The 2004 panels of the Green Bank Telescope have apple-sized reflector bulbs embedded in them. Engineers can light the surface of the telescope and measure the brightnesses of each reflector to map the curvature of the dish. The shape of the GBT’s dish, a perfect parabola, must be kept for the telescope to reflect radio waves accurately into its receivers.
Retroreflector
This apple-sized reflector bulb is one of thousands embedded into the surface panels of the Green Bank Telescope. Engineers light the surface of the GBT and measure the brightnesses of each reflector to map the curvature of the dish. The shape of the dish, a perfect parabola, must be kept for the telescope to reflect radio waves accurately into its receivers.
A Thousand Points of Light
The 2004 panels of the Green Bank Telescope have apple-sized reflector bulbs embedded in them. Engineers can light the surface of the GBT and measure the brightnesses of each reflector to map the curvature of the dish. The shape of the dish, a perfect parabola, must be kept for the telescope to reflect radio waves accurately into its receivers.
100-meter Ski Slope
Tilted like this, the 100-meter dish of the Green Bank Telescope (GBT) looks like a ski slope against the light snow.
GBT Geometry
Over 13,000 steel beams support the world’s largest fully-steerable telescope in Green Bank, West Virginia. The Green Bank Telescope weighs 17 million pounds, and moves on a rotating base and a tilting gear. The triangular-armed yoke at the base supports the tilting gear. And a gigantic pyramid arm attaches behind the dish to give it strength to tower over 200 feet above the surface.
A Dish as White as Snow
The paint on the Green Bank Telescope (GBT) is a special blend that reflects sunlight, gives off heat to keep the dish from warping, and its molecules do not give off radio waves.