Mercury at inferior conjunction July 2026: All you need to know

Mercury at inferior conjunction in July 2026

When it occurs: Mercury will reach its inferior solar conjunction—when it passes between the sun and Earth—on July 13, 2026, at 01:00 UTC (9:00 p.m. EDT on July 12).

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

Visibility: Around its inferior solar conjunction on July 13, 2026, Mercury will not be visible from Earth for several days because it is lost in the sun’s glare. It will reappear in the eastern morning sky in late July 2026.

Thereafter, Mercury will remain visible in the morning sky until mid-August 2026, before it begins to disappear into the sun’s glare in late August 2026. It will be best visible in the morning sky around its greatest western (morning) elongation on August 2, 2026.

Phase of Mercury: At its inferior solar conjunction, Mercury is positioned on the same side of the sun as Earth, so the side of Mercury facing Earth is completely dark. Therefore, Mercury will be in its new phase at inferior solar conjunction on July 13, 2026.

Distance from Earth: Mercury will reach its closest distance to Earth around its inferior solar conjunction on July 13, 2026, passing within about 0.57 AU (85 million km) of Earth.

Size of Mercury: Mercury will appear largest around its inferior solar conjunction on July 13, 2026. If it could be observed using proper solar filters, Mercury would measure about 11.8 arcseconds in apparent diameter.

Transit of Mercury

A transit of Mercury is a special case of its inferior solar conjunction in which it passes directly in front of the sun, making it appear as a tiny black dot crossing the sun’s disk.

It is a rare event because it does not happen every time Mercury reaches inferior solar conjunction. Instead, it occurs only when Mercury crosses the ecliptic (the plane of Earth’s orbit) during its inferior solar conjunction.

Transits of Mercury occur, on average, about 13 times per century. The next transit of Mercury will occur on November 13, 2032.

How often does Mercury reach inferior conjunction?

Mercury reaches its inferior 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.

Mercury at inferior conjunction in 2026

Here are the dates of inferior conjunction of Mercury in 2026:

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