Mercury after sunset June 2026: All you need to know

Do you know that Mercury is visible for only two to three weeks at a time, either in the western sky after sunset or in the eastern sky before sunrise? The innermost planet is difficult to observe because it always appears very close to the sun in our sky.

Because of its orbital motion, Mercury appears to swing east and west of the sun in our sky. When Mercury appears farthest east of the sun in our sky—called its greatest eastern elongation—it is visible in the western sky after sunset.

June 2026 will provide a great opportunity to see Mercury in the western sky after sunset, as it will reach its greatest eastern elongation on June 15, 2026.

Mercury after sunset in June 2026

Moment of greatest elongation: Mercury will reach its greatest eastern elongation on June 15, 2026, at 20:00 UTC (4:00 p.m. EDT). At that time, Mercury will be 24.5° east of the sun.

When to see: As seen from mid-northern latitudes, in mid-June, Mercury will appear very close to the western horizon shortly after sunset, below Venus and Jupiter. It will appear much fainter than Venus and Jupiter. It emerged from the sunset glare in late May. It will be visible near the waxing crescent moon on the evening of June 16.

After its greatest eastern elongation, in late June, Mercury will move closer to the western horizon, becoming fainter and more difficult to spot. It will fade into the sunset glare in early July as it moves toward its inferior conjunction—when it passes between the sun and Earth—on July 13, 2026.

Brightness of Mercury: After emerging from the sunset glare in late May, Mercury’s brightness will rapidly decrease until it reaches inferior conjunction (its new phase) on July 13, 2026, when the illuminated side of the planet—the day side—turns completely away from us.

Mercury will shine at magnitude -1.0 in late May, magnitude +0.6 at greatest eastern elongation, and magnitude +3.0 in early July.

Visibility through a telescope: Mercury will appear 38% illuminated (nearly in its third quarter phase) and 8.2 arcseconds in diameter at its greatest eastern elongation.

Thereafter, each day, its illuminated area decreases but disk size increases until it reaches inferior conjunction (its new phase).

A comparison of elongations

Mercury’s greatest elongations are not equal. They vary from 18° (minimum) to 28° (maximum) in our sky. For example, Mercury will reach 24.5° east of the sun at its greatest eastern elongation on June 15, 2026.

Also, Mercury’s elongations can be more or less favorable depending on the time of year in which they occur. In either hemisphere, Mercury’s evening apparitions (eastern elongations) in spring and morning apparitions (western elongations) in autumn are the most favorable.

This is because, in either hemisphere, the ecliptic—the path of the sun, moon, and planets—makes a steep angle (almost perpendicular) with the horizon on spring evenings and autumn mornings.

Mercury at greatest eastern elongations in 2026

Mercury reaches its greatest eastern elongation once every 116 days, which corresponds to Mercury’s synodic period. Here are the dates of Mercury’s greatest eastern elongations in 2026:

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