the Great Daylight Comet of 1910, which surpassed Halley in brilliance and was actually visible in broad daylight for a short period, approximately four months before Halley made its appearance. 1986 The 1986 apparition of Halley's Comet was the least favourable on record. In February 1986, the comet and the Earth were on opposite sides of the Sun, creating the worst possible viewing circumstances for Earth observers during the previous 2,000 years. Halley's closest approach was 0.42 au. Additionally, increased light pollution from urbanization caused many people to fail in attempts to see the comet. With the help of binoculars, observation from areas outside cities was more successful. Further, the comet appeared brightest when it was almost invisible from the northern hemisphere in March and April 1986, with best opportunities occurring when the comet could be sighted close to the horizon at dawn and dusk, if not obscured by clouds. The approach of the comet was first detected by astronomers David C. Jewitt and G. Edward Danielson on 16 October 1982 using the 5.1 m Hale telescope at Mount Palomar and a CCD camera. The first visual observance of the comet on its 1986 return was by an amateur astronomer, Stephen James O'Meara, on 24 January 1985. O'Meara used a home-built telescope on top of Mauna Kea to detect the magnitude 19.6 comet. The first to observe Halley's Comet with the naked eye during its 1986 apparition were Stephen Edberg (then serving as the coordinator for amateur observations at the NASA Jet Propulsion Laboratory) and Charles Morris on 8 November 1985. Although the comet's retrograde orbit and high inclination made it difficult to send a space probe to it, the 1986 apparition gave scientists the opportunity to study the comet closely and several probes were launched to do so. The Soviet Vega 1 probe began returning images of Halley on 4 March 1986, captured the first-ever image of its nucleus, and made its flyby on 6 March. It was followed by the Vega 2 probe, making its flyby on 9 March. On 14 March, the Giotto space probe, launched by the European Space Agency, made the closest pass of the comet's nucleus. There also were two Japanese probes, Suisei and Sakigake. Unofficially, the numerous probes became known as the Halley Armada. Based on data retrieved by the largest ultraviolet space telescope of the time, Astron, during its Halley's Comet observations