BAA Update Obituary Harold B. Ridley, 1919-1995 Harold Bytham Ridley, who died on was almost as old as his interest in astron­ of about 200, the BAA had by 1957 pro­ February 3 this year, was born at Richmond omy and at one time he considered it as a vided ten. During his tenure of office Ridley upon Thames in the southwest of what is career. It was natural, therefore, that when maintained a correspondence with many now Greater London, on 1919 February 22. he at last had a garden of his own, he should world authorities in the meteor world in­ He was the youngest of six, three boys and start to develop his interest in astronomical cluding P. M. Millmann and I. Halliday in three girls. Some years later the family photography. Canada. He organised major observing pro­ moved to nearby Twickenham where he Meteors can be photographed with simple grammes and deduced photographic radi- attended the Orleans Boys School. On leav­ fixed cameras requiring no driven mounting ing school he took clerical jobs in the build­ or guiding and Harold built several using ing materials and site-preparation trades. Kodak Aero Ektar and Ross Xpres lenses. The United Kingdom entered World War The large photographic plates needed to Two in 1939 September and Ridley joined make full use of the wide fields were rela­ the Army in October of that year. He served tively cheap. In this photographic work he first with a Royal Artillery searchlight was greatly encouraged by Ε. Η. Collinson. battery, and soon showed his aptitude as a In 1953 he became Secretary of the Meteor lecturer and teacher, qualifying as an section and in 1954 was appointed its instructor. He was interested in the sound Director, an office he held until 1968. At this location and radar equipment which con­ time few meteor spectra had been obtained trolled the searchlights. During the long and Harold built a meteor spectrograph hours of inactivity, Harold taught himself using a 30 degree prism. On 1954 October mathematics, read a great deal and acquired 29 he was rewarded with the spectrum of a a wide vocabulary. He also studied electri­ bright Taurid, the first meteor spectrogram cal engineering during this time. All these to be obtained from this country. One of two things helped to lay a sound foundation of Perseids in 1955 showed one of the earliest practical knowledge that was to be so useful recordings of the forbidden neutral oxygen to him in later life. Later in the war, as line. The spectrum of a Perseid taken with demands for manpower changed, he was S. J. Evans in 1991 was his fifteenth and last transferred to the infantry as an instructor meteor spectrogram. He was meticulous in and spent time at Colchester Barracks. his efforts to reduce these spectra and those Photo of Harold Ridley in 1990 by Jacqueline Mitton Demobilised in 1946 February, Harold of other observers, so as to obtain the maxi­ was accepted on a teacher training course at mum information from what were often small, faint and grainy images. Eastbourne and was there from 1946 to ants for the following showers: 1955 Gemi- 1948. Taking up teaching as his chosen pro­ Ridley attended the Meteor Commis­ nids, 1956 Perseids and Geminids, 1958 fession, he taught general science subjects sion's meetings at the IAU in Dublin in Perseids and Geminids, 1959 Quadrantids, and biology at Westcliff-on-Sea, Spring 1955. At the Association's 1956 November 1960 Quadrantids and 1962 Perseids. Grove, Isleworth, Midhurst and finally at meeting he reported on the findings of the West Byfleet where he remained until retire­ Harvard Super-Schmidt programme, sup­ Meteor streams and associated comets ment, having risen to head the Science ported by work done in the Soviet Union and Harold Ridley also suggested possible Department. Czechoslavakia, that the Perseid radiant was meteor activity associated with certain Harold had been interested in astronomy fairly sharp. The Section's visual observa­ Earth-orbit-crossing comets. In the case of from an early age and made his first recorded tions over many years had shown a much comet Rudnicki 1967 II no meteors were observation, of a meteor, at the age of more diffuse radiant. He said that while it seen and the shower associated with thirteen. During his war service he talked was hard to have to accept that visual P/Grigg-Skjellerup failed to materialize in about the stars to the men in his hut and observers, himself included, had been mis­ 1972, but a significant shower now called George Mawson still remembers how led over the degree of accuracy obtained in the Pi Puppids was seen in 1977 and at Harold pointed out the constellations to him their observations, the results of the photo­ 5-yearly intervals