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On 12 October 2026 Mercury sits 25.2° east of the Sun in Libra, shining at about magnitude −0.1. We are honest with you: it hangs very low in the north, so you will want binoculars and a clear western horizon, and the south has the best view. Try the “find Mercury” button.
Planet watching · Mercury at greatest eastern elongation, 12 October 2026
On 12 October 2026, at about 10:06 UTC, Mercury reaches its greatest eastern elongation: 25.2° east of the Sun, in the evening sky, in the constellation Libra. It shines at about magnitude −0.1, as bright as a bright star. Sounds lovely, right? We will be honest with you, though: this one is a tricky catch.
“Greatest elongation” simply means Mercury is as far from the Sun in our sky as it gets this time round. It does not mean Mercury is closest to Earth, and it does not mean it is at its brightest. Mercury’s orbit is an oval, so its greatest elongation ranges from about 18° to 28° from one appearance to the next. This time it hovers around 25° for a few days: 25.0° on 10 October, 25.2° on 12 October, 25.1° on 14 October, then 23.5° on 20 October and only 14° on 29 October.
In autumn evenings the path of the planets (the ecliptic) meets the western horizon at a shallow angle. So even with a wide gap from the Sun, Mercury stays low. Thirty minutes after sunset on 12 October it is only about 0.7° above the horizon in Vienna and about 2.8° in Istanbul. From the southern hemisphere it is a very different story: about 17.6° high from São Paulo and about 18° from Sydney.
In Vienna the Sun sets at 18:11 CEST and Mercury follows about 35 minutes later, around 18:46. In Istanbul the Sun sets at 18:28 and Mercury sets at about 19:16, 48 minutes later. So from Vienna’s latitude and further north it is very hard. In Istanbul, Greece, southern Spain, the south coast of Turkey, or anywhere south with a flat, clear west-south-west horizon, you have a real chance with binoculars.
Watch Mercury race around the Sun on its oval orbit. The big number is the live angle between the Sun and Mercury as seen from Earth, and the badge lights up at the peak. It is a schematic, not to scale.
Start looking about 20 to 30 minutes after sunset, when the sky is dark enough but Mercury has not yet slipped away. Face west-south-west: the direction is about 241° in Vienna and Istanbul, and about 256° to 259° in São Paulo and Sydney. You need a flat horizon, like a sea view, an open field or a high rooftop with nothing in the way.
Mercury stays close to 25° from the Sun for several evenings, so if 12 October is cloudy, the nights just before and after are nearly as good.
A little, yes. The new Moon is on 10 October at 15:50 UTC, so on 12 October the Moon is a hair-thin crescent, about 1.8 days old and about 4% lit. Thirty minutes after sunset, seen from Istanbul, it sits about 2.4° from Mercury. On 11 October it is 13° away, and on 13 October 10° away.
Be realistic, though: such a thin crescent is faint too. It helps most in the south, with binoculars and a clear horizon.
Wait until the Sun has fully set before you scan the horizon with binoculars, and never sweep near the Sun. Move slowly and look for a steady, bright point, about as bright as a bright star. Mercury does not twinkle much, but low air can make it shimmer.
Through a telescope, Mercury at greatest elongation looks half lit, like a tiny half Moon. Low in the sky it will wobble, but the little half-disk is a lovely reward.
“Find with camera” opens Astrometrik’s sky view: hold your phone up and an arrow points you to Mercury (or the Moon). “Where is it now?” uses your location to tell you the direction and height. Mercury is low, so look for a clear western horizon.
Mercury reaches greatest eastern elongation on 12 October 2026 at about 10:06 UTC, when it is 25.2° east of the Sun. It stays near that angle for a few days, from about 10 to 14 October.
From the northern hemisphere it is a hard target. Thirty minutes after sunset Mercury is only about 0.7° high in Vienna and 2.8° in Istanbul, so you need binoculars and a flat, clear west-south-west horizon. From the southern hemisphere it is much better, around 18° high.
Greatest elongation is the moment Mercury is farthest from the Sun in our sky. It does not mean Mercury is closest to Earth or at its brightest. It only tells you when Mercury is easiest to separate from the Sun’s glare.
Look west-south-west about 20 to 30 minutes after sunset, near the horizon. The thin crescent Moon sits close to Mercury on 12 October, which can help you if you are in the south.
Mercury shines at about magnitude −0.1, as bright as a bright star. It is hard to see only because it is so low in the bright twilight sky.
In autumn the ecliptic meets the western evening horizon at a shallow angle, so Mercury sets only about 35 minutes after the Sun in Vienna. In the southern hemisphere the same angle is steep, which puts Mercury much higher.
Date, angle and brightness come from the In-The-Sky.org elongation page and were checked against EarthSky and Star Walk style viewing guides. Altitudes and times were recalculated with Astronomy Engine.
Positions and times were recalculated with Astronomy Engine, the sky-calculation library Astrometrik uses; times for Vienna and Istanbul are local time. The artwork on this page was drawn by Astrometrik.