me that FITS and the other formats used by the Medical and Geophysical Sciences would provide a wealth of prior art...

It would be difficult. I think you're talking about interferometry. This was originally developed for radio telescopes, and is harder to do at shorter wavelengths. The Submillimeter Array, working at the shorter submm wavelengths, has just opened on Mauna Kea, although some work has already been done with linking the James Clerk Maxwell Telescope and the Caltech Submillimeter Observatory. At optical wavelengths it gets harder still. An example is the Cambridge Optical Aperture Synthesis Telescope (COAST). There's also the proposed `Ohana project.

A major problem is that you have to preserve the phase information of the light when you combine the signals from the telescopes, so you can't just record images with a CCD (which only gets you the intensity) and then try to handle the rest of it in software.

Essentially this means that you'd have to combine light from the telescopes in real time and keep the path lengths between them accurate to a small fraction of the wavelength you're measuring. You can do this "off-line" at radio frequencies, for example with the Very Long Baseline Array (VLBA) but not at optical frequencies.

So, in summary, the Internet lets amateur observers collaborate in various ways. However, combining their optical telescopes to get the resolving power of a larger telescope (the size of the distributed collection of individual telescopes) through optical interferometry is not one of them.

Jocelyn has also won her fair share of other (not as prestigious) prizes. Almost ten years ago, she gave the "Jansky lecture" awarded annually by the National Radio Astronomy Observatory to someone who has made outstanding contributions to the advancement of astronomy. I agree with Scott -- the majority of astronomers that I talked to before her talk told us that she had been unfairly treated by the Nobel committee. I think that the astronomical community has done their best to try and right this wrong. As an aside, most of the Jansky lectures that I attended were awful. Jocelyn's was the first that I saw, and hers was outstanding.

Ah. Then IHBT. IHL. HAND. Glad to hear your trip went well, though.

My girlfriend and I recently took a three week cross-country road trip (pictures here), and visited the following destinations (they aren't entirely geeky, but there are some geeky spots along the way):

Tallahassee, FL -> Madisonville, LA -> Austin, TX -> Elephant Butte, NM (silly name, cool place!) -> Williams, AZ (stopped to see the Very Large Array (VLA) on the way, near Magdalena, NM -> Grand Canyon, AZ -> Las Vegas, NV -> Yosemite National Park, CA -> San Francisco, CA (lotsa fun geeky stuff here) -> Lake Tahoe, CA -> Elko, NV -> Denver, CO -> Oklahoma City, OK -> Tallahassee, FL

I highly recommend this trip, as you get to see a lot of things in a fairly short amount of time. Some tips (in no particular order):

- Buy a national parks pass. See my other post for more information.
- In desolate areas, keep spare gas with you. Five gallons should do nicely, unless you have an SUV.
- Bring a camera. A digital camera is preferred, and a 128 MB picture card (or more) is highly recommended if you are using a digital camera.
- Go camping. All motels, regardless of location, are pretty much exactly the same -- four walls, a bed and a shower. Camping is different wherever you go.
- Carry a AAA membership. They can get you out of many hairy situations.
- Ride with two or more people. This makes the trip that much more fun, because you can share the experiences for a lifetime. It's also much safer to travel this way.
- Many of my other recommendations are here -- they are equally important to having a good trip.

Happy travels!

For natural wonders, it's hard to beat Grand Canyon National Park. And while you're in Arizona/New Mexico, check out one of the ancient Anasazi Indian sites like the Chaco Culture National Historical Park in Nageezi, NM or Mesa Verde National Park between Cortez and Mancos, CO. For a technically geeky side trip, you could visit the National Radio Astronomy Observatory Very Large Array about 50 miles west of Socorro, NM.

Greenbank Observatory is located in the gorgeous mountains of West Virginia and hosts the world's largest fully steerable radio telescope !! What could be more geeky?

Definitely, the Very Large Array radio telescope outside Socorro, New Mexico. Also Kitt Peak National Observatory,/a>.

It's Very Hard To Get To
The Very Large Array has a nice but small visitor's center. You can also watch the individual dishes move all in unision.
The VLA is also way out in the middle of nowhere, so you can spend a lot of time hiking in New Mexico.

Two definitely geeky things to check out in New Mexico.

The Very Large Array - Gigantic Radio Astronomy installation

The Trinity Test Site. Only open a few times a year, your chance to see where the first atomic bomb was tested.

No, you're wrong. Hertz discovered RF. Bose used that research to invent a "mercury coherer" and Marconi simply ripped it off. Another Link

To clarify:

Antenna beam width is inversely proportional to apeture size. Building several small antennas and hooking them together as an array (like the VLA and VLBA do) increases the apparent apeture size (although it has a very bad fill factor!), reducing the beamwidth of the composite antenna.

