ARECIBO
| Date | Clue |
|---|---|
| 2021-11-07 | Puerto Rico's ___ Telescope, formerly the world's largest single-aperture telescope |
| 2017-06-03 | Puerto Rican home to the Western Hemisphere's largest radio telescope |
| 2011-09-15 | ___ Observatory, home of the world's largest single-aperture radio telescope |