Halley's Comet is heading back toward the inner solar system and will reach perihelion, its closest point to the Sun, on July 28, 2061.
Space Daily reported that the subsequent return will not occur until March 27, 2134, making the 2061 appearance the only realistic opportunity for many people alive today to observe the famous object.
Stargazers will not be limited to watching the sky on July 28 alone. As the comet approaches the Sun, solar heat will cause its surface to release gas and dust more actively.
This process creates a glowing atmosphere known as a coma around the icy nucleus, followed by the development of characteristic tails. Perihelion marks the spot in an elliptical orbit where a celestial body passes nearest to its host star, meaning the overall observation period will stretch over a much longer window.
Although scientists have calculated the exact date of perihelion, determining the best observation days in advance remains impossible. Viewing conditions will depend on the position of the comet relative to the Sun and Earth, observer latitude, twilight duration, weather, and moonlight.
Historical discoveries and orbital mechanics
The periodic comet takes its name from English astronomer Edmond Halley. He compared the flight paths of bright comets recorded in 1531, 1607, and 1682, concluding that they were a single object returning at regular intervals.
Halley predicted that the object would return in 1758, a forecast fulfilled when the comet reappeared sixteen years after his death. In astronomy, periodic comets are defined as those that complete an orbit around the Sun in under 200 years, establishing that comets move in predictable paths through the solar system.
According to data from NASA, recorded observations of the comet span more than two thousand years. It carries the official designation 1P/Halley, identifying it as the first catalogued periodic comet in astronomical records.
The widespread belief that the comet returns every 76 years is only an approximation. Actual intervals between appearances range from roughly 74 to 79 years because planetary gravity and minor surface emissions of gas alter its trajectory.
Viewing conditions and scientific exploration
The comet last reached perihelion on February 9, 1986. That passage proved disappointing for many observers on Earth because its alignment with the Sun created unfavorable viewing conditions across the globe.
Orbital geometry is expected to be significantly more favorable in 2061, as Earth and the comet will be positioned on the same side of the Sun near perihelion. However, brightness cannot be guaranteed because comet activity remains unpredictable, while urban light pollution could conceal a faint tail.
During the 1986 passage, the comet served as a primary target for space research. The Giotto spacecraft closed to within approximately 596 kilometres of its nucleus, revealing an elongated core that reflected very little sunlight alongside active surface areas emitting material to form its coma and tail.
Earth encounters particles from the comet every year as the planet crosses dust paths left behind during previous passages. The comet is the origin of two well-known annual meteor showers, the Orionids in October and the Eta Aquariids in May.
Astronomers maintain continuous surveillance of cosmic objects across the solar system, with instruments including the Hubble Space Telescope having previously recorded the explosion of a known comet.
