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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!
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.
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.
Here are some events to look at this year:
http://www.seasky.org/astronomy/astronomy_calendar_2009.html
Most can be seen with a simple pair of binoculars. Probably better off with those than with the $100 wal-mart telescope.
And back in the day, there used to be a daily email service with things to look at every night. Unfortunately, I can't find it now...
I'd rather you do it wrong, than for me to have to do it at all.
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.
Interesting.
They say:
NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
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.
Yes, this aperture synthesis is done to increase resolution, not sensitivity. In fact, all known radio sources have a finite size for VLBI (because of the inverse compton effect), and so source brightness starts to decline as baselines go towards two Earth radii. While VLBI has been done from space, if we placed a VLBI antenna on (say) Mars, there would almost certainly be no source visible on Earth-Mars baselines for any obtainable antenna size.