We all remember how James Bond in the movie Golden Eye slid down the giant dish of the Arecibo telescope in Puerto Rico, while that crazy hacker was doing some nasty tricks with his pen. If you liked that, you should probably go see the next James Bond movie, Quantum of Solace, as it has been anounced that the crew will visit the Very Large Telescope in the Atacama desert in Chile.

Go take a look at the press release if you want more details on the filming at the VLT. Back here I’ll tell you a little about the telescope and the incredible technologies it contains.

While it is called the Very Large Telescope, where the naming talent of international astronomers really shines through (see also for further proof of their original naming skills, the Overwhelmingly Large Telescope), it actually consists of four large 8.2 m in diameter telescopes, as well as four minor helper telescopes. The telescopes operate from the near ultra violet to the mid infrared on the electromagnetic spectrum, meaning that it also covers the human visible range of light. Now these 8.2 meter telescopes might seem minor compared to the Arecibo radio telescope with its 305 meters of diameter, but they are actually quite large for being optical telescopes. Now for the really amazing stuff, the four telescopes can be combined using interferometry, acting like one big whoping 200 meter optical telescope.

Building such a large interferometer is an unbelievable feat of engineering. For it to work, the telescopes has to capture the same wave of light, each shift the phase of the light exactly the right amount, and combine the waves creating constructive interference. And light waves travel, surprisingly you might add, at the speed of light! If the light paths are shifted just 1 thousands of a millimeter, the image gets blurry. This sounds like magic. Why would we ever build big telescopes if we can just put together smaller ones and get the same picture? The thing is, the picture is not the same. Using interferometry you can achieve the same resolution as one big telescope, but you will loose light. Thus the interferometer can only be used to look at relatively bright objects and you will see fringes on the image. The quality of the interferometer images are improved by filling in the “holes” in the light with the four small telescopes which can move.

Its amazing how they do it, but the magic doesn’t stop here. One of the big problems of ground based telescopes is that the Earth’s atmosphere disturbs the light before it reaches the telescope, giving rise to blurrier images. The VLT, just like many other modern telescopes, makes up for this by shooting a laser that illuminates a spot at the top of the atmosphere and measures the atmospheric disturbances of that exact instance (they can do this because they know what the laser spot SHOULD look like without any disturbance). They then bend the mirror (which is over 8 meter wide) of the telescope to correct for the disturbance just in time, and just enought for it to capture a totally sharp image, as if the atmosphere was not there. Using this technique, the VLT is able to observe objects in the near IR up to 3 times sharper than the Hubble Space Telescope. I kid you not!

So whenever you see one of the wonderful pictures of your favorite astronomical object, go think about the technologies that had to be invented, and built, for you to enjoy the beauties of our Universe. And lets hope the good Hollywood crew shows a bit of this stuff to the world.