Furthermore, increasing the apeture size also increases sensitivity by increasing the total received power. If an antenna with an effective apeture of one square meter receives a signal of -100 dBm, using an antenna with an effective apeture of two square meters would double (+3 dB) the received power (to -97 dBm), all else being equal. Likewise a four-square-meter apeture would provide 6dB of gain relative to the 1 square-meter antenna.

Finally, it's easier and less expensive to build and use multiple smaller antennas than one big honkin' antenna. The dishes of the VLA are steerable; they can see more of the sky. Arecibo is not nearly as flexible.

To clarify:

Antenna beam width is inversely proportional to apeture size. Building several small antennas and hooking them together as an array (like the VLA and VLBA do) increases the apparent apeture size (although it has a very bad fill factor!), reducing the beamwidth of the composite antenna.

Furthermore, increasing the apeture size also increases sensitivity by increasing the total received power. If an antenna with an effective apeture of one square meter receives a signal of -100 dBm, using an antenna with an effective apeture of two square meters would double (+3 dB) the received power (to -97 dBm), all else being equal. Likewise a four-square-meter apeture would provide 6dB of gain relative to the 1 square-meter antenna.

Finally, it's easier and less expensive to build and use multiple smaller antennas than one big honkin' antenna. The dishes of the VLA are steerable; they can see more of the sky. Arecibo is not nearly as flexible.

Thus "unlimited bandwidth for everyone" doesn't seem as economical, especially if your receivers are really expensive.

Thus "unlimited bandwidth for everyone" doesn't seem as economical, especially if your receivers are really expensive.

*looks at crotch*
*looks at map of West Virginia*
*looks at crotch*

Nevermind.

There is another very important point to recognize here. The HST Key project results (based upon Cepheid variable stars) is independent of the measurement/modeling of the ages of the oldest stars of Milky Way halo stars and clusters. Sure, both measurements each have significant systematic errors, but their uncertainties come from entirely different things! So the fact that they agree is quite reassuring. It also means that the measurements can be combined, at least to some degree.

With the newest generation of instruments and telescopes observing the Universe from radio waves to gamma rays, there will be new, independent methods of measuring the age and fate of the Universe. Already measurements from Type 1a supernovae are narrowing the uncertainties in some cosmological parameters. Other methods that currently yield very large error bars, but will be pivotal in the next few years are gravitational lensing (a detailed description here) and the Senyaev-Zeldovich effect (some details here).

When and if we get to the point where all methods yield the same result, we'll have our answer. In the meantime, if you just quote the formal results from just a single group, from a single type of argument/measurement, the systematic errors are going to be large, particularly when you're dealing with anything on cosmological scales!

1) Big Brutus, in West Mineral, Kansas - the second largest electric shovel in the world, and (IIRC) the only one still in (more or less) one piece. If you are in Branson, MO you are a couple of hours out.

2) The Kansas Cosmosphere and Space Center, Hutchinson, Kansas. See where Apollo 13 and Liberty Bell were restored, and (in a couple of months) watch them restore a V2 rocket (and even help them do it!). (While here, if it isn't Sunday, get directions to The Carrage Crossing restaurant).

3) EBR-1 the world's first breeder reactor, and the first reactor to make electric power, just outside Arco, Idaho (first city to be powered by nuclear power) (while here, you can go through Craters of the Moon National Park, one of the places that the Apollo astronauts trained. Stay in the DK inn, and you have a good chance of staying in one of the rooms they stayed in).
4) The Very Large Array, outside Socorro, New Mexico. While here, you could also go through White Sands National Park.
5) The London Bridge V2.1 in Lake Havasu, Nevada, where the entire London Bridge was relocated to.
6) The Jefferson National Expansion Memorial a.k.a. The Saint Lewis Arch - there is quite a museum below the arch, and I found it mind-blowing to realize that Saint Lewis is an ocean port.
7) Mount Rushmore National Park - go through the Rushmore Borglum Story for how they carved it and the tricks Borglum used to make the faces look more alive. While there, stop by....
8) Crazy Horse Memorial to see such a work being created.
9) Mesa Verde National Park, near Cortez, Colorado, and Walnut Canyon National Monument, near Flagstaff, AZ, are great examples of how people can eake out a living and build a city where you wouldn't think anybody could survive.

Of course, just look at The National Parks Service website for all sorts of cool places to go.

National Radio Astronomy Observatory in Greenbank, WV. I make a pilgrimage every year or so. I generally just do the self guided tour (ab't 2 miles).