Halley’s comet is in an orbit around the sun, just as the Earth, Mars, Mercury, Venus etc. Halley's Comet, or 1P/Halley, is a large, high-gloss comet that orbits the Sun every 76 years. Halley's nucleus is relatively small (about 15 kilometres long, 8 kilometres wide and 8 kilometres thick).

It had its origins in the Oort Cloud and is believed to have been a long-haul comet in its early days. It is a "periodic" comet and returns to Earth's vicinity about every 75 years, making it possible for a human to see it twice in his or her lifetime. The comet's orbit was shortened considerably to a period of roughly 2,533 years, and it will next return to the inner Solar System around the year 4385.

It is the only one of its kind that can be seen from the Earth’s surface, … Officially known as 1P / Halley and popularly as Halley’s Comet, it is a large and bright comet, which orbits our Sun every 75 years or so (between 74 and 79 years), meaning it has a short period. Its coma, however, can reach lengths of 100 million km. Halley’s closest approach to Earth took place on April 10, 837, at a distance of only 0.04 astronomical units (AU; 6 million km [3.7 million miles]). By contrast, in 1996 Ulysses had zipped through the wake of comet Hyakutake in just 2.5 days. However, in April 1996 the comet passed within 0.77 AU of Jupiter, close enough for its orbit to be measurably affected by the planet's gravity.

As a periodic (or short-term comet) it has orbital period that is less than 200 years, and has therefore been observed more than once by people here on Earth over the centuries. Halley's Comet, also known as 1P/Halley, is the most well known comet in the Solar System. Halley’s Comet, also known as 1P/Halley, is the most well known comet in the Solar System. It doesn’t ‘know’ - it isn’t sentient. Only when it gets very close to the Sun does it pop over onto the northern side for a few months (reaching about 0.2 AU from the plane of the ecliptic) before it goes south again on its way back out of the inner solar system. The famous Halley's Comet is visible from Earth about every 76 years. Its mass is roughly 2.2 × 1014 kg. Halley's Comet is arguably the most famous comet. The scientist who discovered its orbit and named the comet was the English astronomer Edmund Halley in 1705. It was the large bright comet seen six months before the Norman Conquest of England in 1066 and depicted in the Bayeux Tapestry from that time. Halley's comet, for instance, at its furthest point from the Sun is about 10 AU (AU = the radius of Earth’s orbit) away from the plane of the ecliptic - on the southern side.

Though the tail of Halley’s Comet is quite large in size, compared to that its nucleus is barely 15 kilometers long, 8 kilometers wide and perhaps 8 kilometers thick. It was last seen in 1986 and won't be visible again until 2061. It is the best known short-haul kite in the Kuiper belt. Another ESA spacecraft, Giotto, had crossed the tail of Halley's comet in just a few hours.