Mercury at superior conjunction in May 2026
When it occurs: Mercury will reach superior solar conjunction—when it passes almost directly behind the sun from Earth’s perspective—on May 14, 2026, at 14:00 UTC (10 a.m. EDT).
Significance: Mercury at superior solar conjunction marks its transition from the morning sky to the 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 late May 2026.
Thereafter, Mercury will remain visible in the evening sky until late June 2026, before it begins to disappear into the sun’s glare in early July 2026. Mercury will reach inferior solar conjunction—when it passes between the sun and Earth—on July 13, 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 May 14, 2026.
Distance from Earth: Mercury will reach its farthest distance from Earth around superior solar conjunction on May 14, 2026, passing to a distance of about 1.32 AU or 197 million km.
Size of Mercury: Mercury will appear smallest in size around superior solar conjunction on May 14, 2026. If it could be observed using proper sun-blocking filters, Mercury would measure only about 5.1 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.
Mercury at superior conjunction in 2026
Here are the dates of superior conjunction of Mercury in 2026:
| Date of superior conjunction | Distance from Earth (AU) |
|---|---|
| January 21, 2026 | 1.42 |
| May 14, 2026 | 1.32 |
| August 27, 2026 | 1.36 |
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