Antenna platform of the largest single dish radio telescope, Arecibo Observatory, Puerto Rico. Credit: Michael Wright

by Michael Wright

While on vacation in Puerto Rico over Memorial Day weekend, I had the opportunity to visit the Arecibo Observatory, the largest single-dish radio telescope ever constructed. The 1000-foot diameter dish was impressive, but the antenna platform grabbed my attention. Suspended on cables from 360-foot high pylons, it looked like a giant arachnid alien guarding its nest. This impression inspired my rendering of this photo that I took of the platform.

The proboscis-like object sticking below the platform is a 96-foot long, narrow-band, line feed antenna. The gregorian dome houses two reflectors that focus the radio waves into horn antennas. To get a feel for the immensity of the structure, note that there are two full-size doors between the brown stain on the dome.

The observatory is a pleasant one-hour trip from San Juan to the karst country-side near Arecibo. Also, nearby is the Rio Camuy Cave Park, which has the third largest underground river in the world. I recommend a visit if you are ever in Puerto Rico.