Moon radar experiment (Zoltán Bay, 1946)
In 1946 a Hungarian scientist was the first person to detect radar echoes from the Moon.
History
Keywords
radar, Zoltán Lajos Bay, radar signal, antenna, radio frequency, frequency, radar station, radar echo, wave, sign, measuring instrument, reflection, distance measurement, receiver, transmitter, Moon, Earth, speed of light, mechanics, experiment, physical
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Radar station
The radar station is a 6 m x 8 m (19.7 x 26.3 ft) steel frame, fixed on a massive turntable. The radar’s angle of elevation is adjustable and the frame has 36 dipole antennas. The radar was installed on the roof of the research laboratory and the instruments were placed in two rooms on the laboratory’s 2nd floor below the radar.

- steel frame 6 x 8 m (19.7 x 26.3 ft)



- 375,000 km (233,000 mi)

Narration
The illustrious Hungarian physicist Zoltán Bay was born in the last year of the 19th century. From 1936 he carried out his scientific experiments in Budapest, both in the research laboratory at the Tungsram Trust, and at the Technical University. His main research interests focused on vacuum, gas, and light tubes, and he also conducted numerous experiments on radio technology.
It was the latter field in which he achieved outstanding results. He led a research team whose mission was to measure the distance between Earth and the Moon using radio waves. The experiments began in 1945 and were successfully completed the following year.
On February 6, 1946 the team officially announced that radar signals had been sent to the Moon and that signals reflected from the surface of the Moon had also been detected. The key to the success of Bay’s experiment was the implementation of the formula for the recurrence and summation of signals. The experiment brought about a radical change in distance measuring equipment and led to the creation of a new branch of science, radar astronomy.
The microwave signals produced by the impulse generator located in the building were transmitted, via a transmission tube, to the antenna installed on the roof. The coulometer, developed by Bay’s colleagues, made it possible to store and aggregate the signals.
1,000 signals were transmitted over a period of 50 minutes, i.e. one signal every 3 seconds. According to the measurements, the signals returned after 2.5 seconds. Thus, the researchers calculated that the distance between the Earth and the Moon is 375,000 km (233,000 mi).
The successful experiment was an answer to one of Bay’s childhood questions. I saw the Moon passing behind the tower and I asked the adults: If I climb the tower will I be able to touch the Moon?
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