Mercury at greatest eastern elongation 2026: All you need to know

Mercury at greatest eastern elongation in February 2026

When it occurs: Mercury will reach its greatest eastern elongation on February 19, 2026, at 18:00 UTC (1:00 p.m. EST). At that time, Mercury will be 18.1° east of the sun, making this the best time to observe the planet in the western sky after sunset.

When to see: From early to late February, as seen from mid-northern latitudes, you will find Mercury low above the western horizon about 45 minutes after sunset. In late February, it will appear to the lower right of Saturn and above the bright Venus. This will be the best evening apparition of Mercury for the Northern Hemisphere in 2026.

After its greatest eastern elongation on February 19, Mercury will sink lower in the western sky after sunset each day. It will fade into the sunset glare in early March as it moves toward its inferior conjunction—when it passes between the sun and Earth—on March 7, 2026.

Brightness of Mercury: After emerging from the sunset glare in early February, Mercury’s brightness will rapidly decrease until it reaches inferior conjunction (its new phase) on March 7, 2026, when the illuminated side of the planet—the day side—turns completely away from us.

At its greatest eastern elongation, Mercury will shine with a magnitude of -0.4 and appear brighter than Saturn.

Visibility through a telescope: Mercury will appear 49% illuminated (nearly in its third quarter phase) and 7.2 arcseconds in diameter at its greatest eastern elongation.

Thereafter, Mercury will appear as a thinner but larger crescent each day until it reaches inferior conjunction.

View from the Southern Hemisphere: As seen from mid-southern latitudes, Mercury will emerge from the sunset glare around mid-February and be visible only for a few days around its greatest eastern elongation on February 19. For this evening apparition, Mercury will be very difficult to observe as the ecliptic—the path of the sun, moon and planets–makes a narrow angle with the horizon.

What does “Mercury at greatest eastern elongation” mean?

Mercury always appears very close to the sun in our sky because it is the innermost planet in our solar system. As it orbits the sun, it appears to move east and west of the sun in our sky.

Mercury is said to be at eastern elongation when it appears east of the sun in our sky. Here, elongation refers to its angular distance from the sun.

Mercury reaches its greatest eastern elongation when it appears at its maximum angular distance east of the sun in our sky.

Eastern elongation = evening visibility

As Mercury appears east of the sun in our sky during eastern elongation, it sets after sunset.

When Mercury appears farthest east of the sun during its greatest eastern elongation, it sets as late as possible after sunset. Around that time, Mercury emerges from the sunset glare and becomes visible in the evening twilight.

A comparison of elongations

Mercury’s greatest elongations are not equal. Its greatest elongations vary from 18° (minimum) to 28° (maximum) in our sky. For example, Mercury reaches 18.1° east of the sun at its greatest eastern elongation on February 19, 2026.

Also, Mercury’s elongations can be more or less favorable depending on the time of year they occur. In either hemisphere, Mercury’s evening apparitions (eastern elongation) in spring and morning apparitions (western elongation) 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’s greatest eastern elongations in 2026

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

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