According to one story that first appeared in a 1475 posthumous biography and was subsequently embellished and popularized by Pierre-Simon Laplace, Callixtus III excommunicated the 1456 apparition of Halley's Comet, believing it to be an ill omen for the Christian defenders of Belgrade from the besieging armies of the Ottoman Empire.

The following table sets out the astronomical designations for every apparition of Halley's Comet from 240 BCE, the earliest documented widespread sighting.

For example, " 1P / 1982 U1, 1986 III, 1982i " indicates that for the perihelion in 1986, Halley's Comet was the first period comet known ( designated 1P ) and this apparition was the first seen in " half-month " U ( the first half of November ) in 1982 ( giving 1P / 1982 U1 ); it was the third comet past perihelion in 1986 ( 1986 III ); and it was the ninth comet spotted in 1982 ( provisional designation 1982i ).

In 1456, the year of Halley's next apparition, the Ottoman Empire invaded the Balkans, culminating in the Siege of Belgrade in July of that year.

Halley's 1910 apparition is distinct from 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.

Halley's 1986 apparition was the least favorable on record.

On 8 November 1985, Stephen Edberg ( then serving as the Coordinator for Amateur Observations at NASA's Jet Propulsion Laboratory ) and Charles Morris were the first to observe Halley's comet with the naked eye in its 1986 apparition.

The next predicted perihelion of Halley's Comet is 28 July 2061, when it is expected to be better positioned for observation than during the 1985 – 1986 apparition, as it will be on the same side of the Sun as Earth.

Halley's Comet, for example, is usually very bright when it passes through the inner Solar System every seventy-six years, but during its 1986 apparition, its closest approach to Earth was almost the most distant possible.

The Halley Armada is the generally accepted and popularly used name of five space probes sent to examine Halley's Comet during its 1986 sojourn through the inner solar system, connected with apparition " 1P / 1982 U1 ".

After witnessing a bright light in the sky ( which most historians have identified as Halley's Comet, visible in Ethiopia in 1456 ), Emperor Zara Yaqob, ruler from 1434 – 1468, founded the city of Debre Berhan ( tr.

Among these was the comet of 1456 ; only named Halley's comet when Halley predicted its return in 1759.

Historian Richard Pankhurst offers the date of 1456 for the date of the founding of this church, providing a plausible argument that the light in the sky was Halley's Comet, which could have been in Shewa that year, although the traditional dates ( 10th day of the month of Maggabit, i. e. 6 or 7 March ) do not coincide with the days that the comet was most visible ( 13 through 17 June ).

Halley's star catalogue of 1678 was the first to contain telescopically determined locations of southern stars.

( It was not yet known in Halley's time that what is actually occurring includes a slowing-down of the Earth's rate of rotation: see also Ephemeris time – History.

Halley's prediction of the comet's return proved to be correct, although it was not seen until 25 December 1758, by Johann Georg Palitzsch, a German farmer and amateur astronomer.

In 2008, a trans-Neptunian object with a retrograde orbit similar to Halley's was discovered,, whose orbit takes it from just outside that of Uranus to twice the distance of Pluto.

Ground-based observations of coma brightness suggested that Halley's rotation period was about 7. 4 days.

Although only 25 % of Halley's surface was imaged in detail during the flyby missions, they revealed an extremely varied topography, with hills, mountains, ridges, depressions, and at least one crater.

This suggested only 10 % of Halley's surface was active, and that large portions of it were coated in a layer of dark dust, which retained heat.

In the 18th century, a Frenchman further embellished the story, in anger at the Church, by claiming that the Pope had " excommunicated " Halley's Comet, though this story was most likely his own invention.

Halley's closest approach was 0. 42 AU.

Halley's approach was first detected by astronomers David Jewitt and G. Edward Danielson on 16 October 1982 using the 5. 1 m Hale telescope at Mount Palomar and a CCD camera.

Halley was most recently observed in 2003 by three of the Very Large Telescopes at Paranal, Chile, when Halley's magnitude was 28. 2.

At the same time ( according to Edmond Halley's contemporary report ) Hooke agreed that " the Demonstration of the Curves generated therby " was wholly Newton's.

At the same time ( according to Edmond Halley's contemporary report ) Hooke agreed that " the Demonstration of the Curves generated therby " was wholly Newton's.

Edmond Halley's voyage in HMS Paramour for magnetic investigations in the South Atlantic met the pack ice in 52 ° S in January 1700, but that latitude ( he reached 140 mi off the north coast of South Georgia ) was his farthest south.

Although Halley's naming error was pointed out by Guillaume Le Gentil in 1756, the name continues to be used.

Giotto was a European robotic spacecraft mission from the European Space Agency, intended to fly by and study Halley's Comet.

The missions also provided data which substantially reformed and reconfigured these ideas ; for instance it is now understood that Halley's surface is largely composed of dusty, non-volatile materials, and that only a small portion of it is icy.

STS-51-L carried the Shuttle-Pointed Tool for Astronomy ( SPARTAN-203 ) satellite, also called the Halley's Comet Experiment Deployable ( HCED ).

The Roman de Rou also includes a mention of the appearance of Halley's Comet.

It also launched many probes to the Moon, Mars, Venus, and even Halley's Comet ( using the 4-stage D-1e version ).

They had a two-part mission to investigate Venus and also flyby Halley's Comet.

Comets may also transit the Sun ; for example, Halley's Comet transited on 19 May 1910.

Maher was also cast as a chief resident in a hospital on the new series Halley's Comet.

He also participated in the planning of Giotto, the European Space Agency's mission to Halley's Comet, but died before the spacecraft was launched.

* Observations of Halley's Comet would have also been made by crews on-board Space Shuttle Challenger during missions STS-51-L and STS-61-E. STS-61-E was to carry the ASTRO-1 astronomy platform in its payload bay, but was cancelled after Challenger was destroyed in a launch accident at the beginning of STS-51-L.

Giotto witnessed an appearance of Halley's Comet in 1301.

Near impacts have been depicted in Jules Verne's Off on a Comet and Tove Jansson's Comet in Moominland, while a large manned space expedition visits Halley's Comet in Sir Arthur C. Clarke's novel 2061: Odyssey Three.

This appearance may be recalled in the representation of Tigranes the Great, an Armenian king who is depicted on coins with a crown that features, according to V. G. Gurzadyan and R. Vardanyan, " a star with a curved tail may represent the passage of Halley's Comet in 87 BCE.