since. He proposed the one frosty night on their long walk back to graphic work were conclusive and that link between the Phoenicids and comet camp from an evening meal in Faringdon. future radiant work should be photographic. Blanpain 1819 IV and enhanced activity of Harold Ridley was elected a member of In the light of these findings Ridley re­ the Leonids in 1965 and 1966. Meteors asso­ the Association on 1946 March 27 and defined the Section's programme of work ciated with P/Schwassmann-Wachmann 3 was elected to fellowship of the Royal which he explained at the 1957 June meet­ have yet to appear. His final prediction, Astronomical Society in 1953. ing. Briefly visual work would concentrate made in 1987 but unpublished, was for a on magnitudes and hourly rates, correlation meteor shower associated with P/Hartley 2 Meteor observations of visual and radar rates, reporting fireballs 1985 V which should be visible around 1997 Harold soon joined the Meteor Section and and new showers and telescopic meteors. November 9. took part in the visual observation pro­ Radiant, orbit and spectrographic work grammes run by the then Director J. P. M. would be photographic. These conclusions Comet observations Prentice. After his spell of teaching in were supported by Professor A. C. B. Lovell In 1960 April comet Burnham 1960 II was Westcliff-on-Sea, Harold obtained a teach­ at Jodrell Bank in a private communication. predicted to reach naked eye brightness and, ing appointment at Isleworth and, as the Some members of the Section found this as Dr R. L. Waterfield had to be away, he family home by then had been sold, he hard to accept at the time but the programme asked me if I would operate his Ascot moved into a house in Barnes with his sister Ridley set out then has stood the test of time. Observatory in his absence. Photographing Mollie. Harold's interest in photography Of the world's meteor spectrogram total a fast-moving comet with this telescope /. Br. Astron. Assoc. 105, 4, 1995 189 BAA Update them with his own instruments. This inter­ reviews, papers and articles as well as est remained his first priority for the rest of lecturing widely to the Association, local his active life. He moved to East Chinnock groups, the WEA and other societies. He near Crewkerne, Somerset in 1979. There he spoke frequently at meetings, usually with­ had what he had always wanted, a good dark out notes, and had a very clear manner of site with a low skyline (except to the north) explaining things. His talks were always in a quiet and beautiful setting. His best well illustrated, often with his own slides. driven photographs were taken during these His two Presidential Addresses were a wide- years when he used a 15cm refractor to ranging review of our current knowledge of guide a series of cameras, culminating in the 'Comets' (1977) and 'Meteorites' (1978), a Zeiss 18cm aperture f/7 lens which he used subject not previously chosen. until observing became impossible for him. Harold Ridley's contributions to the Again Harold first equipped his dark­ Journal and Section publications were far room, using this time a redundant generator too many to list in full but mention must room and building an enlarger that would be made of his valuable series of Comet give full and even illumination over a 10x13 'Prospects' in which he examined the back­ cm plate. After taking up astrometric work ground and previous performance of all on comets he borrowed a Zeiss plate known comets expected to be visible in the measuring machine from the Association so next two years ahead, giving elements of as to get the best possible results. He was a orbits, dates of visibility, expected magni­ perfectionist and spared no effort to make tudes and other data. This involved a great the best possible use of his opportunities. deal of work each year and was a valuable Harold Ridley was a photographic observer asset to the Comet Section. at heart. While he had a keen eye for plot­ ting meteor trails he did not, to my know­ Honours and service to the Association ledge, make pictorial drawings of comets or Harold Ridley was awarded the Merlin planets. He did obtain reliable magnitudes Medal in 1978 for his photographic work of comets and novae: otherwise, when not and the Walter Goodacre Medal and Gift in Outside R.L.Waterfield's observatory at Silwood guiding a photograph, he looked through the 1992 for his work on comets and meteors. Park, near Ascot in 1960. (M. J. Hendrie) telescope for the pleasure of the moment. In 1990 minor planet 4025 was named after him. really required two observers, and Harold Writing and lecturing Ridley served the Association in a num­ readily agreed to join me for a few days.