HAPPY GBT DEDICATION DAY

The GBT is the world's largest fully-steerable radio telescope. It is 485 feet tall and weighs 16 million pounds.
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Let's go on a tour, starting at the base! The GBT’s foundation is 20 feet of concrete, set on solid bedrock beneath the surface.
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All 16 million pounds of the GBT’s weight rests on four “azimuth trucks,” on each of the four corners of the telescope.
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The trucks move along the 210-foot-diameter circular track, allowing the telescope to move azimuthally, or left to right.
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If you want to climb 150 feet of stairs to the next level, be our guest. We’re taking the elevator.
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You can tell when the GBT is in “maintenance mode” because the catwalk to the receiver arm is horizontal, so workers can walk across it.
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(of course, there are times our engineers have to tip the telescope while inside it for testing purposes)
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To move the GBT altitudinally, or up and down, we use the horseshoe-shaped elevation wheel at the center of the telescope.
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The dish can dip as low as 12 feet above the ground, letting astronomers observe 85% of the whole sky.
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The GBT’s surface is made up of 2,003 individual panels, each mounted on four pistons. These adjust the shape of the dish.
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It's time for another elevator! This one moves diagonally up the receiver arm.
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The GBT can have 8 receivers in its turret at once. Just rotate the correct receiver into place, and the subreflector (the smaller, circular dish) does the rest of the work.
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The view from the top of the receiver room is pretty spectacular, as long as you’re not afraid of heights.
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There are two ways to get back down: the elevator, or the fun method

/fin