https://www.scientificamerican.com/article/hurricane-irma-closes-arecibo-observatory/ >The second-largest radio telescope in the world has suspended operations as powerful Hurricane Irma churns ever closer. >The Arecibo Observatory in Puerto Rico, which features a 1,000-foot-wide (305 meters) radio dish, is closed for safety reasons until further notice, telescope representatives said via Twitter on Tuesday (Sept. 5).