American and European astronomers have begun designing telescopes that will be able to see to the edge of the visible universe. Joining the Chandra x-ray, Compton gamma-ray, the soon to be launched Space Infrared observatories and the Next Generation Space Telescope, these new designs will dwarf today’s "big glass".

The European design is called OWL - OverWhelmingly Large telescope. The 100-meter diameter main mirror would gather more light and use more glass than all of the telescopes built since Galileo first saw the moons of Jupiter. Requiring as many as 2,000 highly polished segments to make up the dish-shaped mirror, OWL may cost $1 billion or more. Located in the high desert region of Chile or in the Canary Islands, it is estimated that OWL could be completed by 2015.

Why take up the engineering and economic challenges? In the last decade, the combination of the Hubble Space Telescope and ground-based observatories have combined to study previously unseen black holes, planetary systems around other stars and the birthplace of stars in glowing stellar clouds. While Hubble can see things from its place in orbit, it takes a ground-based system to gather enough light to analyze the spectrum.

With the launch of the next generation of more powerful space-based telescopes, ground-based observatories must get more powerful as well. If we are to unlock the archaeology of the cosmos, see light emitted billions of years ago, ground-based observatories must get bigger and better.

The largest ground-based telescopes at this time are the twin-domed 10-meter Keck Telescopes at Mauna Kea, Hawaii. Each telescope weighs 300 tons and the primary mirror is constructed of 36 hexagonal segments, each 1.8-meters in diameter. They cost $140 million.

The technical problems making the quantum leap from a 10-meter to a 30-meter segemented mirror loom large. Even shielded inside an 18-story steel dome, vibrations caused by the wind would blur the images. Electronics can make adjustments to correct the blur, but the precision required exceeds anything in use today. It is the difference between 1/400,000th of an inch versus 1/1,000,000th of an inch precision movements to make the telescope useful.

The other problem is money. The U.S. design is estimated to cost $700 million, "give or take $100 million," said Steve Strom, associate director of the National Optical Astronomy Observatory in Tuscon, Arizona. This dwarf’s the NOAO’s annual budget of $25 million. The National Science Foundation, the primary U.S. funding agency for big science, spent $126 million this past year on all of its major construction projects.

Mike Toner, Atlanta Journal-Constitution, 5/20/2003, pg. A1 and A12