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Earth's Radio Telescopes Combining Forces
Slatterz writes "I own a basic 70mm telescope, which I'm sure Galileo would have given his right arm for in 1609. In fact, this year marks exactly 400 years since Galileo first pointed a telescope at the skies — discovering the moons of Jupiter and helping to prove that the universe doesn't revolve around us. As a mark of respect, the United Nations has declared 2009 the International Year of Astronomy. Official festivities kick off this week in Paris and, to help start the celebrations, 17 radio telescopes in Australia, Asia, Europe and the Americas will track three quasars using something called "real-time Very Long Baseline Interferometry" — basically creating hi-res images by combining their data to simulate a telescope as large as the Earth. Sounds cool."
the United Nations has declared 2009 the International Year of Astronomy. Official festivities kick off this week in Paris and, to help start the celebrations ... a giant light display and a firework!
Galileo Galileo figaro!
Since the 1970s telescopes from all over the world (and even in Earth orbit) have been combined to perform Very Long Baseline Interferometry. Data received at each antenna is paired with timing information, usually from a local atomic clock, and then stored for later analysis on magnetic tape or hard disk. At that later time, the data is correlated with data from other antennas similarly recorded, to produce the resulting image. Using this method it is possible to synthesise an antenna that is effectively the size of the Earth. The large distances between the telescopes enable very high angular resolutions to be achieved, much greater in fact than in any other field of astronomy. At the highest frequencies, synthesised beams less than 1 milliarcsecond are possible.
Any life is made up of a single moment, the moment in which a man finds out, once and for all, who he is.
This is called eVLBI, and it is now done routinely to, e.g., determine the Earth's rotation (UT1).
From a networking standpoint, one interesting thing is that eVLBI requires high bandwidth (1 Gbps is typical), but can tolerate fairly high loss rates (because the actual cross correlation coefficients are rarely as high as 10^-3). This makes it an excellent candidate for an Internet scavenger service, where packets are sent at "less than best effort," i.e., with the understanding that they can be dropped if there is any congestion at all, so that eVLBI can use all available bandwidth without choking out other uses. The same technology may prove to be very useful for P2P services.
And hopefully they don't screw up the metric/imperial/coordinate whatever units are used across the world and its back and point in the right direction. You wouldn't want to upset Galileo on this date...
Dont get a crappy scope. it will simply discourage you.
go to orion at http://www.telescope.com/control/main/ and buy a 8" dobsonian.
you will see things that the guys that have the cheap crap cant.
you will also have a crapload more light gathering than any small lens telescope can hope to have, giving you better star views and even seeing color very well.
http://www.telescope.com/control/product/~category_id=dobsonians/~pcategory=telescopes/~product_id=08943 is a PERECT beginners telescope. it works fantastic and does not have the crapload of problems and poor viewing that anythign smaller would have.
Also if it can be bought from walmart or radio shack or even elder beerman, it's crap. do not buy it.
I have one of those and the 12" big brother to it. the 8" I loan out all the time to people interested in astronomy and they freak out when they look at saturn and see the rings seperated from the planet unlike a lesser scope can do.
the only drawback is a 8" scope can BLIND YOU if you observe the moon without filters.
Do not look at laser with remaining good eye.
For more information, the website for all of the events in the International Year of Astronomy is here. It really is amazing what you can see when you get away from light pollution.
Government - If you think the problems we create are bad, you should see our solutions!
Have some respect and call him Galilei. Do people say "Albert's theory of relativity"?
My contribution to the IYA2009 is two fold.
First, I'll be speaking at least twice this year on astronomy to the public. Once at my local library, next week actually on the Winter Constellation, and then again this summer at the local Audubon Society on Binocular Astronomy. Places like these are hungry for smart people like us to talk to the public about our passion.
The second is that I've vowed to get out and do more public observing. This is where you setup your telescope in a busy place, like in a square downtown, and exhort the public to "Come see the Moon!" You can read about one of my adventures last year at http://notthepainter.com/2008/07/come-see-the-moon/ . You can even do outreach to your friends, I've auctioned off star parties at a charity auction, and I brought my telescope to Thanksgiving dinner!
