Comet C/2026 A1 (MAPS) approaches perihelion.

Comet C/2026 A1 (MAPS) will reach its perihelion (the closest point on its orbit to the Sun) on Saturday 4 April 2026, when it will be approximately 0.006 AU from the Sun (i.e. 0.6% of the distance from the Sun to the planet Earth, which is about 852 700 km, or a little over twice the distance between the Earth and the Moon). At this time the comet will be 1.05 AU from the Earth, in the constellation of Pisces, but it will not be visible due to its extreme closeness to the Sun.

The orbit and position of C/2026 A1 (MAPS) and the planets of the Inner Solar System on 4 April 2026.  JPL Small Body Database.

Should the comet survive this close encounter (which is not guaranteed), then it will reach apogee (the closest point on its orbit to the Earth) two days later, on 6 April 2026. At this point it will be 0.96 AU from us (i.e. 96% of the distance between the Earth and the Sun, or 143 614 000 km), still in the constellation of Pisces and still not visible. 

Comet C/2026 A1 (MAPS) was discovered on 13 January 2026 by the 0.28 m f/2.2 Schmidt telescope at the AMACS1 Observatory at San Pedro de Atacama. The name C/2026 A1 implies that it is a comet (C/) that it was discovered in the first two weeks of 2026 (period 2026 A), and that it was the first comet discovered in this period (1). The designation (MAPS) derives from the initials of the team which discovered it, Alain Maury, Georges Attard, Daniel Parrott, and Florian Signoret.

Discovery imagery for Comet C/2026 A1 (MAPS). Alain Maury/AMACS1 Observatory.

Comet C/2026 A1 (MAPS) is calculated to have an orbital period of 1900 years and a highly eccentric orbit tilted at an angle of 149° to the plain of the Solar System, or 59° to the plain of the Solar System but orbiting in a retrograde direction, the opposite direction to the planets and the majority of smaller bodies. This orbit brings it to 0.006 AU from the Sun at closest perihelion (0.6% of the distance between the Earth and the Sun) and out to 307 AU from the Sun at aphelion (307 times as far from the Sun as the Earth or about 10 times as far from the Sun as the planet Neptune, and considerably outside the Kuiper Belt). As a comet with a period of more than 200 years, C/2026 A1 (MAPS) is considered to be a non-Periodic Comet, since it is unlikely that it would be identified as the same body on another visit to the Inner Solar System. As a comet which comes within 0.01 AU of the Sun, C/2026 A1 (MAPS) is also considered to be a Kreutz Sungrazer Comet.

The Kreutz Sungrazer Comets, a group named after the nineteenth century German astronomer Heinrich Kreutz, have been shown to share a number of other properties, notably an orbital inclination which tends to be close to 144° relative to the plain of the Solar System, and an orbit which takes them to beyond 100 AU from the Sun. In 1967 the British astronomer Brian Marsden calculated that these comets could be subdivided into two groups, which clustered around the orbits of Comet Ikeya–Seki (which visited the Inner Solar System in 1965), and the 'Great Comet' of 1882. 

From this he calculated that these comets were all remnants of a single large comet, which had first broken into two halves during a close encounter with the Sun, then smaller pieces with each subsequent pass. He further calculated that the orbit of Ikeya–Seki appeared to be very similar to that of the 'Great Comet' of 1106, which was documented by observers across Europe, North Africa, and East Asia, and suggested that this might have been the parent body for the whole family. Subsequent researchers have suggested that there are more subgroups within this family, and that the Great Comet of 1106 was itself a fragment of an earlier body, which some of the other subgroups are derived separately from.

Calculations based upon the initial observations of C/2026 A1 (MAPS) led to the conclusion that the nucleus of this comet was about 2.4 km in diameter. However, subsequent observations by the James Webb Space Telescope have led to the conclusion that it is much smaller at about 400 m in diameter. This makes it one of the smallest known comets, as well as the first Kreutz Sungrazer to have had its nucleus directly measured, giving scientists a particular interest in whether it will survive its close encounter with the Sun.

An image of C/2026 A1 (MAPS) captured by the James Webb Space Telescope on 7 February 2026. Melina Thévenot/NASA/European Space Agency/Canadian Space Agency/James Webb Space Telescope/MIRI/Qicheng Zhang/Wikimedia Commons.

See also...