SkyEye

The upper chart shows the path of Mercury across the background stars over the course of the year. Stars to magnitude +4.5 are shown with some fainter objects included to complete constellation patterns. The white circles represent the planet on the first day of the month and are scaled according to apparent magnitude. The faint paths before the first circle and after the last circle represent the planet's positions in December of last year and January of next. In general, the planet moves from right to left except when it's in retrograde and proceding in the opposite direction. As an inferior planet, Mercury never strays far from the Sun so it always begins and ends the year near the constellation of Sagittarius, located about one quarter of the way in from the left side of the chart.

The lower charts show how the appearance of Mercury changes over the year. Below each image is listed the date, the apparent magnitude, the apparent diameter of the disk (in arc-seconds), the geocentric distance (in au), the elongation from the Sun (in degrees) and the percentage of the disk which is illuminated. Like the Moon, Mercury exhibits a complete range of phases, from new to crescent to gibbous to full and back again. Because its synodic period is around four months, Mercury completes this phase cycle three times each year. Note how Mercury's magnitude varies widely, ranging (approximately) from −2.0 to +6.0 between conjunctions.

Mercury is a morning sky object at the opening of 2026 but is already heading back toward the eastern horizon, undergoing superior conjunction late in January and then reappearing in the west for the first evening apparition of the year. This evening apparition, from late January to early March, is the best time for observers in northern temperate latitudes to see the planet after sunset. Those in the southern hemisphere will need to wait until the evening apparition between late August and early November to catch their best glimpse of this tiny planet in the west. Morning apparitions of Mercury are poorer for those in the north, with the best eastern appearance taking place during the last two months of the year. The morning apparition of March to mid-May favours the southern hemisphere. The innermost planet of the solar system is occulted by the Moon once this year, in February. Although Mercury passes by all of the other planets during the year, these pairings always take place close to the Sun, often making them difficult to observe. Evening apparitions (superior conjunction to inferior conjunction) are characterised by the planet starting very bright and dimming throughout whereas morning apparitions (inferior conjunction to superior conjunction) have Mercury starting at sixth magnitude and then brightening to zero magnitude or even brighter, so the best time to seek out this elusive planet may be either side of superior conjunction.

All times and dates are in UT with the time given to the nearest hour unless otherwise indicated. Positions are geocentric apparent places and referred to the true equator and equinox of date. Diagrams showing the position of Mercury above the eastern and western horizons at sunrise and sunset for various latitudes are available here.