The point is, this is the year that you, the astronomer, should try and make a difference. (Oh, and for those who think you need to be super experienced to do it, you don't, I've been doing this almost 2 years now, hmm, maybe 3, I've been having so much fun I forget.)
It's a good exercise in a co-ordination of this level.
Dedicated Cthulhu Cultist since 4523 BC.
Considering he gave up his sight to use the dinky little thing he owned, the fact that he'd only give up his right arm doesn't say much about your telescope.
The radio telescopes are being 'combined' by implementing a network and analysis software running under Ninnle Linux, of course. It's really the only choice they could have made.
Wait... the Universe doesn't revolve around us? Since when? Lord, am I the victim of public education or what. And this Galileo is a MAN?
By combining you cant get higher magnification because you wont increase amount of photons hitting the sensor.
Compared to an larger reflector which puts more photons and therefor enable us to increase the magnification.
But maybe sensitivity isn't the bottleneck but the clarity, ie better resolution which also is important when zooming in.
Why would anyone find a family name more respectful than a personal name? If your name is Joe Brown, and people start referring to your work as done by "one of the browns", it's hardly a personal boost.
Anyway, when people mispronounce your surname, it's definitely going to be unflattering. I can see that happening a lot, with Galilei.
I RTFA and the summary states he would give his right arm. The article seems to say he would have given his left nut. I'm confused here.
I thought there's not supposed to be conflicting information on the internet.
Well if you have money take your telescope and get out to sea somewhere.
Yeah, and you can bring a grandfather clock to keep time. And if you're bored, you can bring along a Jenga set. Everyone loves boat Jenga.
There are some really hot alien chicks outside our galaxy who tend to leave their blinds open when they change.
Radio sensors record the full waveform so you can cross-correlate the raw signal to create a large synthetic aperture. Almost all optical telescopes just record intensity without phase, so you cannot synthesize large aperture. A few telescope sites send optical over wave guides for analog correlation. This works for optical telescopes within a few hundred meters of each other.
I thought it was mandatory for all geeks to watch Ghostbusters? Don't they know the consequences of crossing the streams?
Are they going to form Voltron?
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
While the resolution of a large array can be similar to one gigantic dish, this does not mean it is as sensitive. No matter how spread the array, it is (at best) only as sensitive as the sum of its individual elements. What is nice though is that as some sites rotate out of the array, others can be brought online, which allows for continuous monitoring of a single patch of space. Even a giant array in the desert like the VLA is not capable of performing this feat since it is still just one point as far as the planet is concerned.
Mal-2
How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
Some years ago I ran into a site to combine a large # of backyard radio telescopes into the largest VLA on the planet. I can't find it on the web any more which leads me to believe it didn't work out.
However, it is an interesting idea.
Does any one have a current link or know what happened?
putting the 'B' in LGBTQ+
http://news.bbc.co.uk/1/hi/sci/tech/7827732.stm The BBC reports on the recent findings that earlier and more accurate astronomical maps of planets and moons were created by Thomas Harriot http://en.wikipedia.org/wiki/Thomas_Harriot
So spare a thought for Thomas Harriot, and other such early pioneers, while in admiration of Galileo for this international year of astronomy. There are probably countless others who have paved the way for the love of what they do with little or no acknowledgement
But Englishman Thomas Harriot made the first drawing of the moon after looking through a telescope several months before Galileo, in July 1609. http://www.space.com/scienceastronomy/090114-first-moon-map.html
Um, ok, yeah, he discovered the moons of Jupiter. But he spent his whole life trying to figure out how they affected the tides of Earth's oceans? Apparently he decided at an early point that our Moon was too small, but couldn't he realize proximity might have something to do with it??? Even if Jupiter's moons ARE larger, I would think a mind such as Galileo's would note that gravity is quite limited by distance... ah well... I'm not perfect either...
... helping to prove that the universe doesn't revolve around us.
Ah, but it does - it is just a matter of choosing your coordinate system.