Free Form Post #3: The Very Large Telescope

In the first few weeks of class, we were given the assignment of defining some astronomy vocab words related to the celestial sphere. At the end of the worksheet, we were also asked to look up the coordinates of some telescopes. At the time I had no idea why we were looking up coordinates and nothing else about these telescopes. I now understand that it was an exercise in determining observability of certain celestial objects from different points of latitude on the Earth's surface. However, all I could think of was how great it was that there was a telescope named the Very Large Telescope, or VLT for short. The VLT is located high in the Atacama desert in Chile at an altitude of 2,635 meters. Here's a few images to show how far away it is from light pollution sources:

It's about a 3 hour drive from the nearest settlement and about a day's drive from the Chilean capital of Santiago. It's situated in the perfect place for a large telescope to observe the Universe. However, just how big is the Very Large Telescope? According the European Southern Observatory, which operates the telescope, the VLT is actually comprised of 4 different telescopes with primary mirrors each with a diameter of 8.2 m which can be combined to achieve a very high angular resolution. There are also four auxiliary telescopes, each with a mirror diameter of 1.8 m. Using just one of these telescopes for a 1 hour exposure period, it is possible to observe objects four thousand times fainter than those that can be observed with the human eye. While an 8.2 m telescope might not seem too big, each mirror, which is only 17.5 cm thick, has a weight of 23 metric tonnes! That's a pretty heavy mirror!

The VLT has been extremely important in recent astronomical research and has averaged one peer reviewed scientific article per day. It's description and goals, as stated on the ESO's website, is to be a general purpose large aperture optical/infrared telescope observing  high redshift galaxies, star formation, exoplanets and protoplanetary systems.

We should take a field trip!

Sources: http://www.eso.org/public/teles-instr/vlt/