Mercury at superior conjunction 2026: All you need to know

Mercury will reach superior solar conjunction—when it passes almost directly behind the sun from Earth’s perspective—on January 21, 2026, marking its transition from the morning sky to the evening sky.

Mercury at superior conjunction 2026

When it occurs: Mercury will reach superior solar conjunction on January 21, 2026, at 16:00 UTC (11 a.m. EST).

Alignment: As Mercury aligns behind the sun from Earth’s perspective at superior solar conjunction, it appears very close to the sun in our sky. As a result, it rises and sets almost with the sun.

Significance: Mercury at superior solar conjunction marks its transition from the eastern morning sky to the western evening sky.

Visibility: Around its superior solar conjunction, Mercury will not be visible in our sky for several days, as it is lost in the sun’s glare. It will reappear in the western evening sky in early February 2026 (for Northern Hemisphere observers).

However, Southern Hemisphere observers will have to wait until mid-February 2026 to see Mercury in the western evening sky. This is because, for the Southern Hemisphere, the ecliptic—the path of the sun, moon and planets—makes a narrow angle to the horizon on summer evenings.

Thereafter, Mercury will remain visible in the evening sky until late February 2026, before it begins to disappear into the sun’s glare in early March 2026. Mercury will reach inferior solar conjunction—when it passes between the sun and Earth—on March 7, 2026.

Phase of Mercury: As Mercury is on the far side of the sun from Earth at its superior solar conjunction, the side of Mercury that faces us is fully illuminated. Therefore, Mercury will be in its full phase at superior solar conjunction on January 21, 2026.

Distance from Earth: Mercury will reach its farthest distance from Earth around superior solar conjunction on January 21, 2026, passing to a distance of about 1.42 AU or 212 million km.

Size of Mercury: Mercury will appear smallest in size around superior solar conjunction on January 21, 2026. If it could be observed using proper sun-blocking filters, Mercury would measure only about 4.7 arcseconds in diameter.

How often does Mercury reach superior conjunction?

Mercury reaches its superior solar conjunction once every 116 days. This interval is called the synodic period of Mercury. It is the time Mercury takes to orbit the sun relative to Earth. The synodic period is longer than the actual orbital period of Mercury (about 88 days) because Earth is also moving in its orbit around the sun.

Upcoming superior conjunctions of Mercury

Here are the dates of upcoming superior conjunctions of Mercury:

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