The triangular platform swung violently into a rock face and sagged as it came to rest at the cliff’s base.

When it fell, the thin-skinned dome smashed through the dish and crumpled. With an enormous roar, the floating platform slipped out of the morning sun and hurtled toward the shaded jungle floor. High above the dish, an enormous 900-ton platform held the equipment needed to focus those radio waves, including a dome filled with a complex reflector system-a structure large enough to engulf a four-story house.īut as the sky brightened on that lavender morning, a crucial cable suspending the platform ruptured-and then another broke, and then another. Its mammoth, 1,000-foot-wide dish made it exquisitely sensitive, able to capture radio waves that wash over Earth with just a millionth of the energy in a falling snowflake. Now, when the sun climbs over those mountains, it shines on the tangled ruins of a scientific and cultural treasure.įor nearly six decades, the Arecibo Observatory was Earth’s largest window to the cosmos. The skies blazed in shades of lilac and dusky rose, and the rising sun cast a warm glow on a giant radio telescope nestled among the karst mountains near the island’s northern shore. On the first day of December 2020, dawn in Puerto Rico was spectacular.

Arecibo telescope history