I spent last week observing of asteroids from the telescope: our first night was just another 8-4 workday night, where we looked at space rocks in our neighborhood and out beyond Mars for eight hours.
Arriving at the control room, I sat down with my binder full of… notes on how to observe at Arecibo, which hadn’t made much sense. At any optical observatory you enter your coördinates into a computer and take an image. After verifying that you pointed the telescope correctly, you then tell the telescope system to take data for the rest of the night, occasionally adjusting pointing or focus.
At Arecibo, you’re pointed in the right direction. Alignment with the William E. Gordon Telescope is not an issue. Even with the 305-meter dish, you’re good to a few millimeters.
Getting the signal out of the receiver and properly into the computer is the hard part of observing. Instead of a few shiny silvered mirrors and a charge coupled device digitizing and sending your photons to a screen, here a maze of waveguides, cables, and wires brings signals from the matte metal dish, after being ushered into the receivers, along a path 1,600′ long to the control room. Where computer monitors would display starfields at an optical observatory, wavy lines danced across oscilloscopes at Arecibo. It felt like junior year electronics laboratory again in the physics department, so different from most of the things we were doing in astronomy, and not just because of cgs/MKS units arguments.
Ellen had considered walking me through cabling the week before our six-night-long marathon observing run, but ultimately decided that it wouldn’t make sense out of context. Wait for the actual observing run to understand the cabling.
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