During the 20th century, Halley's Comet appeared in 1910 and 1986. During that most recent visit, five spacecraft from the USSR, Japan, and the European Community journeyed to Comet Halley. ESA's Giotto obtained close-up photos of the nucleus of Halley's Comet.
Although the average period of Halley's Comet's orbit is 76 years, it's not that easy to calculate the dates when it will return by simply subtracting multiples of 76 years from 1986. Gravity from other bodies in the solar system will affect its orbit. Over the centuries, Halley's orbital period has varied from 76 years to 79.3 years.
Halley's Comet will return to the inner solar system in the year 2061, with a perihelion passage in early 2062.