John Gatenby Bolton FAA FRS CBE[1] (5 June 1922 – 6 July 1993) was a British-Australian astronomer who was fundamental to the development of radio astronomy.

While suffering from various sicknesses in his youth, such as severe asthma and migraines, Bolton showed an early interest and proficiency in sports, mathematics, and science.

[6] Bolton was awarded a place to study pure mathematics and natural philosophy at Trinity College, Cambridge in 1940, and two scholarships to cover his fees and living expenses.

While an average result for a student that had previously finished in top third of his cohort, his mother had deteriorated and died during Bolton's examination period.

At the Telecommunications Research Establishment, Bolton first worked on developing a new airborne radar system operating at a wavelength of 3 cm, which included extensive testing during flights.

[14] Bolton's experience on Unicorn is credited with developing his hands-on expertise with electronics [15] and the ideas that would help him later to build a sea-cliff interferometer.

The choice to make Australia his new home was largely due to the positive influence the climate had on his health but also because his application to enrol in postgraduate studies at the Cavendish Laboratory at Cambridge University had been rejected.

[16] His abbreviated wartime undergraduate degree was deemed inadequate training for postgraduate study by the head of the Cavendish Laboratory, Lawrence Bragg.

Through one government official associated with finding work for veterans, an appointment was made for Bolton to meet Taffy Bowen, the head of Radiophysics Laboratory of CSIR.

[19] Bolton was first assigned to measure the polarisation properties of sunspot radiations, an area of active investigation as the Sun was recently confirmed to be radio bright during World War 2.

[32] Following the Cygnus result, Bolton, Stanley, and Slee set about systematically surveying the sky with an improved sea-cliff interferometer for other discrete radio sources.

With 10 arcminute precision and a better handle on systematic uncertainties due to ionospheric refraction, Bolton could now reasonably suggest optical counterparts.

[48] On the basis of his recent academic success, Bolton did a tour of the key astronomy and radio engineering labs of the Northern Hemisphere in 1950.

Using this instrument in 1953, Bolton and new CSIRO recruit Dick McGee surveyed the Galactic Plane, identifying the centre of the Milky Way - Sagittarius A.

[54] While Bolton insisted on building a larger dish modeled on his Dover Heights prototype, the laboratory favoured the Mills Cross radio interferometer.

This decision led Bolton to direct conflict with his immediate boss Pawsey, after which he was reassigned by Bowen to the Cloud Physics division of Radio Astrophysics.

During Bolton's detour away from radio astronomy, he worked on understanding how to seed rainfall using silver iodide smoke [55] jettisoned from aircraft.

However, Bolton was aware during his brief stint in Cloud physics of the potential opportunity to start the radio astronomy group being established in California.

Along with Gordon Stanley, Bolton identified Owens Valley as an ideal site for a radio observatory because its natural mountain ranges shielded interference from coastal Californian cities and since it was reasonably close to Caltech.

[61] One of the first scientific contributions from the Owens Valley telescopes was confirmation of radio emission from Jupiter,[62] which gained significant media and institutional recognition for the instrument.

[66] Along with poor health caused by the low air quality in Pasadena smog, Bolton and his family decided to return to Australia in 1960.

Bolton had already played an important role in helping assess the design of the telescope,[67] and now took ownership of construction and commission of the Parkes dish.

NASA suggested to CSIRO for Parkes to join the Deep Space Network and be in directly involved with the Jet Propulsion Laboratory (JPL).

Bolton was keen to join this effort as he thought Parkes had a debt to NASA and the US for their help in construction and the numerous personal relationships he had developed there.

[75] Due to changes in the moonwalk schedule, NASA received TV signals from three sources - Goldstone, Honeysuckle Creek, and Parkes.