Cosmic Spew: July 2012

Seeing pictures of our cosmos is a beautiful thing, it sparks the imagination and pushes us to do and see more. The magical thing about astronomy is how accessible it is to anyone that has the interest. Starting out it can be very inexpensive (looking up is free), but the sky (literally) is the limit to how far you take an astronomy hobby. Where it can get expensive and seemingly inaccessible to most, is when you start talking about the world's largest telescopes. Below are the world's top five largest telescopes in order from smallest to largest.

5.Large Binocular Telescope (LBT) Aperture Size: 8.4 meters

Located on Mt. Graham in Tucson, Arizona, the LBT is a joint collaboration between the Italian astronomical community and several universities including; The University of Arizona, Arizona State University, Northern Arizona University, The Ohio State University, and The University of Notre Dame.

The telescope is unique in that it is actually two 8.4 meter mirrors on one mount. Working in tandem, the two mirrors actually have the light gathering capabilities of an 11.8 meter telescope and the resolution capabilities of a 22.8 meter scope.

Of course, at that size, images are simply astonishing...

Messier 1 - This color image of Messier 1, the Crab Nebula, was taken at the Large Binocular Telescope during November 2006 by Vincenzo Testa and collaborators from Rome Observatory.

4. Hobby-Eberly Telescope (HET) Aperture size: 9.2 meters

Built with a low cost in mind. the HET has a very unique hexagonal mirror array design. The scope has 91 identical hexagonal mirrors that measure 1 meter by 1 meter and weigh 250 pounds each. Ran by The University of Texas at Austin and located at the McDonald Observatory.

The Hobby-Eberly Telescope has started a 3 year observation called HETDEX (which stands for Hobby-Eberly Dark Energy Experiment) whose goal is to find the existence of dark energy.

A scientific revolution is underway. It will tell us more about the universe than we have ever known before, because it will tell us what makes up almost three-quarters of all the matter and energy in the universe. It will tell us if the laws of gravity are correct, and reveal new details about the Big Bang in which the universe was born.

In 2011 the HET and McDonald Observatory were threatened by the Texas wildfires, luckily it went unscathed.

3. Southern African Large Telescope (SALT) Aperture size: ~10 meters

The Southern African Large Telescope is located in, you guess it, South Africa. SALT is funded by several countries including South Africa, the United States, Germany, Poland, India, the United Kingdom and New Zealand. After some minor imaging problems, SALT was fully operational in 2010. Much like HET, SALT uses a hexagonal design with 91 hexagonal mirrors that are 1.2 meters wide making the total aperture of the telescope nearly 11 meters wide.

First light image from SALT: NGC 6530
(Lagoon Nebula 2)

2. Keck and Keck II Aperture size: 10 meters

The Keck and Keck II are twin 10 meter telescopes sitting atop of Hawaii's Mauna Kea volcano. Each scope has 36 hexagonal segments that work either as separate scopes or in tandem as one. Due to their altitude and position in the Pacific Ocean the Keck scopes are able to take some of the most clear images of any scope due to not fighting any atmospheric distortion.

A false-color composite near-infrared image of Jupiter and its moon Io, taken July 20 Hawaii time (July 21 UT) by the Keck II telescope on Mauna Kea using adaptive optics (AO) to sharpen the image.

1. Gran Telescopio CANARIAS (GTC) Aperture size: 10.4 meters

Currently the largest telescope in the world, the GTC is, to some degree, the last of it's kind. It has a total light collecting area spanning a whopping 75.7 square meters. Located in the Spanish Canary Islands and mostly funded by the Spanish government, the GTC will reign supreme as the largest telescope in the world until the revolutionary Extremely Large Telescope is functional.