Dish Fulfillment | Up Close

The Massachusetts Institute of Technology likes to number the buildings on its Cambridge campus, and so this radar dish sits in a first-floor corner of Building 32, a Seuss-like structure designed by famed architect Frank Gehry. But Building 32 replaced an earlier building evocatively named … Building 20.

It’s said that Building 20 was designed in a day and built as fast as possible during the thick of World War II. Because it was made of wood, it was nicknamed the “Plywood Palace.”

During the war, scientists from around the country converged on Building 20 and neighboring sites to refine the relatively new technology of radar—the acronym for “radio detection and ranging”—and build systems that could be deployed by Allied forces. They put radar onto planes, making bombing runs more accurate and providing the ability to detect German U-boats from above; developed radar for airfields to make it safer for landings in bad weather; enabled Allied planes to spot other aircraft at long distances and tell whether they were friend or foe; and built ground-based early-warning systems that could detect German V-1 rockets heading for targets in London.

Several histories of World War II and the work done at MIT make the case that while the atomic bomb may have ended the war, radar was the key technology that put the Allies in position to emerge victorious.

And it continued to impact American life in the postwar years. MIT’s radar work developed LORAN, a system that combined radar with beacons to help boaters get a more accurate fix on their position.

The radar antenna shown at left was a fortunate failure: It was not very good at tracking airplanes, but it was great at identifying rain clouds. That discovery led to the widespread use of radar for predicting the weather. Today, it’s a reminder of the past in a building full of researchers focused on what’s next: advances in robotics and artificial intelligence.

The radar dish and other ground-floor displays in MIT’s Building 32 are part of the new Innovation Trail of Greater Boston, which highlights nearly two dozen sites of scientific and technological breakthroughs. For more information, go to theinnovationtrail.org.