Active EVE experiments, radar detection techniques, signal processing methods, and the history of Earth–Venus–Earth radio science.
The extraordinary story of radar echoes from Venus — from planetary science to the limits of amateur radio achievement.
MIT Lincoln Laboratory transmitted an 8-second pulse at 440 MHz and, after careful analysis, claimed detection of a reflected echo from Venus on February 10–11, 1958. The result was controversial — later verification was mixed — but it launched the space-age race to radar Venus and measure its distance precisely.
The Jet Propulsion Laboratory's Goldstone tracking station achieved unambiguous Venus radar detections using an 85-foot dish and 13 kW transmitter at 2388 MHz. These measurements refined the value of the Astronomical Unit to better than 1 part in 10,000 — a landmark result for celestial mechanics.
The Arecibo Observatory in Puerto Rico, completed in 1963 with its 305-metre dish, became the world's premier planetary radar facility. Routine Venus observations revealed the planet's retrograde rotation period of 243 days — impossible to determine from optical observations through its permanent cloud cover.
Arecibo and Goldstone developed systematic Venus mapping programs. Radar altimetry revealed volcanoes, rift valleys, and highland regions beneath Venus's clouds — later confirmed by the Magellan spacecraft. The Venera landers (Soviet) and Pioneer Venus (NASA) combined orbital radar with surface data.
The Bochum Observatory (BITZ, operated by AMSAT-DL) in Germany conducted one of the most significant early amateur-scale EVE experiments using their 20-metre parabolic dish. Transmitting at 2.4 GHz during a Venus inferior conjunction window, the team achieved coherent detection of Venus radar echoes through careful pulse integration and Doppler compensation — inspiring subsequent civilian EVE efforts worldwide.
A European team attempted reception of Venus radar echoes using the EISCAT Svalbard radar transmitter (430 MHz, ~1 MW EIRP) as source and distributed amateur-grade SDR receivers across Europe. Echoes were detected in averaged data — the first claimed amateur-scale EVE reception using a network approach.
The CAMRAS team at the historic 25-metre Dwingeloo Radio Telescope in the Netherlands conducted a new EVE experiment near Venus inferior conjunction. Combining professional-heritage infrastructure with modern SDR back-ends and open-source signal processing, the team successfully integrated radar echoes over multiple sessions — one of the most capable civilian EVE attempts to date.
Modern amateur EVE efforts combine high-power transmitting sites, coherent averaging of thousands of pulses, SDRs, and coordinated multi-station reception. Digital signal processing and platforms like WSJT-X have radically lowered the technical floor, with dedicated EVE teams around the world pushing the frontier of what civilian radio science can achieve.
One of the most challenging RF propagation experiments possible. Venus as a passive radar target requires precise timing, massive power, and exceptional receiving sensitivity.
Plan your Earth–Venus–Earth experiment with this full in-browser link budget calculator — no installation required.