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World’s Largest Backyard Telescope

Some 35 feet tall and housing a 70 inch diameter mirror, this may be the largest amateur-built telescope on the planet today. Credit: Steve Dodds
Some 35 feet tall and housing a 70 inch diameter mirror, this may be the largest amateur-built telescope on the planet today. Credit: Steve Dodds

Ask any backyard stargazerbigger is better when it comes to telescopes. One Utah amateur has turned just such a towering dream into reality.

Truck driver by day and passionate skywatcher by night, Mike Clements has built what appears to be the world’s largest modern-day amateur telescope.  The behemoth telescope has a primary mirror measuring 70 inches (1.8 meters) across. It is housed in a black metal cage that stands some 35 feet (10.7 meters) tallthe size of a school bus.

For comparison, the most popular sizes for backyard telescopes typically range anywhere from 3 to 12 inches (7.6 to 30.5 centimeters).

At the heart of Clements’ reflecting telescope is the 900-pound (408 kilograms) mirror, one made originally for a U.S. spy satellite program. However due to some minor damage during manufacturing, the mirror was mothballed, and eventually put up for auction, which is how Clements acquired it in 2005, according to press reports .

Telescope builder Mike Clements poses in front of the massive 70 inch wide mirror at the heart of his giant reflecting telescope. Credit: Steve Dodds
Telescope builder Mike Clements poses in front of the massive 70 inch wide mirror at the heart of his giant reflecting telescope. Credit: Steve Dodds

The larger the aperture (or diameter) of the primary mirror (or lens) that collects  incoming light in a telescope, the better its image qualitywhether you view the moon, planets or distant stars. That’s why many amateur astronomers acquire what’s called “aperture fever”, always wishing for a bigger telescope.

Alongside the financial aspects, however, factors such as portability , storage and ease of use bring most stargazers down to Earth when choosing a telescope for tours of the cosmos.

Technically, the record for largest amateur-made telescope may still go to Ireland’s Lord Rosse, who in 1845 built a 72-inch-telescope that stood as the largest astronomical instrument in the world for many years.

Clements plans to eventually take his dream scope on the road, touring the country and letting the public gaze up at the cosmos up close.

I bet long lines will form for folks hoping to get a peek through this monster telescope.

 

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Comments

  1. m salganik
    November 13, 2013, 2:30 pm

    apparently it does… still needs some work but there have been very positive observing reports. Check out the forums at cloudynights.com where there have been several threads discussing this scope (with first-hand observing reports).

  2. Heriberto Villarreal
    San Antonio Texas
    November 9, 2013, 10:26 pm

    I will like to know if the telescope worked and the range